Corvette Suspension Swap-Sway Bars?

[duwem]

Flat Out Engineering tells me they dont have a solution for a sway bar for C4 vette suspension for 47-54 trucks.

How do they expect the thing to go around corners without a sway bar??

What are you guys using?

Would like to do front and rear, but for sure front to start.

Thanks

[tmoble]

the Corvette suspension is modern design, has a high roll center. Doesn't need a roll bar as much as like an MII or other clip solution. Try it, you might like it.

[OKGMC4]

Part of the design in that monoleaf suspension is that it has some antisway properties built in. That's why the C4 uses such a smaller sway bar than most other cars. I PROMISE it will handle better than the stock suspension did!

[duwem]

Thanks for the input guys.

Few things though:

A) the earlier year C4's (84-87) were not as good as the later years (88-96) for suspension geometry. I have the earlier.

B) I'm ditching the monoleaf and puting on coil overs

C) the stock corvette had front and rear swap bars from the factory

D) a truck is going to have a higher center of gravity than a corvette.

I want this thing to handle curves. I plan to autocross it and also want it to be fun to drive, not just in a straight line.

[Houston54]

I am installing a 89 C4 IRS on my 58 and plan to use the stock sway bar. The installations I have reviewed install it over the top of the frame. There is a picture with this installation on the progressive automotive website.

[NICK51]

See if this might help

http://www.classicparts.com/1947-54-...ctinfo/74-803/

-Nick

[duwem]

Houston,
The earlier frames (47-54) were shaped a lot different than the later ones. I believe the stock sway bar would sit right on the frame rails, and with the rails tapered it would not be wide enough.

Nick,
That might work for the front, would need some measurements. Have not investigated fitup of the stock vette bar yet, but my assumption is it wont work on the truck.

[Houston54]

"The earlier frames (47-54) were shaped a lot different than the later ones. I believe the stock sway bar would sit right on the frame rails, and with the rails tapered it would not be wide enough. "

Granted the AD frame is different than the task force but the width is actually narrower in the rear than the task force. There would not be any issues installing the sway bar in that manner on a AD frame that I can see.

The sway bar would install over the top of the frame rails but under the bed. There may be a need to trim some bed supports but nothing drastic.

[tmoble]

>>> "the earlier year C4's (84-87) were not as good as the later years (88-96) for suspension geometry"

What's different about them? All the major parts interchange. Fronts have a taller spindle or something?

[tmoble]

I have an '85 C4 rear under my truck, have the anti-roll bar left over. you can have it for shipping if you need it.

[lonelywanderer]

i know the earlier gen c4 ifs has smaller brakes compared to the later ones but i never read about them being different

[duwem]

Read it in the book "Chassis Engineering"

Did some searching and someone is talking about it here too:

http://forums.corvetteforum.com/auto...ll-center.html

[OKGMC4]

Some people prefer the earlier ones because you can fit a little smaller wheel on the smaller brakes. Not everyone wants the pro touring look. I couldn't figure out how to make a rear bar fit right on mine because the rear tank was in the way. Newman car creations did it but no rear tank - and progressive did it but used a front bar on the rear, over the frame rails.

I think you could make some rough sketches and with some careful measurements find a bar in the boneyard that might work. You'd have to make custom end links for the A arms but obviously fabrication is not out of the question. Why do you need the coil overs. Chevy spent like a bazillion dollars engineering the suspension and the vette stuff is top notch. I guess you really want the adjustability / tuning option.

[duwem]

Ya, I'm not too concerned about old vs new geometry.

I have had numerous calls to both Flat Out and Progressive and both have bene doing this for 15 plus years and both sell coilovers with their kits and dont recommend the leaf springs under our trucks. They say they are too stiff and dont allow for any adjustability for differnt combos. I like the adjustability of coil overs, and also the fact that they look a lot better.

I do have both vette sway bars, will have to look at the front for the rear. My guess its it would be too stiff.

Funny you mention looking at junk yards, just thought of that today.

End links are no problem, I can figure something out, just need a bar that fits right to start with.

By the way I plan to autocross my truck. That is why I went with the vette stuff from the get go. I know a sway bar up front will be necessary for it to go round corners hard.

[duwem]

Are you refering to the stock front or rear bar?

I looked at putting the stock rear bar on the rear and with the tapered frame rails it just did not look like it would work out.

[OKGMC4]

Here are two pics on a task force. One is of a rear bar mounted under rail and one is a front bar over rail. Not sure how it would work on an AD. It's funny how some places suggest coil overs and others don't - Newmans actually suggest staying away from them. I'm shaving the spring sides for height and a softer ride because it's cheaper, but no autocrossing for me. I just want to cruise. I went with the vette stuff because it was the cheapest way to get 4 discs, rack steering, huge weight savings, a built in lowering kit, and easy replacement parts. Mustang II and 9 inch fords with 4 link kits were too high for me.

[solidaxel]

Originally Posted by OKGMC4

Here are two pics on a task force. One is of a rear bar mounted under rail and one is a front bar over rail. Not sure how it would work on an AD. It's funny how some places suggest coil overs and others don't - Newmans actually suggest staying away from them. I'm shaving the spring sides for height and a softer ride because it's cheaper, but no autocrossing for me. I just want to cruise. I went with the vette stuff because it was the cheapest way to get 4 discs, rack steering, huge weight savings, a built in lowering kit, and easy replacement parts. Mustang II and 9 inch fords with 4 link kits were too high for me.

Did you get all that rubber on the outside of the bed and under the fenders?

[tmoble]

the stock spring is certainly not too stiff under my 57 SS. And that's really a laugh on the adjustability gripe deal. You know those long bolts that run from the spring to the top of birdcage? I have them in 9, 10 , 11 and 12". They're 1/2" grade 12 with Nylock nuts. I can change the height of the rear 4" without changing the ride height of the suspension at all. Less than 10 minutes. Try that with coilovers. lower control arms and halfshafts are dead parallel to the ground. Has the stock Bilsteins and steps nicely over any bumps, sharp driveway cuts, rough road, etc, etc. No tramping, skittering on rough corners, all that jazz I used to have when I had the 79 T/A Ws-6 rear axle and springs under it. Couldn't be better. IMO, YMMV, all that.

[tmoble]

Would they be able to sell you any parts if they told how good the stock setup is? Wonder if that's why they tell you you have to have all these trick parts and the stock stuff is no good?

[duwem]

Here is C4 vette suspension under an AD (47-54 truck). Not how the rear width of the frame is significantly different than the TF trucks (as pictured above).

I have already decided I'm not running the leaf springs.

[48 GMC BURB]

DUWEM
Do you have more pix of your install I have a 96 vett going under a 51 AD

Originally Posted by duwem

Here is C4 vette suspension under an AD (47-54 truck). Not how the rear width of the frame is significantly different than the TF trucks (as pictured above).

I have already decided I'm not running the leaf springs.

[duwem]

Have not touched the truck this year at all. Too many other irons in the fire.

[tmoble]

duwem,

Looks like you have some kind of tie-rod flip kit in there? It eliminates the leaf but lowers the tie rods so you don't have to notch the framer for them. That's the worst part of my install.

Looks like the early frame has more kick-up over the axle too. big advantage.

[1 bootlegger]

Have you looked at Welder Series Inc. Sway bars? Just a thought. Are you going to race your truck at Elkart Lake, Road America ?http://www.welderseries.com/blog/onl.../sway-bar-kit/

[NICK51]

tmoble-- i have the toe bar flip kit on my c4 install, it worked out great check out my album

http://s1112.photobucket.com/albums/k483/nick5110/