lsx24

iTrader: (45)

My writeup's been moved here: https://ls1tech.com/forums/suspension-brakes/842240-fbody-street-suspension-setup-review.html

Foxxtron

iTrader: (1)

Outstanding! You've pretty much hit the nail on the head with concerns to ridding the troubles of the stock handling equipment with little compromise, some extra money spent, and without making certain handling properties worsen. For anyone who notices this thread, this car's suspension contains the slight improvements over this car, which I believe is almost a de facto minimum workable standard for this generation F-body:

http://www.1le.net/docs/tittermary.jpg

later on, there was this improvement as well:

http://www.1le.net/docs/2001_1le.html

now, this is the first write-up that I've seen that's really harnessed the true capability of what's been applied above, with a few inexpensive, but very effective DIY parts for the PHB, and no added dead/excessive weight.

I too had my street vehicle set up similar to yours, however I had Koni DA's (kind of like the 1LE, but I found the compression adj. to be a waste, even for some AX apps). The Koni SA is really the better of the two (SA vs. DA), since there isn't really much differences to be changed with concerns with unsprung weight.

My street Z28 has different parts now, since it might be the vehicle that will inherit the responsibility of my current track car (maybe), but if I had to return to a street performance setup, I'd easily go right back.

DONAIMIAN

iTrader: (18)

Verry good info. Im happy to see someone who realisticly knew what they wanted without lying to themselves and put together a well thought out set up.

treysoucie

iTrader: (4)

did this setup alter your stance?
im looking at a combo just like this for my SS

UAZ28SS

iTrader: (2)

Mother of god... you car sounds SICK!

GREAT write-up on the suspension pieces, too. I have completely rebuilt my entire suspension to achieve the "canyon carving" abilities you speak of. Man... WHAT a difference!

99HOSS

I just finished your entire article and it is well written and fairly informative.

But I have one (or two) concern(s) with some of it's content.

First, the PanHard Bar is primarily for maintaining your differential in a somewhat lateral center. The adjustable kind is necessary for cars that are lowered, in order to maintain that lateral center. It really doesn't have that much to do with curing 'sidestepping', as that is more a sign that your tires are not staying planted to the road surface. So if your springs and bars aren't up to the task of throwing the car around, then you would need to do some of the other mods you performed.

Basically the 3rd & 4th Gen F-Bodies are the same basic design in the rear suspension area, so I'm not exactly sure what the benefit was with running a 3rd gen shock.

As far as the 1LE rear lower control arm, they are just a stiffer material in the bushing, they'll still bind under hard cornering. Rod-ends, as you mentioned, are the only way to eliminate bind.

My track car is based on an American Sedan (A/S) classed car found in SCCA racing. It has 850 lb/in springs up front, 175's in the rear. 36mm front bar (stock WS6) and a 19 (I believe also stock WS6) in the rear and the rest of the suspension is completely adjustable with components from Ground Control, Guldstrand, TPIS and Spohn. It definitely doesn't have any 'street' manners left in it, but it is a blast to drive.

Just as a point of reference to my experience over the past number of years, I've crewed for teams that have run 3rd & 4th Gen F-bodies in A/S, Camaros in Touring 2 (T2), Corvettes in Touring 1 (T1) and both Corvettes and GTOs in the Speed World Challenge GT series.

These cars (late model F-bodies) are a great handling car with a little massaging of the suspension. And as you pointed out, you want to research your project before buying anything for the car. Ask yourself 'What do I want this car to be able to do?' before spending a dime and Sam Stano is volumes of info on setup. He's been there, driven that and knows what works for your application.

Foxxtron

iTrader: (1)

The only benefit is cost savings, and FWIW, Sam mentioned he uses the 3rd Gen Koni SA when he competes, and the 4 settings are good enough for the rear spring rates he uses. Otherwise, the 12 way adjustibility through adjusting directly at the rear shock mounts from inside the cabin makes the 4th Gen Koni SA superior, if not just "enough needed."

They will definitely bind a little more than the non-1LE bushings, but that's due more to the fact that the rubber voids are completely eliminated, not because the rubber being used is actually of a higher durometer. AFA rod-ends they have no bind, until the bushing (or what I call spacer) reaches the maximum misalignment angle (making contact with the outside race of the bearing retaining structure), which can be rare.

Not too sure if you're saying that a stock WS6 uses a 36mm bar, because a stock WS6 uses a 32mm front bar, with exception of some later packages available that included SLP's 35mm front coupled with a 21mm rear. AFA those WS6's that had a 19mm rear, yes they did, provided they had the 32mm fronts.

99HOSS

Foxxtron - I figured it was just a cost savings. It's one of the reasons I went with a 3rd Gen to begin with. And Sam does know what he is talking about, too.

And as far as the 1LE bushing in the LCA, it is actually of a higher durometer, not just a design difference.

"rod-ends they have no bind, until the bushing reaches the maximum misalignment angle" - true statement. My track car uses rod ends on the component side and poly on the chassis side for the PHR and the LCA. Both adjustable for length.

'AFA' the front bar, the 3rd gen TransAm, with the WS6 package, came with the 36mm front bar, as well as a WonderBar and a quick ratio steering box. That's where the Guldstrand parts come in. He's the only performance shop that I know of that carries an actual 36mm bushing. I also use his endlink kit.

Foxxtron

iTrader: (1)

I get what you mean, however, since this is a 4th gen oriented thread, that's why I had to clarify. I know you're being objective, however I'd also like to clarify to other readers that I never said nor implied that Sam doesn't know what he's talking about.

AFA the 1LE bushings, between the non-1LE 4th Gen and the 1LE, are they actually different durometers, or is it just their outer diameters being different? With an ASTM durometer test, there was no differences in durometers of the materials themselves, and not any difference when compared to the Rubber Howe racing bushings I use on my trailing arms (the ones that the links in lsx24's postings lead to). The rubber howe bushing tends to bind more than the two due to the smaller inner and outer diameter of rubber present. Somewhere along this thread, Sam mentions that the performance differences between the 4th Gen 1le and non-1le bushings and/or mounts was really due to the 1LE's "lack of voids" between bushing sleeve and rubber (or in the case of tranny mount, no center hole), rather than the material, which IIRC he mentions is actaully the same.

Design difference can include material durometer difference as well. Bear in mind that the synthetic rubbers being used can be designed specifically with different molarities within their mixtures or even their compounds, but I think really what you meant by "design difference" was the shape of the bushing.

Just wanted to clarify.

99HOSS

... "meant by "design difference" was the shape of the bushing" - exactly. When these cars are put under that much duress, in the end they're all still rubber bushings.

... and I always try to stay objective in these threads, as it is so easy to take things out of context.

Have you viewed the video I have posted taken from the Grand East circuit at VIR? It's been passed over in another section, so here's the links.
One lap video (TURN DOWN YOUR SPEAKERS FIRST)

Here's a short video involving a GT3 German auto.

It shows how well these cars can handle when setup well.
This particular Z28 has the 'Movit' brake kit, consisting of Porsche 996 front brakes, Koni's on all four corners with Ground Control ride height adjusters, a Sphon torque arm attached to the tunnel with a built in driveshaft loop, long tube headers, no cats, a Borla with no plates and a few other minor mods. I believe when we had it dyno tuned last year it had about 350 hp to the rear wheels. It still weights in at about 3300 lbs with a gutted car and a full rollcage.

Foxxtron

iTrader: (1)

Snap, that's you!

I was wondering for a bit when I saw what cars you had and where you're located.

Another frrax member saves the day. Thanks for working with me, and once again hope that nothing I wrote came off slanted.

99HOSS

... naw, we're kool. I'm just trying to help. I have two different names that I go by on the boards. This one and the one on the FRRAX board.

Have a good one, I'm off on business travel for the next couple of days, then I hope to make Summit Pt for a week-end at the track.

NyanaDream

Sorry to stray somewhat off topic but, are there any links or faqs on the f-body suspension design from factory?

slim0035

iTrader: (2)

One of the questions above almost touched on a concern I had. I am looking into an adjustable PHR and just want to know how the one you made helps to deal with re-aligning the rear end on a lowered car. I have DMS lowering springs for what its worth. Thank you for the awesome write-up. Nothing better than saying you have a custom rear suspension set-up you built.

Foxxtron

iTrader: (1)

Here's an accurate FAQ on the rear trailing arms and PHB.

http://www.geocities.com/motorcity/1...rethane%20good

JasonWW

iTrader: (2)

That's pretty simple. The rod ends are threaded into the ends of the bar. One end has left hand threads, the other has right hand threads. So the rod ends have to be ordered with the correct direction in mind. Anyway, by loosening the jam nuts and rotating the bar you will either pull the rod ends into or out of the tube. So the overall tube length will increase or decrease and that is what changes the rear axle location side to side.
Understand that?

slim0035

iTrader: (2)

Yeah, after doing more research and looking at the different syles of adjustable bars I figured it out. Thanks for the clarification.

leadfoot4

iTrader: (1)

Just to add my $0.02 worth to this discussion...

Prior to having a '96 Z-28, I had an '85 Firebird SE. At one point, I had poly bushings in the LCAs of the '85. Naturally, I removed the OE bushings, which were the same as pictured here, referred to as "1LEs". The Moog replacements are also the same as the "solid" bushings, vs. the "fluted" 4th gen bushings.

BrianMSmith

The solid rear axle has some limitations, but I am dumbfounded by how good my car is on canyon twisties with bilstein HD's valved for eibach sport lines, subframe connectors, stock control arms lowered to level, and the adjustable pan rod. Stock sway bars on the 01 SS model.

It still jumps around on bumpy corners, but the ride is good. It oversteers very controllably, never understeers (as long as the tires are hot and pavement is dry).

If you want a car that handles rough corners to perfection, get a 911. IMHO I think it's dumb to spend that much money on a car when a stinkin 5 year old Fbod can be this good!

mikex70

iTrader: (4)

Where is the best place to buy all the gear?? been looking around just wanna know where every 1 else is shopping.....

thanks