Which rear suspension? 3 link? 4 link?

[CamaroJesse]

Ive been searching the forum for a while now trying to figure out what rear suspension is actually needed. On my 68 camaro i have dse leafs, bilsteins, and tubbed out back. It sucks. rides bad and wheel hops like crazy. So im looking into doing a link set up. But the question is which one to go with? I dont wanna spend as much as the LD 3 link cost although it would be nice.
Right now im looking into the detroit speed 4 link and the prodigy 4 link. They arent priced that high. I just dont know what to get. What are the differences? Its mainly a street car but will be road raced a few times a year and probably auto crossed alot. I just dont know what the actual difrences are between all these different set ups. Looking for something id be happy with and not break the bank.

thanks
jesse

[ProdigyCustoms]

I am not sure a 3 link can be bought? The Chris Alston G Link is exciting though. the Quadrlink is great.

A lot of it really depends on how much fab you want to do and exactly how hard your going to push the car. Whatever difference there is between a 4 link and 3 link, it is at such a extreme edge most would never find it.

3 link is the most fab, followed by the Quadralink, then the G Link is easiest weld in. I am doing a G link in my own car.

[CamaroJesse]

I was watching videos of dse's 2nd gen on the auto cross and that thing looks like it rips! But im liking the G link because i can install it in my garage and it doesnt look too hard. Is there a big differance between the two?

[JRouche]

Hmmm.. Well, a three link is what I would recommend. But some welding is gonna be needed. A 4-link is gonna need the same amount really. The points where you are connecting the links is a major factor. Are you looking to tie into the existing rails?

Is there a frame under the car or just sheet metal formed into a frame like structure, unibody??

You will have to re-enforce the frame rails if they are sheet metal. Otherwise you are looking at elongation of the mounting holes.

Im not familiar with the 1st gen or any gen Camaros. Are they a sheet metal frame?? Not a problem, just re-enforce the mounting holes. The structure is solid enough..

And are you thinking about a true 4-link or a 4-bar system. A common four link rear suspension will almost always encroach into the passenger compartment cause the forward upper brackets are so large, they need the room. And cause the way the upper bars come off the axle they are up there by about 3-4 inches. So shoot a line that high off yer axle tube forward, it looks like its into the rear seat, and it usually is.

A 4-link suspension is geared for adjustability. And to get that you need some tall brackets. Most guys dont need that much adjustability.

A 3-link will be fine, just gotta make sure its really stout for the upper link and mounts. And do some reading about the geometry for them. They are simple to a fault. There are critical points to take care of but really they have some great advantages.. I would go three link, if yer up to it. JR

Oh, here is the room a 4-link takes up. Can you stuff that up there???? LOL I put this in my car.

https://static1.pt-content.com/images/pt/2009/05/4linkclip1-1.jpg

[gvanlaar]

The G-link from chassisworks and the Quadralink from DSE take much less room than that one. Lateral Dynamics also offers a three link.

[JRouche]

The G-link from chassisworks and the Quadralink from DSE take much less room than that one. Lateral Dynamics also offers a three link.

No, I know, I was just kidding with that pic, dont think thats what Jesse wants to stuff under his car. But it will fit :) JR

[BillyShope]

If you're going to fab a 3link, Page 18 of my site includes a setup spreadsheet which provides equal rear tire loading on acceleration (as with the early C-Type Jaguar). For an autocross car, you're probably going to want something less than 100% antisquat. The spreadsheet allows you to input your desired percent antisquat. But, since all the acceleration loads would not then be carried through the links, it was necessary that I assume a roll stiffness distribution. I assumed a 60/40 (front/rear) distribution, which is probably "good enough." If you wish to change that assumption, my source code is available and, if you're familiar with HTML, you can make the necessary changes.
http://home.earthlink.net/~whshope
over 150,000 page views

[Bryce]

i am building a 3link for my car, because of the no binding, If the geometry is correct. I am going to build it my self, like i built my front suspension.

But you have to ask how much money and time do you want to spend. Also will the rest of the car be up to par with a one off rear suspension. Can your chassis and tires handle what u want ur suspension to do?

[gizmo]

The previous post poses some important questions.

From what I have been told 4 links are mainly geared toward drag racing. (So for the purposes of autocross, stay away from four links).

A 3 link (with a watts link) would be your best choice, but beware: tuning a 3 link to meet your needs is difficult, and if you're looking for optimal performance with little fab knowhow then I'd stay away from a 3 link because it'll probably end up causing more harm than good. Granted, I know very little about 3 links, but I know when they're properly designed and tuned for the occasion they're virtually unbeatable. But often they're not, especially when amateurs are making them, and I think those are the people that end up with counterproductive results.

I know nothing about a glink so no feedback there.

I haven't heard anyone recommend a truck arm setup, which is what I choose for my Chevelle. Maybe they've been overlooked because they're geared for A bodies rather than camaros, but a baby can tune a properly installed truck arm suspensions. Granted, they are probably inferior to a 3 link in many respects, but they offer a fairly easy installation (unless your car rides low or your secondary headers dump out the back in which cases you'll have to adjust the floor pan and likely reroute the headers). And they seem to do okay on the NASCAR circuit...

No matter what you do, make sure the frame is square, and that you install it precisely. Even if you get the world's best suspension with the world's greatest secrets, if you aren't square or if things got out of shape then you've done more harm than good with the upgrade.

gizmo

[BillyShope]

And they [truck arm setups] seem to do okay on the NASCAR circuit...

gizmo
Keep in mind that the rules require this setup. Who knows what they'd run if they had freedom of choice?
http://home.earthlink.net/~whshope
over 150,000 page views

[ProdigyCustoms]

The previous post poses some important questions.

From what I have been told 4 links are mainly geared toward drag racing. (So for the purposes of autocross, stay away from four links).

gizmo

I see this is your very first post so I will try not to be to hard on you. Anytime a post starts out or includes:


The previous post poses some important questions.

From what I have been told ............................

gizmo

From what I have been told ............................ Means we have the proverbial virgin teching Sex Education. Basically it says, While I have not personally had sex, I have read the books so I am qualified to speak on the subject.

When in reality, there is no substitue for personal experiance.



The previous post poses some important questions.

From what I have been told 4 links are mainly geared toward drag racing. (So for the purposes of autocross, stay away from four links).

gizmo

More incorrect words could not be spoken on this subject. There are plenty of 4 links designed for G Machines that are awesome. A DSE Quadralink, CA G Link, are right there with 3 links for all out performance.

Probably the 2 baddest autocross Camaro's on the planet are Steve Bad Penny (3 link) and DSEs 2nd gen (4 link) and while Steve's 3 link car has beat the DSE car each time they have been run against each other, it is always by milliseconds at best. And driver could cover that.

As I said, we want you to feel free to post here. Please do not be offended.

[gizmo]

First post and last post I imagine. I clearly have nothing worthwhile to contribute here.

This is exactly the kind of help that led me to buy all the wrong things for my car. The kind of help that has kept my car unfinished for seven years. The kind of help that prevented me from ever racing my car with my dad because he died before we ever could finish it.

To be honest with you, I have plenty of solid advice to offer this forum. But I'm not entirely sure it's welcome. Now I'm no expert, but I had an expert fabricator working on my car, constantly correcting mistakes I had made (and luckily offering better advice for the future) and I had hoped to impart that knowledge here on someone else so that they might not fall folly to my mistakes.

I thought I made it clear that a 3 link was superior to all, however also very difficult to master. I thought I made it clear that I had no idea what a G link was, and so I began to wonder if I could not find the answer on google then maybe I should best ask my girlfriend (no tomato's please), and as far as four links go my fabricator said he'd rather fab the monstrocity [truck arms] in then a fourlink because four links were for straight lines. Maybe he had an agenda when he said that, because he also steered me away from the fuller rollerized Jerico tranny for its lesser half (with only a rollerized tailshaft), but I trusted the guy and because of him, most of the parts I bought before him (like my negative roll front suspension) are sitting ina box awaiting a superior replacement.

But clearly, I stand corrected on all accounts with nothing to offer this venue, and shall henceforth refrain from posting.

[Rhino]

I completely understand how you're feeling, but don't let it get to you. Everybody here, from the most experienced to the least, has at something to share.
I think it may simply be the specific wording of your post that Frank may have been keying off of, maybe not as much as the content. Looking at things from his perspective, It seems that some people are a little too eager to help, even though they may not have a full understanding on the subject matter. That's honestly a big problem with how impersonal the internet can be. Until someone sticks around for a little while, you can never tell the experts from those that wish they were. Opinions are great, but I'm sure you know what they say about them. There have been a lot of times that the advice given on a forum is just flat out wrong. As you stated, you know first hand the cost of bad advice. I hate to see people buying parts, and spending time fabricating something that wasn't the right fit for them. I'm not saying this is the case in your advice, just trying to offer a little background.

Stick around a little longer, and see what you think. Even though you may have a lot to offer, I guarentee you'll learn just as much here. Throw out your opinion, but prove to people that you know it by bringing the facts to back it up. :)

Moving forward to a little tech, the 4 link can be build to be a wonderfully nimble suspension in the corners. It just takes a little more knowledge and number crunching. "The 4 link" title covers a plethora of configuration options. What the fabricator working on your car may have been thinking of was a parallel 4 link typically seen on straight line cars. You also have the triangulated 4 link, and Satchell link that have been proven time and time again on the track.

A 4 link can be designed to go in a straight line, but that doesn't mean it has to be designed for a straight line. On a similar note, you can design a 3 link with a huge amount of anti-swat, and roll overseer characteristics that would make it handle better on the strip than in a corner.

If you're wanting to design a suspension without modification to a trunk pan, or while retaining your back seat, the 3 link gets a little difficult to package.
Suspension types are just like tools, there's a time and a place for each of them. All of them aren't the best fit for all conditions.

Do may dig a little more into your fabricators background, or ask specifically why he steers people away from the 4 link. I'd be interested to hear what he has to say.

[gizmo]

I bought a 1970 Chevelle SS, put a 540 merlin engine in it, built by one of the most reputable engine builders in the state, mechanical rollercam, rollerlifters, rollervalvetrain, 16:18 lash, 10.1 compression, custom canton road racing oil pan (with appropriate baffling and windage trays), it made 659tq @3500RPM and 683hp@4800RPM (mid range power), a jerico tranny, custom iron nodular rear, full negative roll suspension, truck arm rear, 13.5:1 quick ratio steering box, intermediate steering column, frame fully straightened/boxed/reinforced, ATL fuel cell with tons of pictures showing the build quality of the project, and the reputation of the names of those working on the car, and do you know what countless members offered me for this car when I did it?

They offered me less than the cost of the brand new negative roll suspension on the car. They felt everything I had just listed in that car was worth less than the the measly just-out-of-the-box front suspension it had (which I had just bought and put on the car).

I asked for a Chevelle that was unbeatable. At that time half of the recommendations they're making now weren't even a consideration. What do you think that says when someone recommends something because it's so great, you buy it just like they recommended, and when they want to buy those things from you (to save money) they're only willing to pay you 2 cents for every dollar you spend. I cannot tell you how badly it hurts me knowing I never had a chance to take this car out on the track with my dad. Such a waste, all of it, and I can't do anything about it now. I can't finish it and I can't sell it. It just takes up space. And it's terrible.

You want advice? Go to the local circle track and seek out a reputable fabricator that builds cars that win. If your circle track isn't that prominent then drive to one that is (we have a real prominent one nearby). Seek him out long before you buy anything! Give him a budget and a goal. He'll tell you which of the two are lacking, and once you've come to an understanding, he'll guide you down the right road. And if you're lucky, you'll get what you want and you'll get to enjoy it. Otherwise you might end up with a car that doesn't do what you want it to do and you might not be able to sell the parts back to the very people who recommended them because to them the parts are almost worthless.

Life is grand.

[ProdigyCustoms]

Gizmo, I am sure you have plenty of valueable information on various subjects. I made it clear I DID NOT want to run you off. But I also cannot let someone confuse the entire membership with incorrect statements.

Maybe instead of

"I heard"

Maybe you should have said

"my circle fabricator says"

Repeating things one hears as fact is a recipe for dissater.

Please, stay around and contribute.

So tell us more about your Chevelle, and show us some pics. What needs to be done to finish it?

[bret]

Sensitive crowd. Wait till you meet us in person!

A great way to see these types of suspensions in person might be to go to the MotorState Challenge in June. https://www.pro-touring.com/events/msc/

There will be several of us there as well as several examples of the suspensions in question.

I know a lot of these guys personally...they arent that scary...especially Prodigy. Give him a couple beers and he loosens right up!

[Mkelcy]

Gizmo: I hope you stick around and contribute.

What Frank failed to say is that (I'm guessing here) 80% or more of the tech information on this site is based on what people have read, been told or learned on sites like this, rather than actual hands on experience. There's nothing wrong with that if they are discriminating consumers of tech information and resist the temptation to go with the solution du jour. There are relatively few people who have actual hands on experience and technical knowledge about the subject matter of their posts (and I exclude myself from this category to a substantial extent).

As you read, you will learn who really knows what they are talking about on the basis of personal experience and technical knowledge and who doesn't. In the area of suspensions, I pretty much take anything (off the top of my head) David and Mary Pozzi, Norm Peterson, Marcus at SC&C and Chicane67 say as gospel. There are certainly many others who are very knowledgable that I just can't recall right now.

Frank also failed to mention the inordinate number of posts responding to "how happy are you with [name a part]" questions with enthusiastic reviews about the fabulous weld quality, etc., that end with "but my car's not on the road yet, so I don't know how it will actually work."

In other words, there was nothing out of the ordinary in the "tech" content of your post as compared to most of what shows up here and you were careful to let people know you weren't basing your statements on personal experience. That's actually pretty rare, and I appreicate it.

The four link pictured in this thread is clearly a drag racing piece. The trangulated 4 links Frank mentioned are designed more for handling, as is the AME 4 link. AME may also be making a 3 link for first generation F-bodies. Your observations about tuning a 3 link are spot on, something I'm going to have to delve into soon with my own car, which [rim shot] isn't on the road yet!

It's a little disappointing that no one in this thread urged the OP to try to analyze the causes of the his issues with the leaf spring rear suspension in his car before jumping on the DSE/G Link bandwagon. '68's with good staggered shocks and good leaf springs shouldn't wheel hop under acceleration and needn't ride harshly.

Too many of us throw new parts at an issue, rather than trying to understand what's happening with our cars and why. Rather than seeing if there's a better, cheaper fix and refining what we have, we run out to buy and bolt in the current "hot" setup.

Speaking of which, take a look at this post by Mary Pozzi, showing what can be done with carefully tuning (your point Gizmo) a leaf sprung, stock subframed car: https://www.pro-touring.com/forum/showpost.php?p=504916&postcount=78

[JRouche]

The four link pictured in this thread is clearly a drag racing piece.

Shhhhh.. Shes not so drag queen anymore :rotfl: JR

https://static1.pt-content.com/images/pt/2009/05/c-3.jpg

[Mkelcy]

Shhhhh.. Shes not so drag queen anymore :rotfl: JR



LOL, glad to see the Watts link in there. I didn't see so much as a panhard bar in the first shot. Any bind issues?

[gizmo]

Hey, anyone have a link to the design decisions for "Bad Penny"? I'd be curious to see why they opted against something akin to a fifth coilover system with birdcages.

Beautiful car.

Also, maybe something that would show where the mounted the coilovers to the housing? Anyone know where the instant center falls in comparison to the neutral axis? Geez, I'm guickly touching on things that a really out of my league here. (Sorry).

I wish I could find a picture of an MRE system, I almost forget what they look like.

I must say, I'm surprised I was able to find as much about the car as I did, I know many owners go to great lengths to keep these sorts of things secret. That says a lot about the owners!

Also, did they relocate the engine? I've never seen uppers like those (but then again I've only seen custom uppers on A bodies)

[Vegas69]

A forum is made up of opinions by folks that have experience or just shoot from the hip. At the end of the day I believe those that have actually installed the products and hopefully put them to the test. It's pretty clear that a Lateral Dynamics 3 links works great in Penny and the Quadralink works great in the DSE 1st and 2nd gen. For that matter the air bar has been really competitive as well. It's pretty apparent that Bad Penny and the DSE cars have been tweaked and tested way beyond most around here. I have first hand knowledge with a DSE subframe and a G Bar. The car rides and handles fantastic. After one autocross I have already torn a bushing in the upper control arms that control side to side movement. I am currently upgrading to a teflon/kevlar end links on both ends of my triangulated arms and the rear end links on the lowers. This will eliminate the bind caused by the stock bushing material used in the G Bar/Air bar. Most of us around here are happy to share ideas and solutions. It's not like we're competing for the Sprint Cup trophy around here.

[Mkelcy]

Hey, anyone have a link to the design decisions for "Bad Penny"? I'd be curious to see why they opted against something akin to a fifth coilover system with birdcages.

Beautiful car.

Also, maybe something that would show where the mounted the coilovers to the housing? Anyone know where the instant center falls in comparison to the neutral axis? Geez, I'm guickly touching on things that a really out of my league here. (Sorry).

I wish I could find a picture of an MRE system, I almost forget what they look like.

I must say, I'm surprised I was able to find as much about the car as I did, I know many owners go to great lengths to keep these sorts of things secret. That says a lot about the owners!

Also, did they relocate the engine? I've never seen uppers like those (but then again I've only seen custom uppers on A bodies)

LOL, okay, now you're just trying to show off.

If by "uppers" you mean the front UCA mounting points, those are standard on the 21st Century Street Machine subframe Penny uses.
https://static1.pt-content.com/images/pt/2009/04/uca-1.jpg

They are set up with circle track slugs so you can raise or lower the UCA mounting point. Based on my own 21st Century Street Machine subframe, I don't think the engine has been significantly relocated.

The rear end is a Lateral Dynamics 3 link. You'll find lots of information about it here: http://www.lateral-dynamics.com/

[gizmo]

I must've been looking at a totally different car because the front subframe I saw looked nothing like that one.

ROFL

And no, I wasn't trying to show off, I figured since you guys have already deemed me stupid and encouraged me to continue posting in hopes I might learn something, I figured I'd start asking questions I didn't have answers to.

I really know very little, and I happily admit that. Heck, my fabricator loved to rub that in my face. (He called me a dummy once because of a misunderstanding I had about the transmission -- the whole thing had me in tears [I wanted the car finished before my dad was too sick to drive it]).

He still has me badly worrying whether the "violent torque reaction" of the truck arms upon throttle application (being rigidly mounted).

[MrQuick]

Who called you stupid...damn them...at least they didn't call you an EXPERT.

Is this something you want to kit together or install.

Call AME, last time I spoke to Craig he was working on a 3 link rear frame for F bodies. I might have been dreaming though.

Welcome to the site and stay a while. take you shoes off but don't drink the water.

[gizmo]

My sentiments exactly.

[Damn True]

Hey, anyone have a link to the design decisions for "Bad Penny"? I'd be curious to see why they opted against something akin to a fifth coilover system with birdcages.



If you are talking about what I think you are talking about

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

The answer is because on a roundy-round car you use those to tune the amount of bite/slip in the rear.

When you are turning left AND right you don't.


Roundy-round suspension theories are VASTLY different than those that are used to turn left and right.

[zbugger]

LOL, okay, now you're just trying to show off.

If by "uppers" you mean the front UCA mounting points, those are standard on the 21st Century Street Machine subframe Penny uses.
https://static1.pt-content.com/images/pt/2009/04/uca-1.jpg

They are set up with circle track slugs so you can raise or lower the UCA mounting point. Based on my own 21st Century Street Machine subframe, I don't think the engine has been significantly relocated.

You are correct in that they are standard on the no longer available 21st Century front subframe. The upper arms are C6 Corvette parts. The mounting points have been modified and changed.



...Call AME, last time I spoke to Craig he was working on a 3 link rear frame for F bodies. I might have been dreaming though.

Welcome to the site and stay a while. take you shoes off but don't drink the water.
Actually, I think he said they've got one for the first gen Camaro, and are looking at one for the 2nd gen. And I agree with you on not drinking the water. Just look at what's happened to us after we were warned...

Gizmo, welcome to the site and don't take things too personal around here. There are many opinions, and you know what they say about those. There are many different kinds of experience around here. Many of us know what we're doing. Not saying I personally do, but others do. And also know that not all car builders/fabricators know everything about everything. There are several accounts of people getting misinformed by a builder that one part is better than another, but that's often based on what the builder actually wants to install/what will make him more money. Some guys just don't know. Good example is the guys that made the show "Pimp My Ride" saying ON TELEVISION that nobody makes wheels for a '65 Mustang anymore and that the Giovanna wheels had to be custom made. Really? Wow... I didn't know that. Good thing I don't believe what I watch on TV, huh? Anyhow, we're all here to help. I hope you enjoy what we really have to offer here.

[gizmo]

If you are talking about what I think you are talking about

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

The answer is because on a roundy-round car you use those to tune the amount of bite/slip in the rear.

When you are turning left AND right you don't.


Roundy-round suspension theories are VASTLY different than those that are used to turn left and right.That is definitely a type of fifth coil over but I think the ones I have seen used are quite different in application (although I can't find anything that resembles what I've seen and for some reason the names I do recall I find nothing about (hoffman absorber, MRE system, etc.) so I can't even see if what I think I remember is what it is...

But I think you're right, the fifth coil over (when used with a torque arm) was intended to give the 3 link all the benefits of a torque arm with the same benifits of a leaf spring without the drawbacks of either. Without birdcages though, none of that could be possible, as the rear tires would be unloaded during braking by the fifth because the downward motion on the torque arm would cause the axle housing to move upward. But I suppose if roadraced 3 link can do without a torque arm (and thus without a fifth coilover) then the fears I had about my truck arm responding violently (unfavorably) to hard throttle application is insufficiently grounded (as I believe truck arms are widely viewed as poorly suited for short track applications because of their violent throttle response)

[JRouche]

LOL, glad to see the Watts link in there. I didn't see so much as a panhard bar in the first shot. Any bind issues?

No bind issues yet???? Have to see her on the road though. I moved the rear end up and down, on each side, (had to block the non supported side) to check for rebound and compression, side to side and binding. As far as I can see at 5 degrees of body to frame roll the 4-link is compliment. Now... There is a pretty firm roll bar in there to. I checked the roll compliance without the bar. Just to see how much the 4-link bars were binding.

With a reasonable 5 degree roll the 4-link is still complient, meaning there isint any bind from the 4-link bars. After about 5 degrees they do start to take some of the torsional load. Five degrees is alot really, for body roll. At five degrees, or past that I want ALOT of support. And I get that with the sway bar I have. And the bushings on the 4-link actually start working.

Oh, were you asking about binding from the watts link?? If so.. Yeah, no bind at all.. It wont, the entire rear end would have to drop out before that watts link binds. Its silky smooth. JR

[Damn True]

But I suppose if roadraced 3 link can do without a torque arm (and thus without a fifth coilover) then the fears I had about my truck arm responding violently (unfavorably) to hard throttle application is insufficiently grounded (as I believe truck arms are widely viewed as poorly suited for short track applications because of their violent throttle response)

I would suggest you utilize the search function. The various benefits and drawbacks of each type of suspension (including truck-arm) are discussed in great detail in a number of places.

At the end of the day though you can be certain of one thing; A properly engineered, properly installed and well sorted 3-link or 4-link will work well. The differences in performance will not likely be apparent to anyone unless they have a seriously legit driving resume.

[parsonsj]

A properly engineered, properly installed and well sorted 3-link or 4-link will work well. The differences in performance will not likely be apparent to anyone unless they have a seriously legit driving resume.Exactly. Do use the search feature. There are lots and lots of threads on this and related subjects.

jp

[Rhino]

That is definitely a type of fifth coil over but I think the ones I have seen used are quite different in application (although I can't find anything that resembles what I've seen and for some reason the names I do recall I find nothing about (hoffman absorber, MRE system, etc.) so I can't even see if what I think I remember is what it is...


What you're refering too I've always heard described as a decoupled torque arm. That might help in your searching.

I've not had any experience with it, although it does look intriguing.

[Norm Peterson]

Hey, anyone have a link to the design decisions for "Bad Penny"? I'd be curious to see why they opted against something akin to a fifth coilover system with birdcages.
I'm going to guess that the 3-link being (arguably) the best of the "simple" arrangements had a lot to do with it. It was standard fare in SCCA Trans-Am, which ought to say something.

The more complex arrangements used in circle track racing could end up being the next level within a rather narrow segment of the PT world, if for no other reason than because you can separate the acceleration reactions from the braking reactions and tune the geometries separately. Pretty much, the "decoupled torque arm" represents a first step into this realm, and since there seems a little more to it than just bolting it up and driving away there has been a "learning process" as far as tuning it goes. The phrase "picking oneself up by the bootstraps" comes to mind . . .

I suspect that there's a lot of useful stuff that can be borrowed from the circle track racers, with the stipulation that somebody is going to have to sit down and figure out how to best adapt it (and everything that's at all related) to both left turns and rights given that all of the roundy-round experts naturally concentrate on turning left.


For the Chevelle, why not optimize it around the way it is rather than chase any illusion of "ultimate"? Leave whatever happened, however painful it may still be, in the past. Truck arms aren't all that bad, and some of the disadvantages are minimized as car weight goes up (I am assuming that your Chevelle is somewhat heavier than an F-body or Mustang tuned for comparable purposes). Truck arms are predictable, and that's a good thing. You don't have to take my word for it - the various NASCAR driving experiences wouldn't be letting folks with zero known competition-level driving experience drive cars so equipped at 135+ mph between hard concrete walls within eight laps otherwise.

Conventional autocross wisdom as far as where the improvements come from is (1) driver, (2) tires/wheels, (3) everything else. Fix the driver with (lots of) seat time, put good tires on it, and tune the "everything else". Variability in items (1) and (2) will cover for a lot of (3) being less than "ultimate".


Norm

[gizmo]

For the Chevelle, why not optimize it around the way it is rather than chase any illusion of "ultimate"? Leave whatever happened, however painful it may still be, in the past. Truck arms aren't all that bad, and some of the disadvantages are minimized as car weight goes up (I am assuming that your Chevelle is somewhat heavier than an F-body or Mustang tuned for comparable purposes). Truck arms are predictable, and that's a good thing. You don't have to take my word for it - the various NASCAR driving experiences wouldn't be letting folks with zero known competition-level driving experience drive cars so equipped at 135+ mph between hard concrete walls within eight laps otherwise.Well for one, the Baer brakes I bought require a 17" rim, which need to be custom made for the respective offsets required (I think 4.5" and 5" for front and rear respectively). The rear was built so that the slightly wider rear tires are nearly perfectly in line with the narrower front tires (so that they won't nail the frame full lock and so that the front and rear tires follow a nearly identical driving line (important to handling)); regardless those rims are very expensive and the tires are just as expensive. If I swap out the front negative roll suspension and braking system then I could use a lower spindle (with a new custom AFCO front suspension built by the fabricator) so that I don't need to run 5+ degrees of camber just to get the car competitive. Secondly, the coil overs require a 900 lb spring with a big block in the car (which when I told GW i would be simply racing with the car they sent me a 550lb spring even though I told the guy I had a 502 big block. (By the time I got on the phone with doug to sort it out he said it would cost me another 1K to get the springs I needed and at that point, between the additional cost of the springs and the rims and the tires, I could buy a newer better suspension, rims, and tires for less). Even though the big block is 2" lower and 1.5" backward (NASA rules won't allow movement of the firewall so the engine is as far back as it will go); if I could afford custom headers (which I can't because I can't afford anything and that's why the car has languished all these years) then I could probably lower the motor another 2-3". So now, with this new suspension and new brakes, I can have a move competitive front suspension, with ordinary springs and shocks, with 1-2 degrees of camber at most, and the different braking system will allow a standard 15" rim with standard bias ply slicks. Regardless, with the power the car makes, it still needs a full fledged roll cage (the fabricator swears without it the frame will be pretzeled with one hole shot), it still needs a drive shaft, still needs a few afco steering components (centerlink and a few other pieces connected to it) and all the plumbing and electrical stuff. At that point, I'm fairly close to a finished produt, but at the point I'm about 10K out. I just hope the motor doesn't die between then and now just sitting around through the seasons. (It's been drained of all fluid and I've covered everything up). sigh...

[Bryce]

about your motor, Remove valve spring pressure or rotate the engine every once and awhile.

[Bryce]

this post got a little off topic.

so in conclusion, every suspension has pros and cons. and driving style may impact the type of suspension you want. Money is also a consideration. But it does seem that any suspension can go fast. Look at 65 mustang with leaf springs. they handle very well. just like a 95 mustang with a 4bar rear suspension that can have bind at the extremes. a 3link can have great articulation and give great anitsquat numbers if tuned for that.

i do think a properly desinged 3link is the most versatile if tuning was built into the design. if mounting points can be changed as well as the lengths of the links.

[seekins]

What about jake's rear suspension? From what i could find it looked like a solid setup. As good as a 3 link, but simple to install and a bit more friendly to set up..let me know if im off base here. I have a front and rear setup on the way for my 68.