69 Front Suspension - Need Help

[gggoad]

I am building a 69 PT. I am looking at the following options for front suspension:
DSE Speed Kit 3
Fat Man Subframe
Global West Cat 5

Everyone claims theirs is the greatest, I see advantages to each whether it be cost, function, etc. I am running a built 540 - I want the car to be able to pull close to 1g on a skid. Has anyone "done" this and could you share your thoughts. I need reality not theory! I am drained on theory :).

BTW, I am running a Morrison Tri-4 link, DSE mini tubs, 19x12/18x8 Intro's.

[baz67]

Dump the Fat Man and, if you can, the BB and you may get close the 1g. Fat Man is a hotrod shop and it is engineered for hotrods. Both DSE and GW are engineered for handling.

[Travis B]

all of those options have been beat to death on here.....try the search button

[EFI69Cam]

Dump the Fat Man and, if you can, the BB and you may get close the 1g. Fat Man is a hotrod shop and it is engineered for hotrods. Both DSE and GW are engineered for handling.

What is the weight diference between a AL head BBC and a iron head SBC? 30lbs? BBCs get a bum rap for weight when the really don't weigh that much more than small blocks.
I'd bet that my car with a bow tie based 540 with al heads and unisteer rack does not weigh any more than most small block cars with AC and cast iron steering gears.
The only engine that has a real weight advantage is the LS1.

[baz67]

Apples and oranges. Since you asked:

Chevy small block V8 575 (generic for '60s-'70s motors)
Chevy small block V8 535 (1) ('59 Corvette 283 w/alum. intake)
Chevy small block LS1 460 (185)
Chevy 5.7 industrial V8 434 (182) '99 iron long block w/water pump only
Chevy LT-5 DOHC 5.7 600 (122)
Chevy L98 5.7 V8 600 (122)
Chevy V8 348/409 620 (1)
Chevy V8 348/408 655 (83)
Chevy big block V8 685 Mark IV
Chevy big block V8 --- Mark V
Chevy 454 675 (10)
Chevy 7.4L V8 656 (183) iron, no intake, exh, carb, starter
Chevy 427 ZL-1 550 (35) all-aluminum, "20# lighter than SB"
Chevy 6.5L Diesel V8 644 (183)
Chevy 400 SB 470 (235) aluminum heads and intake, no acc. or wp
Chevy 396 BB 610 (235) iron heads, alum. wp and intake,

It does not take much mass to really decrease the effectiveness of the front tires. Fc = mv2/r, where Fc = centrifugal force, m = mass, v = speed, and r = radius. By all means put a BB in your car if you want to. Just do not be fooled into thinking it will have the same skidpad numbers if you had a SB in the same car. Simple laws of physics dictate that it will not.

[EFI69Cam]

I've seen that list before, its somewhat useless, as there is no indication as to the state of dress of each engine.

Hotchkis recommends their SBC spring for aluminum head BBCs. The difference is less than what most expect.

[Damn True]

Not to mention the impact of where that weight is relative to the CG of the car, and relative to front axle centerline.

[TitoJones]

I have ran both geometry numbers for the DSE level 3 system, and the GW cat 5, but our AFX spindles by themselves have better geometry than either, for a fraction of the price. The FatMan is pure street rod stuff, not optimal for handling. Tyler

[baz67]

I've seen that list before, its somewhat useless, as there is no indication as to the state of dress of each engine.

Hotchkis recommends their SBC spring for aluminum head BBCs. The difference is less than what most expect.

You are not seeing my point. You are comparing apples to oranges. You compare your stripped down BB to a all iron SB with A/C and still your BB is heaver. Now being realistic most SBs will have AL heads in a PT car. That will make the weight diffence around 100 lbs. That is not chump change when you put velocity into the mix. The SB will beat the BB in every way except the 1/4 due to the more power of the BB and the front tires really do not come into play in the 1/4 as much as on the skid, cones or road coarse.

My original point was it will be easier to hit the 1g mark with a SB and that still holds true. You cannot fool physics.

[EFI69Cam]

You are not seeing my point. You are comparing apples to oranges. You compare your stripped down BB to a all iron SB with A/C and still your BB is heaver. Now being realistic most SBs will have AL heads in a PT car. That will make the weight diffence around 100 lbs. That is not chump change when you put velocity into the mix. The SB will beat the BB in every way except the 1/4 due to the more power of the BB and the front tires really do not come into play in the 1/4 as much as on the skid, cones or road coarse.

My original point was it will be easier to hit the 1g mark with a SB and that still holds true. You cannot fool physics.

You are right. If he wants 1g from a 1st gen he will need a lighter front end.

My point is that the average owner/builder of a PT car is not pushing the performance envelope to where a SB is going to make a difference.

[Yenkostyle]

Of course you could always go against the grain and do this:http://www.hotrod.com/featuredvehicles/67759/

Set the motor back and do some more work to possibly hit the number you are looking for...

[gggoad]

Guys, I appreciate the replies to my post. Losing the 540 is simply not an option, I have spent a ton of money on the motor - and I simply want the horsepower offered. The real question is, how do I compare the different front suspension types offered? There are so many options in a-arms, spindles, gear box etc., how does a guy make an educated decision?

Will the simple addition of a spindle (AFX), really perform better than a complete suspension system - such as the DSE? There are so many claims out there.

Can I get some feedback from you guys on what you are using, how does it work, etc.?? Is there any real-world stat's that back up any of the claims from these different manufactures?

[EFI69Cam]

Guys, I appreciate the replies to my post. Losing the 540 is simply not an option, I have spent a ton of money on the motor - and I simply want the horsepower offered. The real question is, how do I compare the different front suspension types offered? There are so many options in a-arms, spindles, gear box etc., how does a guy make an educated decision?

Will the simple addition of a spindle (AFX), really perform better than a complete suspension system - such as the DSE? There are so many claims out there.

Can I get some feedback from you guys on what you are using, how does it work, etc.?? Is there any real-world stat's that back up any of the claims from these different manufactures?

I'm in the same boat as you, I have a 540 and it is not going anywhere.

The low buck option is GW uppers (for the caster) and the ATS spindles with Hotchkis springs. I ran my car with a 454 with these parts (minus the spindles) and thought it drove really well.
Since the motor is out now, I am going to install the DSE coilovers.

[baz67]

I'm in the same boat as you, I have a 540 and it is not going anywhere.

The low buck option is GW uppers (for the caster) and the ATS spindles with Hotchkis springs. I ran my car with a 454 with these parts (minus the spindles) and thought it drove really well.
Since the motor is out now, I am going to install the DSE coilovers.

Ding, ding we have a winner.

[TitoJones]

Will the simple addition of a spindle (AFX), really perform better than a complete suspension system - such as the DSE? There are so many claims out there. I don't make 'claims' I just give hard facts about products we've tested. I've ran the geometry of stock, guldstrand mod, and the DSE coil over kit, and our spindle by itself gives you better gamber gain than any of them. Plain and simple fact. Tyler

[gggoad]

Tyler, please don't take offense, I certainly do not mean to offend anyone.

When I talk to DSE, they claim a stock spindle is the only way to go. GW claims a tall spindle is the only way to go. Heidts tells me their dropped tall spindle is the best on the market. It is VERY confusing to me. I have always worried about 1320 feet in a straight line - much less complicated.

What is your recommendation as far as the rest of the front suspension, using the AFX spindles? I would like to keep the front suspension around $3K.

[vanzuuk1]

The one positive thing is that any of those setups installed and setup properly will be a huge improvement from stock. Keep researching and you will find a company you like for various reasons. Stick with one company if you can, and be realistic about what you plan to do with the car. Plan to do some tweaking once you think the car is "done" , alignment, ride height, etc.

[gggoad]

Tyler, good talking to you - I really appreciate your insight and look forward to getting the parts to install. Thanks again!

[EFI69Cam]

The one positive thing is that any of those setups installed and setup properly will be a huge improvement from stock. Keep researching and you will find a company you like for various reasons. Stick with one company if you can, and be realistic about what you plan to do with the car. Plan to do some tweaking once you think the car is "done" , alignment, ride height, etc.

Not to argue, but sticking with one company is not always the best.

For instance DSE makes a fine coil over conversion, but their option of using the stock spindle with relocated a arm mounts is not as good as stock locations with a tall spindle.
GW's tall spindle will work with their brake kits only.

You need to research everything.

[TitoJones]

I agree with the above statement. There is yet to be the end-all-be-all suspension setup from one company that will work with a stock sub. I'm a big fan of the DSE and GW control arms, I like Lee for P/S components, and our spindles are the way to go for most of you.
In fact, we took the 'gather up as many companies making cool stuff' into our Chicane-LM front suspension. It uses GW, Lee, Moog, Baer, ATS, and some others to make a very track capable suspension kit that works great on the street too.

Tyler

[HOSTILETAKEOVER]

Nobody has mentioned the C4 and C5 suspensions on aftermarket subframes. Is this the standard to aspire to?

[vanzuuk1]

The reason I said stick with one company is for tech support, most companies wont help with tuning questions if you mix and match parts. For the guys who know enough thats not an issue, but for some its helpful to have a source for info.

[gggoad]

c4/c5 stuff costs about 6500 all said and done. I am looking at more like 3500 including brakes.

[baz67]

Nobody has mentioned the C4 and C5 suspensions on aftermarket subframes. Is this the standard to aspire to?

Why? Just because one has Corvette parts does not make it better. It makes it more expensive. IMHO, no it is not the standard. It is only an option for someone that wants to say they have Corvette parts on their car. A well thought out and modified stock subframe will have outstanding performance.

[Jinks]

hmm.. so where exactly do you buy these ATX spindles?

Im not 100% on what to do with brakes as i will be converting from drum to disc. Can i still run a conversion kit with these spindles?

And running the G-mod, the GW upper control arms, and these spindles will all work together?

[baz67]

hmm.. so where exactly do you buy these ATX spindles?

Im not 100% on what to do with brakes as i will be converting from drum to disc. Can i still run a conversion kit with these spindles?

And running the G-mod, the GW upper control arms, and these spindles will all work together?

If you mean AFX spindles, look at www.t56kit.com. What conversion kit are your talking about?

GW arms, yes. You can do the Guldstrand mod only if you use the stock height AFX spindle. The AFX tall spindle does give a better camber curve over the Guldsrand mod.

[Jinks]

sorry, by conversion i mean drum to disc.

i guess seeing as ill already have a disc spindle all i will need to change is the master cylinder, and add in a proportioning valve.