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double d
11-10-2009, 07:47 PM
hey guys i am new here but love this site already . i was reading something about a company that was going to compare stock uca ,gw and dse with gstrand mod . i have a 69 camaro stripped down and cant decide how to build front end mostly because i dont know crap about suspensions. any help would be appreciated dave d

Denvervet
11-10-2009, 09:59 PM
Do a search and you'll get info ad nauseum on here. I chose the SPC adjustable arms due to their "adjustability" and look a little diff then all the other aftermarket uca's . Savitzke Classic and Custom carries them and others. You can call them and Marcus will talk your ear off explaining the entire suspension geometry issues. Great guy
http://www.scandc.com/contact.htm

ProdigyCustoms
11-11-2009, 05:24 AM
I am not a big fan of multi piece arms on true street cars. I like a solid welded arm. We sell and install DSE, Hotchkis and Speedtach arms. They are all awesome pieces and do the same thing. The Speedtech is the best deal at $500 a pair. The others are about $100 more and are great too.

https://static1.pt-content.com/images/noimg.gif

Vegas69
11-11-2009, 06:53 AM
If you go DSE they have their own gulstrand mod template.

1968Maro
11-11-2009, 08:34 AM
Let me start out by saying that I am no expert, and what I am about to write will be considered committing blasphemy on this site. However, I have been working to get smarter and make my own decisions about what the best thing to do is. I have read a bunch of the suspension forums at this site and they will help you a tremendous amount, but at the end of the day there are conflicting ideas about the best front suspension, the only way to decide is to get smart and try to make up your own mind.

The Gulstrand mod changes the pick-up points (where your UCA's attach to your front clip) which increases the "aggressiveness" of your camber curve in your front suspension geometry.

Camber curve will help to increase the tire patch that stays in contact with the ground through a curve. You can only seriously affect camber curve by changing the mounting points for the suspension on your car.

Now, that being said a couple of things to point out. I have talked with guys at Hotchkis, & DSE. They all assure me that you will gain a little bit (a half a degree or two) of camber curve by swapping your control arms because of their shape and they way they meet the spindle. It sounds to me like they are blowing smoke up my *** to sell a product, but they are also alot smarter than me. New control arms are able to affect castor signicantly because of improved shape, but not camber.

I have also heard that the other way of changing your Camber curve is with taller spindles, but I havent even tried to go down that road yet.

So long story short, I was all set to go through the headache of doing the Guildstrand mod when I talked to some guys both on this site and at lateral-g as well as some people at DSE, and they all told me the same thing. Unless you plan on auto crossing and diving into the cones at 60 miles an hour, you as a weekend cruiser will never notice a Guldstrand modification.

My car will be a cruiser, but I want it to handle and feel like a new BMW. I want that feeling of confidence that when I dive into a turn on the exit ramp that my 60’s muscle car can do it without doing a 180:drive2:. If that’s all your after then the Guldstrand modification might be a lot of work that you will never notice.

Final thought, the Guldstrand modification does improve camber, and thus improves the performance of your car. Now if you are used to racing cars, and you can leap out of a car after the qualification run wearing your nomex suit and declare that you are detecting 1 degree of wobble in your right front ball joint. Then yes you will need and want to do the Guldstrand modification.

Here are a bunch of great resources. That helped me, Pozzi, steve please feel free to shoot holes in my comments.:enguard:

http://www.pozziracing.com/first_gen_suspension.htm#Handling%20discussion (http://www.pozziracing.com/first_gen_suspension.htm#Handling%20discussion)
http://www.camaros.net/forums/showthread.php?t=151501&highlight=lower+control+arms&page=2 (http://www.camaros.net/forums/showthread.php?t=151501&highlight=lower+control+arms&page=2)
http://www.chevyhiperformance.com/tech/chassis/suspension_steering/0909chp_muscle_car_suspension_basics/stock_subframe_parts.html (http://www.chevyhiperformance.com/tech/chassis/suspension_steering/0909chp_muscle_car_suspension_basics/stock_subframe_parts.html)
http://www.chevyhiperformance.com/tech/chassis/suspension_steering/0512ch_1968_chevy_camaro_suspension_steering_upgra de/index.html
http://www.guldstrand.com/gtheory.asp

Mkelcy
11-11-2009, 09:01 AM
1968Maro - I'm not going to jump down your throat, but I think your post does yourself and this site a disservice.

This is Pro-Touring.com, not Camaros.Net. Folks who come here are looking for advice on how to make their cars handle, not what finish was on the UCA bushing retention bolt. The Guldstrand mod, tall ball joints or tall spindles - as you note - improve the camber curve for first generation F bodies. Improving the camber curve has the important effect of maintaining a larger tire contact patch when the front end is loaded in a turn. Maintaining a larger tire contact patch in turn both improves the speed you can carry through the turn and saves the tires. Take a look here at the tires on a '68 Camaro that ran at Streets of Willow, with no camber correction:

https://static1.pt-content.com/images/noimg.gif

Here's the same car from a distance:

https://static1.pt-content.com/images/noimg.gif

Now look at two cars with camber correction:
https://static1.pt-content.com/images/pt/2009/05/DSC_0599-1.jpg

and the car above without:

https://static1.pt-content.com/images/pt/2009/05/DSC_0630-1.jpg

Notice how the top of the front tires on the cars with camber correction are tucked much farther into the wheel well than on the car without camber correction? That translates into speed and safety.

I agree with your observation that control arms alone don't do much for camber correction.

Vegas69
11-11-2009, 09:08 AM
Perfect example Mike. The gulstrand mod is not alot of work. It's simply drilling new holes in your control arm mounts. I would want to trim down the existing bracket on a stock sub to make it cleaner but I'm pretty anal about that stuff.

Mkelcy
11-11-2009, 09:18 AM
Perfect example Mike. The gulstrand mod is not alot of work. It's simply drilling new holes in your control arm mounts. I would want to trim down the existing bracket on a stock sub to make it cleaner but I'm pretty anal about that stuff.

If you really want a clean look, cut off the UCA mounts, trim them as needed for the Guldstrand mounting points and reweld them to the subframe. I'd recommend building a jig first.

dhutton
11-11-2009, 09:22 AM
Great post Mike.

Thanks,
Don

Vegas69
11-11-2009, 09:23 AM
Yep..that's exactly what I was thinking. I've seen photos of exactly that. Maybe it's on Pozzi's site.

Mkelcy
11-11-2009, 09:29 AM
Yep..that's exactly what I was thinking. I've seen photos of exactly that. Maybe it's on Pozzi's site.

The DSE coilover kit comes with a jig that reflects their version of the Guldstrand mod. If you're planing on doing the cut and reweld method, you might try finding someone who's got the DSE jig left over.

double d
11-11-2009, 09:49 AM
mkelcy thats what i am talking about i stripped down the car so i could make it handle as best as possible . i want to push this car as hard as possible on the street and maybe the track knowing that i did as much as i could before assembly . i will be running a 427 sm blk 5 spd and a 9in that are currently in my 68 ss/rs . one other thing where can i find a template for the gstrand. thanks for the input guys dave d in R.I.

Twentyover
11-11-2009, 09:50 AM
A component that is not frequently comented on is the impact of body roll. Usually discussions like this revolve around negative camber gain in bump due to suspension compression in turning. Equally important is the transverse movement of the upper and lower inboard pivots as the body sets in roll. On the outboard corner, the lower inboard pivot will be pulled toward the center of the car as the body leans, and the upper inboard pivot will be pushed away from body center, resulting in +camber gain, even if there were to be no suspension compression (an impossible theoretical condition, but the concept of it reinforces the +camber gain in roll idea)

Gulstrand helps on two fronts- first, the increase angle of the upper control arm improves -camber gain in bump, and second, the distance reduction between the upper and lower pivots produces a reduced + camber gain resulting from body roll.


https://static1.pt-content.com/images/noimg.gif

This is an example of how a decent 60's street suspension works when asked to provide big grip. Stock pivot locations. Tires are 195-55/14 V700 on 6" rims, Treadwear 50. 500 lb/in springs (about 130 lb/in wheel rate) and a 7/8" front bar. I would cord the tire about 1 " in from the outboard sidewall in 3 weekends, about 125-150 miles. Inside of the tire would show MAYBE 1/2 wear. Clearly the entire tire was not getting used. but we never got a good pyro on the tire to get a temp distribution. I could have increased static negative camber, but then i would be giving up distance in braking.

To reduce the amount of positive camber the outboard tire gives, I've got a taller spindle assm (this car uses a trunion based kingpin and a swivel axle.). The taller 'spindle' assm will gain me in 2 places- I've moved the swivel up the kingpin, and stretched the kingpin 1.25" between trunions. While the car has not run w/ this configuration yet, i hope next summer to run it as a LP car at Waterford.


1968Maro, I believe you overestimate the performance of our stock '60's suspension systems with good tires, and underestimate the impact of seemingly minor tweeks. I'll point you to Sprint Cup racing, where minor adjustments of the same suspension can put a guy 1/2 sec a lap faster. Tweeks that appear on the surface to be minor can, and do, have significant impact.

No bashing, just a different perspective.

Mkelcy
11-11-2009, 10:01 AM
mkelcy thats what i am talking about i stripped down the car so i could make it handle as best as possible . i want to push this car as hard as possible on the street and maybe the track knowing that i did as much as i could before assembly . i will be running a 427 sm blk 5 spd and a 9in that are currently in my 68 ss/rs . one other thing where can i find a template for the gstrand. thanks for the input guys dave d in R.I.

Unless budget is of extreme concern, before going to the Guldstrand mod, I'd go either of two ways - the SC&C SPC arms with tall ball joints or the SC&C SPC arms with the ATS (now Speed Tech, I think) tall spindles. In the photo of the three red cars above, the car in front has the Guldstrand mod and the second car has the ATS tall spindles (we don't speak of the third "car").

I understand that the camber correction is better with either the tall ball joints or the tall spindle than with the Guldstrand mod (but I don't have either the knowledge or ability to put any of the three through a suspension analyzer), but more importantly, tall ball joints or tall spindles are both reversible and upgradeable when the next great thing comes along. Once you do the Guldstrand mod, you're pretty much stuck with it and a stock height spindle.

double d
11-11-2009, 10:03 AM
OK GREG with that said and a lot of other things i have been reading it seems to me the first thing i will do is the gstrand mod and try to figure out uca and if i should use coilovers or spring shock setup do you know if this mod will allow for a bigger rim ??? thanks dave d

double d
11-11-2009, 10:08 AM
oh boy now i am really confused money is not the issue wasting it is. i like the idea of changing something that is not permanent and if what you said is right mike will a tall spindle or ball joint allow for bigger rims ? dave d

Mkelcy
11-11-2009, 10:18 AM
oh boy now i am really confused money is not the issue wasting it is. i like the idea of changing something that is not permanent and if what you said is right mike will a tall spindle or ball joint allow for bigger rims ? dave d

For a stock subframe I'd skip the coilovers and go with the AFCO 9.5" tall springs and their spring adjuster - http://www.afabcorp.com/AFCO_Dynatech_USbrake/merchant.mvc?Screen=PROD&Store_Code=A&Product_Code=20191&Category_Code=ct_coil-access

Just cut a helix to match the subframe spring recess and you're good to go. Setting ride height isn't as "easy" as with some coil overs, but how often are you going to reset front ride height (and realign the front end)?

Both the tall spindle and the tall ball joint allow (require, in the case of the tall spindle, I'm not sure about the tall ball joint) larger front rims.

There are, by the way, a number of "tall" spindles out there. I'd avoid those with the 2" or so built in drop, they can lead to severe tie rod to wheel interference issues. The ATS tall spindle has (IIRC) 0.75" drop built in.

double d
11-11-2009, 10:30 AM
ok mike that sounds like i will be on the right track !!! you also mentioned sc&c spc arms are those just upper arms or uca and lca and is there different spring rates that i should consider if i went with the afco thanks dave d

Twentyover
11-11-2009, 10:37 AM
OK GREG with that said and a lot of other things i have been reading it seems to me the first thing i will do is the gstrand mod and try to figure out uca and if i should use coilovers or spring shock setup do you know if this mod will allow for a bigger rim ??? thanks dave d


I'm don't want to argue for Gulstarnd vs. tall ball joint vs tall spindle, I'm arguing for considering minor (in the case of tall BJ or spindle, reversable, in the case of Gulstrand CHEAP) changes to optimize the huge grip advantage from modern tires.

Agree w/ Mkelcy on coilovers, IMO the only place a coilover is required is a formula or sports racing car (this is my opinion only- others are entitled to theirs. Mine is correct, of course :) ) where quiick spring rate changes and ride height adjustments are required. Again, my opinion, coilovers have been oversold because the "race cars use them." Some do, some don't. I like the adjustable cans Mkelcy is recommending for cars that are primarily street.

I'm not aware of any mod precluding a bigger rim, although some drop spindles do mandate the use of certain offsets to clear tie rod ends

double d
11-11-2009, 10:41 AM
thanks greg ihave some time to digest all of this seeing that 8 months of winter are almost here in the northeast

Mkelcy
11-11-2009, 10:42 AM
ok mike that sounds like i will be on the right track !!! you also mentioned sc&c spc arms are those just upper arms or uca and lca and is there different spring rates that i should consider if i went with the afco thanks dave d

The SC&C lowers are pretty nice. Talk to marcus at SC&C. He's hard to get hold of, but extrememely helpful once you do.

As for spring rates, that really involves the whole car. I've got the Guldstrand mod in my '68 Camaro driver, with 650 lb./in. AFCO front springs and the Hotchkis 1.125" hollow front sway bar, with 225 lb./in. composite rear leafs and swivel bushings in the rear; no rear sway bar. The car (which is set up a lot like CarlC's car - the front car in the three red car picture above) handles very nicely, even on the track. Because the composite springs react faster than steel, they don't feel as harsh as even lower rate steel spings. I'm using Delrin style UCA/LCA bushings in stock arms, CarlC has aftermarket UCA's (and maybe also LCA's).

double d
11-11-2009, 10:52 AM
ok mike so you went with guldstrand over tall spindles why ?? and forgive me if i sound ignorant but who is carlc and how would i contact thanks dave d

Twentyover
11-11-2009, 11:03 AM
carlc is Carl Casanova, a member on this site (carlc is his username)

carlc's camaro...
http://www.geocities.com/casanoc/


One reason to go gulstrand over tall spindle is that, as good as they are, spindles are a pile of money. Not that they aren't worth it, but still, if you can get the same impact as $8-900 spindle + steering arm for a 5 cent template and a $2.00 drill bit, well, i know how my pocketbook would answer.

ProdigyCustoms
11-11-2009, 11:20 AM
You do not need tall spindles if you Gulstrand mod. There are bump steer advantages to aftermarket spindles like ATS, but the camber gain is correct by lowering the pivot point (Gulstrand Mod) on the arm instead of raising the ball joint (tall spindle).

And lets be clear, If you use a aftermarket control arm that is open in the middle, you do not have to cut off the control arm mount and re weld. You can simply drill holes lower and your finished. So the Gulstrand mod with aftermarket arms IS NOT a big labor job.

Mkelcy
11-11-2009, 11:22 AM
ok mike so you went with guldstrand over tall spindles why ?? and forgive me if i sound ignorant but who is carlc and how would i contact thanks dave d

In my case, I built my driver '68 before any of the other solutions were available.

I'm building a "budget" '67 Camaro now that will be more of a fun local mountain/track day car. For the '67 I'm using the SC&C UCA/LCA, ATS tall spindles, the AFCO spring adjusters with 550 lb/in. springs, Bilstein shocks and a Hotchkis 1.125" hollow sway bar in front; with another set of the composite springs and Bilstein shocks in the rear. The car also has solid body mount bushings, SFCs and a 3rd gen. IROC steering box.

double d
11-11-2009, 12:18 PM
thanks guys this has been very very helpful . you probably just saved me from buying an aftermarket sub frame.

dhutton
11-11-2009, 12:57 PM
The relatively high cost of the ATS spindles can be offset by the fact that they allow you to bolt on stock C5/C6 brakes and save a lot of money on brakes. It pays to select all your components including brakes before you start buying parts.

Don

Mkelcy
11-11-2009, 01:04 PM
The relatively high cost of the ATS spindles can be offset by the fact that they allow you to bolt on stock C5/C6 brakes and save a lot of money on brakes. It pays to select all your components including brakes before you start buying parts.

Don

Absolutely agree, on both counts. The ATS spindles are really well thought out pieces.

1968Maro
11-11-2009, 01:28 PM
[QUOTE=Mkelcy;597928]1968Maro - I'm not going to jump down your throat, but I think your post does yourself and this site a disservice.

This is Pro-Touring.com, not Camaros.Net. Folks who come here are looking for advice on how to make their cars handle, not what finish was on the UCA bushing retention bolt. The Guldstrand mod, tall ball joints or tall spindles - as you note - improve the camber curve for first generation F bodies. Improving the camber curve has the important effect of maintaining a larger tire contact patch when the front end is loaded in a turn. Maintaining a larger tire contact patch in turn both improves the speed you can carry through the turn and saves the tires. Take a look here at the tires on a '68 Camaro that ran at Streets of Willow, with no camber correction:


Let me start by saying this I am not an expert, hell I am not even a novice, and please take everything I say with that in mind. I am in the process of building my first car ever, and I have posted more "stupid" questions on this and other sites than anyone else. Mike you have some great examples of why Camber is important on the track and I bow to your experience and opinion, however I am still hesitant to agree with you.

There are individuals on this forum with lifetimes of experience in vehicle racing and in the production and fabrication of parts etc. I am constantly amazed by the willingness to help novices and their patience and friendliness while doing it.

I don't want to give someone bad information about their project, but I must point out that even on this thread there are conflicting idea's about the best suspension modifications. Those garage debates are part of what makes this hobby so much fun.

I have always had one very simple question about the guldstrand modification though. GM in the 60's and even today employs some of the greatest engineers in the world. The process they go through to design a car from the ground up is mind boggling. GM was developing cars for racing in the 60's they knew about camber curve and castor then just as much as they do today. So if that is the case why did they design a pony car with such pedestrian steering geometry?

The answer is this, all auto manufacturers design cars for their average consumer. The Camaro was a pony car, it’s an entry level sports car. They sold a lot more V6's then SS's, and they left a lot of things lacking in the suspension to keep costs down and make the car easy to drive for the average consumer. Most production cars even today have less negative camber in them than they should have and the reason is to give the car a little bit of understeer and make it safer for the average consumer to control.

If you go to Guldstrands site he will tell you in black in white that you can't change one thing in suspension without giving something else up. You want a greater spring rate you get a rougher ride etc.

You also do not get something for free by changing the camber curve either.

An old bit of racing humor says that an understeering car goes through the fence nose first, an oversteering car goes through the fence tail first, and with a neutral-steering car, both ends go through the fence at the same time.

It seems to me that doing the guldstrand modification is great for road and track racing, it no doubt improves the aggressiveness of the suspension. However, I have often wondered if 5+ degrees of negative camber is more aggressive than the average person is really looking for in a street machine. I know this is pro-touring and I love to watch bad penny run the cones but let’s be honest, most people who post on this site say they are looking for a bad *** street machine, that they might race every once in a while.

Some food for thought though, I have often thought that the Camaro was designed without enough negative camber (thus understeer) in order to keep the average driver from out performing their 1960’s tires. Does that negate the need for as much understeer as is currently in the car with today's modern tires?
.

Mkelcy
11-11-2009, 01:35 PM
1968Maro - Let's agree to disagree.

double d
11-11-2009, 01:47 PM
ahmen to that mike i am a novice in suspensions but i plan on learning more and becoming a better driver so i want the best handling possible dave d

Twentyover
11-11-2009, 02:26 PM
................
However, I have often wondered if 5+ degrees of negative camber is more aggressive than the average person is really looking for in a street machine. ............

Some food for thought though, I have often thought that the Camaro was designed without enough negative camber (thus understeer) in order to keep the average driver from out performing their 1960’s tires. Does that negate the need for as much understeer as is currently in the car with today's modern tires?
.


I'm not sure I've ever seen anyone advocate 5 degrees negative camber. 5 degrees caster, yes, and modern cars are in this region. I understand that Mercedes uses even higher numbers- look at their wheel turning a sharp corner.

I'm not sure I understand what you're drilling for in the second question. Cars of that era (and cars of today) have alignment specifications to maximize tire life (edit here, I initially posted wear, not life), fuel mileage, and driver comfort, in addition to handling. To compare bias tire alignment specifications and try to draw a conclusions about understeer is, IMO flawed thinking. There are more components to understeer than static alignment or dynamic camber change, and I have different expectations from a modern car than i do from my 40year old car. I anticipate that (stock) the new car would run rings around the (stock) old car, be quieter, and get better gas mileage. What I understand Pro-Touring to do is to try to elevate the performance level of old cars to modern levels. If that is not your understanding, then i guess there's a basic difference in philosophy going on.

Nor do I agree with your statement that there are inconsistencies on responders in this thread, save for you. What I believe has happened is that there has been presentations of options, and the advantages and disadvantages of those options discussed. No one option is best, because no decision takes place in a vacuum. All responders (again, save you) have argued changing the relationship between inner and outer pivots are a positive improvement.

Answering the question abot why GM designed the Camaro the way they did.... Cost. Most of these were sold w/6 cylinders and automatics. The legend of performance was based on the few, not the many. If we truly believe the engineers working with tire designs that have been out of production for 20 years know best, why are we even trying to make changes. Let's go to Coker and buy F70-14 polyglass tires that we replace every 15000 miles.

Everyone is entitled to an opinion, I choose one different then you.

double d
11-11-2009, 04:24 PM
great info here!!! and i agree that one set up does not blow away everything else but i have some great ideas presented to me here and feel less confused (kinda) than before .and this is only my second day on this site thanks to all for info .......cant wait to start tearing it up out there!!!!!! dave d

JRouche
11-11-2009, 08:06 PM
I think Twentyover pretty much described why the designers in the 60's used the alinment specs they did. And 1968Maro you are so right. The engineers back then did know all about caster and camber effect. Prolly more so than most of us. But they also had to deal with a lower technology.

Tires and shocks have come along way since then. If you were to slap on a set of the old tires and shocks that they were working with along with a GS mod or taller ball joint (tall spindles) I dont think the setup would work.

Folks that paid hard earned money for the cars, big buck, what, prolly 2500 bucks :) wound be at the dealer wondering why their new tires were chewed up.

As far as the spindle change or the modification I think unless you have a reason to change the spindle why do it. I wouldnt do it just for the taller ball joint height. It should be for other reasons and the added camber gain is just gonna be an extra plus.

I was happy to see the comment by Twentyover re: body roll and camber gain. The camber is affected by two motions. Body roll independent of suspension travel. Even though it would appear body roll causes suspension travel and that affects camber gain. Its not the case. Body roll pulling and pushing on the control arms is what affects camber gain during body roll, on top of suspension travel. I didnt get that till I did alot more reading. But, I think alot of guys have done what they can to decrease body roll and so then it becomes an issue of looking at suspension travel and camber gain.

For camber gain I think, dont know, but think 1 degree of positive camber for each inch of travel seems to be a decent goal. At .5 degrees of static camber. I dont know what the camber gain is for each of the two modifications (GSM or spindle). Has anyone ran the suspension through its motion to see what the camber gain is for each mod?? That would be some good info.

And Im a fan of looking at the caster numbers too. And thats a tricky deal. Some cars have power steering, so they can deal with alot more for a street car. A track car can deal with even more, but it will get tiring after awhile on a street car. And, 5 degrees of caster will also get you some camber gain also. But 5* for a street car without power steering will get old. It will feel like the car only wants to drive straight. Feels good at 160mph though.

This is a good thread, some great ideas. JR

double d
11-12-2009, 05:50 AM
ok so if i did go with tall spindles change uca/lca ,what is the best way to control body roll?also how would rack and pinion steering affect caster

79T/Aman
11-12-2009, 06:05 AM
the best way to control body roll is to use the correct spring and fine tune with the roll bar, one thing that is not mentioned when changing control arm point location you also change the geometry, moving the roll center affects body roll.

A rack and pinion does not affect caster settings and I would stay away from a R&P

double d
11-12-2009, 06:10 AM
forgive my ignorance ,when you say roll bar do you mean a sway bar or an actual roll bar in the car thanks dave d

Twentyover
11-12-2009, 06:56 AM
Sway bars are also known as anti-roll bars, often shortened to roll bar on this site.

I don't think I'm going too far out on a limb to surmise you are relatively new to suspension stuff. May I suggest a book such as Chassis Engineering by Herb Adams. It's not a tough read, and you'll know what questions after reading it

CarlC
11-12-2009, 07:00 AM
If you perform the G-mod (which works quite well) and think you may want to return to the stock mounting point in the future (ATS spindle) I highly suggest using an aftermarket tubular arm. Stock arms require that the upper frame mount be trimmed for clearance. Tubular arms do not need to have the mount trimmed, and hence make retro-fitting back to the stock mounting points significantly easier. When I first built mine tubular arms were nowhere to be found.

It is also good to consider options like this since it allows for room to grow in the build. Ocne you drive the car hard it's difficult to put the crack pipe down and go backwards.

That's Rocco's Mustang! Nice guy and cool car. We had a lot of fun.

1968Maro
11-12-2009, 07:16 AM
How will ATS spindles affect ride hieght?

Mkelcy
11-12-2009, 07:18 AM
ok so if i did go with tall spindles change uca/lca ,what is the best way to control body roll?also how would rack and pinion steering affect caster

Body roll? Spring stiffness and front sway bar. If you're running steel leafs in the back in any kind of reasonably hard bushings you already have a lot of rear "bar."

Rack shouldn't affect caster at all but, again, you probably don't want a retrofit rear steer rack.

Twentyover
11-12-2009, 07:22 AM
How will ATS spindles affect ride hieght?
Understand they will result in 3/4" drop w/ no other changes.

Mkelcy
11-12-2009, 07:28 AM
It is also good to consider options like this since it allows for room to grow in the build. Ocne you drive the car hard it's difficult to put the crack pipe down and go backwards.

LOL, as in you don't want to make the next step a new subframe?

CarlC
11-12-2009, 07:37 AM
Oh how I would love to, and a 3-link, but I"ll leave the cost elephant outside instead of bringing it into the room.

Though our cars are not the latest technology, they can git-er-done pretty darn well for what they are.

Mkelcy
11-12-2009, 07:49 AM
Oh how I would love to, and a 3-link, but I"ll leave the cost elephant outside instead of bringing it into the room.

Though our cars are not the latest technology, they can git-er-done pretty darn well for what they are.

Gmod, good springs and shocks, sway bar tuning, big modern tires and (in your case) 500RWHP will "git-er-done."

It was nice to be able to use the Streets of Willow pictures to a good end. I hope Chad doesn't mind.

double d
11-12-2009, 07:50 AM
i saw on your camaro page you went to speed tech arms how are those compared to sc&c thanks dave
If you perform the G-mod (which works quite well) and think you may want to return to the stock mounting point in the future (ATS spindle) I highly suggest using an aftermarket tubular arm. Stock arms require that the upper frame mount be trimmed for clearance. Tubular arms do not need to have the mount trimmed, and hence make retro-fitting back to the stock mounting points significantly easier. When I first built mine tubular arms were nowhere to be found.

It is also good to consider options like this since it allows for room to grow in the build. Ocne you drive the car hard it's difficult to put the crack pipe down and go backwards.

That's Rocco's Mustang! Nice guy and cool car. We had a lot of fun.

CarlC
11-12-2009, 08:02 AM
They are different animals, but yield similar results. There will always be some who like one type vs. another. You may want to visit their respective websites and perform a site search here for additional info.

double d
11-12-2009, 08:03 AM
ok thanks carl

CarlC
11-12-2009, 08:06 AM
I hope Chad doesn't mind.

I don't think he will mind using the pictures nearly as much as prematurely wearing out a brand new pair of shoes.

406 Q-ship
11-12-2009, 09:33 AM
I have always had one very simple question about the guldstrand modification though. GM in the 60's and even today employs some of the greatest engineers in the world. The process they go through to design a car from the ground up is mind boggling. GM was developing cars for racing in the 60's they knew about camber curve and castor then just as much as they do today. So if that is the case why did they design a pony car with such pedestrian steering geometry?

The answer is this, all auto manufacturers design cars for their average consumer. The Camaro was a pony car, it’s an entry level sports car. They sold a lot more V6's then SS's, and they left a lot of things lacking in the suspension to keep costs down and make the car easy to drive for the average consumer. Most production cars even today have less negative camber in them than they should have and the reason is to give the car a little bit of understeer and make it safer for the average consumer to control.

If you go to Guldstrands site he will tell you in black in white that you can't change one thing in suspension without giving something else up. You want a greater spring rate you get a rougher ride etc.

You also do not get something for free by changing the camber curve either.

An old bit of racing humor says that an understeering car goes through the fence nose first, an oversteering car goes through the fence tail first, and with a neutral-steering car, both ends go through the fence at the same time.

It seems to me that doing the guldstrand modification is great for road and track racing, it no doubt improves the aggressiveness of the suspension. However, I have often wondered if 5+ degrees of negative camber is more aggressive than the average person is really looking for in a street machine. I know this is pro-touring and I love to watch bad penny run the cones but let’s be honest, most people who post on this site say they are looking for a bad *** street machine, that they might race every once in a while.

Some food for thought though, I have often thought that the Camaro was designed without enough negative camber (thus understeer) in order to keep the average driver from out performing their 1960’s tires. Does that negate the need for as much understeer as is currently in the car with today's modern tires?
.

I will jump into this a bit. As a past employee of Guldstrand Sport Suspension I can tell you what Guldstrand told me back well before there were the options of UCA's and taller spindles. As a racer for Chevy back in 1960's Guldstrand's involved in the suspension development in an advisory position, he was able to gain access to geometry infomation and the envelope that the engineering staff were instructed to stay within. Guldstrand being from an engineering background (he has a degree in Electrical Engineering if memory serves) saw an area that the engineers had left room for movement on the upper control arm mounts so by dropping the hole location he could improve the camber gain on weight transfer during cornering load, also if you notice the front hole is dropped a bit more than the rear hole this is to improve the brake dive. This was the racer in Guldy trying to find every advantage to win, remember it is only cheating if you get caught (believe me there are plenty more stuff they did to the 1st gen).

GMs engineers were limited by tires (remember bias plys were the norm for the 60's), liability (yes even then), and what was felt the American buying public would accept. These restrains dictated the suspension geometry, remember this front suspension was also for the pedestrian Chevy II/ Nova as well. The street tires at the time would never take the abuse of a "set up" suspension with things like camber gain, high amounts of caster, or negative roll centers. In those haloed days the auto companies thought that understeering saved lives, the montra was "Understeer scares the driver, oversteer scares (kills) the passenger." The American buying public would have never accept a car that gave real steering wheel feedback, over boost was order of the day and another good reason to compromise geometry to scare the hell out of the driver to keep them from going beyond the limits of the tires and skills. The Camaro in comparison to the Mustang is head and shoulders above, Ford actually built positive camper gain into the Mustang. Shelby actually did alot of work to the front of the GT Mustangs to get them anywhere near his liking, Shelby never wanted to try to make the early Mustangs into racers (and he said it a few times).

68Formula
11-12-2009, 10:38 AM
...also if you notice the front hole is dropped a bit more than the rear hole this is to improve the brake dive.

My understanding is the steeper the angle, the more anti-dive is built in. So dropping the front point more would reduce anti-dive. If that is correct, then when you say "improve the brake dive", you mean the setup has too much anti-dive built in from the factory? Or does the amount of anti-dive affecting something else in a negative way?

406 Q-ship
11-12-2009, 10:50 AM
My understanding is the steeper the angle, the more anti-dive is built in. So dropping the front point more would reduce anti-dive. If that is correct, then when you say "improve the brake dive", you mean the setup has too much anti-dive built in from the factory? Or does the amount of anti-dive affecting something else in a negative way?

I don't remember if it had too much (his opinion) and lowering the front bolt hole helped with turn in under braking or not, I just remember Guldy mentioning it. I believe that your right that by lowering the front hold will reduce the amount of anti-dive in the geometry. That is a good question and maybe I should give Tricky a call and see what he says. :hmm:

nicks67camaro
11-12-2009, 11:16 AM
If you perform the G-mod (which works quite well) and think you may want to return to the stock mounting point in the future (ATS spindle)

So basically you would keep the OEM holes and have a "dual" upper a-arm mount pattern? I would like to go to the AFX spindle but don't have the cash. I sitll want all the performance I can get.

Good tread.

1968Maro
11-12-2009, 11:28 AM
406

Thanks! That is a much better explanation of what I was looking for in my question about GM engineers attempting to prevent drivers from outperforming their 1960's tires. "One last thing that I need to mention, the other reason that we are forgetting for the stock geometry set up is ease of steering with manual steering. You can't have to much Castor or the car becomes a pain to turn"

Mike, Greg

First of all a correction, I was wrong in my previous post about the numbers for the amount of Negative Camber the G-MOD is designed to give you. He tops out at 2 degree's and nobody recommends more than that.

After returning to Pozzi's site and re-reading some of his information it seems we were both right.

Guldstrands recommendations for a pro-touring car are

1/4 to 1/2 a degree of negative camber

Guldstrands recommendations for a racing car are

1.5 degree's to 2 degree's.

A stock 1 gen camaro is designed with 1/4 to 1/2 degree of positive camber.

It seems that there is an "appropriate" amount of negative camber depending upon what you plan on doing with the car.

Which now raises another question, does anyone sell a template or a jig for the pro touring g-mod? Is the one that DSE sells, or that you can get off of Guldstrands site the more aggressive of the two?

“Sound of me eating my hat”

79T/Aman
11-12-2009, 03:06 PM
Sway bars are also known as anti-roll bars, often shortened to roll bar on this site.

I don't think I'm going too far out on a limb to surmise you are relatively new to suspension stuff. May I suggest a book such as Chassis Engineering by Herb Adams. It's not a tough read, and you'll know what questions after reading it


You are right, maybe I should start with an easy read Dr.Seuss perhaps!?

Anti-roll bar is what I meant but you knew that.

406 Q-ship
11-12-2009, 03:10 PM
406

Thanks! That is a much better explanation of what I was looking for in my question about GM engineers attempting to prevent drivers from outperforming their 1960's tires. "One last thing that I need to mention, the other reason that we are forgetting for the stock geometry set up is ease of steering with manual steering. You can't have to much Castor or the car becomes a pain to turn"

Mike, Greg

First of all a correction, I was wrong in my previous post about the numbers for the amount of Negative Camber the G-MOD is designed to give you. He tops out at 2 degree's and nobody recommends more than that.

After returning to Pozzi's site and re-reading some of his information it seems we were both right.

Guldstrands recommendations for a pro-touring car are

1/4 to 1/2 a degree of negative camber

Guldstrands recommendations for a racing car are

1.5 degree's to 2 degree's.

A stock 1 gen camaro is designed with 1/4 to 1/2 degree of positive camber.

It seems that there is an "appropriate" amount of negative camber depending upon what you plan on doing with the car.

Which now raises another question, does anyone sell a template or a jig for the pro touring g-mod? Is the one that DSE sells, or that you can get off of Guldstrands site the more aggressive of the two?

“Sound of me eating my hat”

We used -1/4° to -1/2° camber for tire life and most people are just not that agressive in a street situation. Now when I did alignment at Guldstrands I would typically "read" the tires to see how agressive a drive was on a car before setting the alignment. Some people got 0° camber to keep the tires alive for a long time other need -3/4° to keep the front of the car underneath them. For a track car I would go with the Guldstrand's race numbers, I think David's number should be pretty damn close. David Possi reminds me alot of Guldstrand.

68Formula
11-12-2009, 03:46 PM
You are right, maybe I should start with an easy read Dr.Seuss perhaps!?

Anti-roll bar is what I meant but you knew that.

Having read Fox in Socks out loud about 20 times, I can assure you the Herb Adams book would be a much easier read.

TitoJones
11-12-2009, 04:21 PM
Also a good thread:

https://www.pro-touring.com/forum/showthread.php?t=18789

Tyler

79T/Aman
11-12-2009, 05:13 PM
Having read Fox in Socks out loud about 20 times, I can assure you the Herb Adams book would be a much easier read.

LOL, well I hope Mr fast was trying to be funny and not throwing a flame job at me for a typo but he realy should proof read the last sentence of his paragraph that was meant to belittle me, Oh the irony
" It's not a tough read, and you'll know what questions after reading it" :rolleyes:
I can't make out what it says

6'9"Witha69
11-12-2009, 05:16 PM
LOL, well I hope Mr fast was trying to be funny and not throwing a flame job at me for a typo but he realy should proof read the last sentence of his paragraph that was meant to belittle me, Oh the irony
" It's not a tough read, and you'll know what questions after reading it" :rolleyes:
I can't make out what it says
As I see it, it was not directed to you at all. It was directed at this guy:

forgive my ignorance ,when you say roll bar do you mean a sway bar or an actual roll bar in the car thanks dave d His post is directly under yours. The answer by Greg then makes sense

Sway bars are also known as anti-roll bars, often shortened to roll bar on this site.

I don't think I'm going too far out on a limb to surmise you are relatively new to suspension stuff. May I suggest a book such as Chassis Engineering by Herb Adams. It's not a tough read, and you'll know what questions after reading it

79T/Aman
11-12-2009, 05:34 PM
well I wrote "roll bar" as well but I do know better I'll laugh about it :) sorry don't mean to ruffle feathers

Twentyover
11-12-2009, 07:20 PM
deleted by author

double d
11-13-2009, 04:28 AM
LOL, well I hope Mr fast was trying to be funny and not throwing a flame job at me for a typo but he realy should proof read the last sentence of his paragraph that was meant to belittle me, Oh the irony
" It's not a tough read, and you'll know what questions after reading it" :rolleyes:
I can't make out what it says
i think he originally wrote that to me . like i said when i started this thread, i am pretty green about suspension .

CarlC
11-13-2009, 08:06 PM
So basically you would keep the OEM holes and have a "dual" upper a-arm mount pattern? I would like to go to the AFX spindle but don't have the cash. I sitll want all the performance I can get.

Good tread.

Yup.

A while back I did some testing with Hotchkis running slalom, braking, etc. What we found was that -1* camber and 6* caster worked quite well for my car . Part of the decision process is that, though the car is primarily a street car, I drive the car pretty hard. Hence, tire wear was working out well with -1*. If the car was a daily driver that deals with a lot of easy driving, then relaxing the camber to -1/2* might work out better.

On the track the car needs -2* or else the outside of the tire wears excessively.

In when all is said and done the only true way to determine what works best on the car is to drive it and experiment. With all of the changes that we are introducing there are far too many variables to be able to say with certainty what are the best settings.

nicks67camaro
11-14-2009, 07:10 AM
Thanks Carl.

Double D, Like Mkelcy said in an earlier post one option could be run the SC&C arms with the Tall upper ball joint / With gmod / and their tie rod ends. Then If you want to go for the AFX spindle just install the "stock" upper ball joint and return the upper a-arm to the factory location and a factory tie rod.

This is exacty what I am doing. I try to keep my car on the road as much as possible and without the unlimted budget I upgrade as I can. When the budget comes around I will go with the AFX spindle.

There are lots of options.

Mkelcy
11-14-2009, 07:32 AM
Thanks Carl.

Double D, Like Mkelcy said in an earlier post one option could be run the SC&C arms with the Tall upper ball joint / With gmod / and their tie rod ends. Then If you want to go for the AFX spindle just install the "stock" upper ball joint and return the upper a-arm to the factory location and a factory tie rod.

This is exacty what I am doing. I try to keep my car on the road as much as possible and without the unlimted budget I upgrade as I can. When the budget comes around I will go with the AFX spindle.

There are lots of options.

Nope - Gmod OR Tall ball joints OR tall spindle. You don't double up on any of the solutions as too much is too much. Also, I'm not sure I follow on the tie rod ends. So far as I know, none of the solutions require a tie rod swap.

CarlC
11-14-2009, 07:32 AM
Do not run multiple camber correction methods. Run just the G-mod, or just the tall spindle, or just the tall ball joint. If more than one correction is done then too much of a good thing happens and a jacking effect occurs. Not a good thing. Pick your single method and try it.

CarlC
11-14-2009, 07:33 AM
Good morning Mike.

Mkelcy
11-14-2009, 09:02 AM
Good morning Mike.

'Morning Carl.

nicks67camaro
11-14-2009, 09:14 AM
Nope - Gmod OR Tall ball joints OR tall spindle. You don't double up on any of the solutions as too much is too much. Also, I'm not sure I follow on the tie rod ends. So far as I know, none of the solutions require a tie rod swap.


Oh...I thought the Tall ball joint and the Gmod worked together. I meant to say the tie rod ends from SCandC that lover the pivot point to help with Bumpsteer. (helping the overall package)

Glad I was watching this tread could of made a big no no.....

double d
11-16-2009, 04:47 AM
i am going to try and get in touch with marcus from sc&c this week. i like the idea of tall spindles and sc&c uca/lca.the right springs and shocks ,maybe a lee steering box ? i am thinking this will get me close to where i want to be without changing the subframe . any comments would be appreciated. thanks ahead of time dave d in r.i.

Chad-1stGen
11-27-2009, 08:14 PM
I don't think he will mind using the pictures nearly as much as prematurely wearing out a brand new pair of shoes.

Bwahahaha

So I'm day dreaming about my car earlier today and haven't really wanted to do another track day without doing something about my suspension. I decided when I get home to do something serious about looking into a tall ball join setup and what do I'm come across in my first search looking for which is more effective between a tall ball join and g-mod but my poor car being hung up as the poster boy for the epic fail that is stock geometry suspension on a track. I laughed and maybe I did cringe a bit too :p

I'm 99% there to ordering the SC&C kit with the adjustable upper arms and tall ball joint. Now I'm trying to decide between the really tall one and the tall one and if I should go ahead and get the tall tie rods too. And of course do they work with my 16" equivalent rims.

/wave Carl and Mike

CarlC
11-27-2009, 08:26 PM
We love ya Chad!

Mkelcy
11-28-2009, 06:02 AM
Bwahahaha

So I'm day dreaming about my car earlier today and haven't really wanted to do another track day without doing something about my suspension. I decided when I get home to do something serious about looking into a tall ball join setup and what do I'm come across in my first search looking for which is more effective between a tall ball join and g-mod but my poor car being hung up as the poster boy for the epic fail that is stock geometry suspension on a track. I laughed and maybe I did cringe a bit too :p

I'm 99% there to ordering the SC&C kit with the adjustable upper arms and tall ball joint. Now I'm trying to decide between the really tall one and the tall one and if I should go ahead and get the tall tie rods too. And of course do they work with my 16" equivalent rims.

/wave Carl and Mike

Not "hung out" as the epic fail that is stock geometry suspension on a track, more like "lovingly presented" as the epic fail that is stock geometry suspension on a track. :)

Chad, I'd call Mark at SC&C about all three of the tall upper and lower ball joints, the tall tie rods (not sure what these are) and wheel fitment.

Chad-1stGen
11-28-2009, 08:59 AM
Yeah, I sent him an email with a bunch of questions. If I don't hear back after a business day or two I will try calling him.