Chevy Impala SS Forum banner

1 - 20 of 22 Posts

·
Registered
Joined
·
6,129 Posts
Discussion Starter #1 (Edited)
Hey Guys, I know it's been a while...

So I picked up a 9C1 that I plan to AutoX with next summer and am looking for the most tried and true setup you've managed to put together. It will be a daily on the street, too, on street tires. I will swap over to dedicated race tires for the track though.

This will be a mostly stock motored, T56'd, 4.10'd machine.

So, whatchoo got? Springs, sways, bushings, alignment... I want it all! :D

I will be posting in the wheel & tire section for recommendations there.

TIA!
 

·
Registered
Joined
·
534 Posts
Nice to hear from you again.
My favorite current T-56 set up.....Eibach Pro Kit #3832.140 (discontinued but someone might have a set still new) or 3837.140. (Don't try them without a shock with a lot of rebound control). Stiffer springs on N.E. roads will be less than ideal, rough tracks ditto. Koni #8040-1087 and #8040-1088. Start with Adjusting fronts to full hard and rears to half way. Adjust every weekend. ZQ8's OEM#-15956547 and Airlift #60733 start at 7psi drivers side, 12 psi pass side. Adjust every weekend. 4.56's will require a high speed balanced aluminum or carbon fiber drive shaft (low gear , high rpm + vibration = less than ideal). Hellwig #55720 1 3/8" hollow front sway bar, Hotchkis # 2205 1 3/8" hollow rear sway bar, (ignore claims that same diameter and construction sways F+R will cause oversteer with these springs) DMR rear frame Braces # 5029-W. Umi adjustable rear upper control arms because getting pinion angle perfect matters ( they require the DMR to keep from binding) , Umi fixed rear lower control arms #3615-r, Borgeson stainless steering shaft (collapsable), #450024, upper u joint #015252, lower u joint #034931, AGR 12:1 steering box #225153 ( requires a dedicated Pitman Arm). Box the frame and seam weld it, install braces between the end points of the front and read frame. ( I've posted the easiest way to make the frame rigid many times in the past. The suspension having a rigid leverage base benefits greatly and removing the spring rate from the frame makes for the most precise vehicle possible that still has a oem B-body frame).
 

·
Registered
Joined
·
6,129 Posts
Discussion Starter #3
Wow Scot. :eek: Thanks. :)

Drives pretty neutral with those Eibachs?

I was thinking more along the lines of those MOOG 5662 in front and some undetermined rear spring. I was also thinking of going with a Panther rear bar (Maruader/Crown Vic) and 2nd Gen Fbody front bar to start with.

I didn't realize that anyone made a carbon fiber driveshaft? I've been out of the game for a while, I guess. I was thinking about using an SSR aluminum driveshaft, if I could find one. I think they are like 4" or 4.5" or so. Maybe even 5"?

What do you have for brakes? I have a C5 13" front conversion setup that I was going to install in the wagon, but that may go to the caprice now...

Thanks!
 

·
Registered
Joined
·
534 Posts
Springs 101
ANY time you use different springs F+R you inevitably create a mismatch in the bounce frequency of the car, which makes for a clumsy totality. Plenty do it and swear by it, but it is not optimal. For a demonstration, take all the shocks out of the car and bounce the car at both ends. Mismatched springs will bounce at a different rate and settle at a different rate. Nothing good can come of this in a moving car and shocks can't fix it. Spring sets have many constraints and this is one of the most important. Always use all 4 springs from sets manufactured to be used together.

The F-body F bar is also a clumsy application. The end links are misplaced, and it doesn't add enough roll resistance; for better, see previous response.
Ditto for Crown Vic. It mounts differently than the B-body but still can't provide enough roll resistance.
With stiff enough springs the FE1 front 1 1/16 and FE3 rear 1 1/16 work better than the F-body/CV.

Any driveshaft spun to be balanced at 10,000 rpm will work great. Any less is not optimal.

Brakes are Brembo's, F+R Outstanding. One car with C-5, another C-6. Outstanding.
 

·
Registered
Joined
·
534 Posts
Procedure for reinforcing the front frame rails. Remove the front sway bar. Use a piece of steel one inch thick, as wide as the frame rails, long enough to be welded across the attachment points where the sway bay used to mount. Drill it to mount the front sway bar one inch lower than it used to be. Use slightly shorter end links to keep the bar OEM level.
The car feels much more solid, steering response is very noticeably faster, fewer sqeeks/rattles and the ride improves. All positive changes and no negative one's. Takes an hour, cost next to nothing, I've now done it on all of my B-bodies, is especially noticeable on the 1 1/2 inch solid front bar. Without this, anything larger than a 1 3/16 solid bar is bending the front frame rails, wasting the potential benefit of the larger bar.


I've boxed the frame of every B body I've owned. This does add some weight, but does far more long term good for that weight. In addition to the front brace that changes the sway bar mounting attachments there are two other similarly very low weight/large gain things worth doing.
At the ends of the rear frame rails. Take a 40" piece of 1 1/2 stainless exhaust pipe, put a small bend in the middle to clear the fill pipe, weld on one side at the wide spot at the end of the frame rail, wedge the other side(with a big hammer) into place and weld. Now the frame rails are rigid at the back, similar to the effect of the brace welded to the front. The "Buick Brace" just bolts on, is flimsy anyway, and doesn't accomplish 1/100 what this does. Then add a set of DMR#5029-w rear frame braces. Total weight gain, less than three pounds, very noticable improvement even with a previously boxed frame.
I've posted ALL of this previously, with pictures.
Do all four of these additions and the perception of solidity, improved steering feel and faster steering response, improved roll control and reduced pinion angle shift change the whole car for the better. Even with boxing the frame, everything adds less than 50 pounds.
 

·
Registered
Joined
·
6,129 Posts
Discussion Starter #6
Well, I did get myself a new welder and that seems like a pretty good way to learn how to use it. Nobody'll see those welds anyways! ;)

Got those pics handy? Or links to the posts where you do? The search here is not so good... ;)

Oh, and don't the Eibach's have an issue with the rear springs sagging after about a year?

Thanks for the help and the tips. :)
 

·
Registered
Joined
·
534 Posts
The search here is no better. Most of my picture posts predate the crash.

I did a few pictures on my cell phone recently. PM me your cell # and I'll send them to you later today.

"Oh, and don't the Eibach's have an issue with the rear springs sagging after about a year?"

I've used more than a dozen sets and never had an issue. Fact is, any new after market spring used with a worn or inappropriate shock will sag. Rebound control (lots of it) are what b-body shocks need to have the most of or the spring will be under dampened and suffer.
 

·
Registered
Joined
·
6,129 Posts
Discussion Starter #8
This is great info. Thanks Scot! YGPM! :D
 

·
Registered
Joined
·
58 Posts
i'd be interested in pictures of the re-inforcements also!
 

·
Premium Member
Joined
·
984 Posts
scot,

I noticed you referenced the Hellwig hollow sway bar instead of the solid one. I know it's slightly larger than the solid but my mental battle was trying to figure out is the angle of twist really going to be reduced when using a larger bar when it's hollowed out like that? If not, I don't see much benefit in saving a few pounds on a 4000+ pound car.

One thing I didn't see was the panhard rod, which I've heard very good things about. Albeit custom, it's supposedly worth the effort.
 

·
Registered
Joined
·
534 Posts
Hollow VS solid is not just about saving weight, though stuck out at the pendulum end of the frame it does matter. The wall thickness of the Hellwig hollow 1 3/8" bar gives it the same roll resistance as the now discontinued solid 1 5/16" bar. (because of wall thickness, the Hotchkis 1 7/16" hollow has less roll resistance than the Hellwig 1 3/8" hollow) So with the weight savings, and the same roll resistance and the fact that the solid 1 5/16" is discontinued, the hollow 1 3/8" is what works best and can be bought new. The 1 3/8" solid bars are all discontinued now, but were only effective on cars with boxed and seam welded frames anyway, that also had front frame rail crossmembers. To balance the B-body, they required a 1 3/8" solid rear sway bar. The only such bar ever made was from Quickor Suspensions, long since out of business, and that bar required poly mount boxed upper and lower rear control arms and DMR rear frame braces and the rear frame rail cross member. FE1 springs worked best with those sways, and with all of the above, 1 1/2" solid front (Quickor) and 1 1/2" solid rear sways worked well too. Overkill for most applications though. I eventually used those 1 1/2" solid bars on my boxed, seam welded, crossmembered and all of the above , 7200 pound 96 Fleetwood 48" stretch limo with the OEM coachbuilder springs, Airlifts, ZQ8's and Koni adjustables set at full hard, and 275/60-15's(no 17" have enough load rating for 7200 pounds) on "Limo only" OEM aluminum wheels. Fabulous result, dead flat handling and comfortable ride ( Wheelbase!!)...with one back seat deleted and the floor leveled with Styrofoam and a temperpedic pad...its my dog car.

"One thing I didn't see was the panhard rod, which I've heard very good things about. Albeit custom, it's supposedly worth the effort."


With cars modified as above, it's not worth the effort. I've tried it and can't tell a difference. It's still on one of my 94 Impala's but not worth removing either.

I emailed some pictures to toomanytoys
 

·
Premium Member
Joined
·
984 Posts
Thanks for the quick response. I had no idea that the hellwig solid's were discontinued. That might explain why Summit's price on them was actually more then the new tubular design. Please go into detail on what exactly the DMR braces do (if you have time, don't mean to sound pushy :D). I have a list of stuff that i'm planning on ordering and the braces have been on it for awhile, but it's further down so I hadn't done much research.

As far as the PHR goes, I was planning on doing this to completely eliminate slop in the axle. I want to go the whole "VIP stance" route, as well as performance. This means placing my sidewalls very close to the fender lip, and if it has any slop i fear that i'll be leaving little chunks of rubber all over the road. I'm no fan of listening to "rubstep" lol
 

·
Registered
Joined
·
534 Posts
Some previous posts....
Basically what they do is tie the forward mounting bolts of the upper and lower control arms together creating a triangle which is a stiffening brace between the frame rails and the upper attachment crossmenber for the entire rear suspension. The upper control arms and shocks bolt to this frame piece and the springs also ride on this frame piece. I could actually "FEEL" the difference in the car! I was surprised. Many of the other parts have been changed - This was over 160K miles ago! I would definitely do again.
Drag racer or not, with this style of a factory four link, when you accelerate, physics will tell you that the rear end is trying to roll the pinion up and the rear end right out the back of the car. The only thing stopping that is the upper control arms attached to a flexible crossmembers. Triangulating the cross member will help keep this from happening. Does it help strengthen the rest of the frame. It sure can’t hurt and it’s a truly bolt on deal. This doesn’t even get into the subject of pinion angle which can change up to 1 degrees with as little as 1/8” of flex on the cross member. So if you have your pinion angle set at 2 degrees you just lost 1/2 of it. The better the tires stick to the ground the more pinion angle can be lost. This will create inconsistency at the drag strip for sure. It will also create unpredictable changes on an autocross suspension.
.I've used Umi Adjustable rear upper control arms, standard and extended size, and Hotchkis Adjustable standards on four cars, three T-56 cars and one auto. Always under very hard transient turning, even at low (autocross) speeds, I've felt some bind or at least tension from the UCA's. On all four cars after installing rear frame braces from Dick Miller Racing #5029-w, all of that binding has been eliminated. It took driving a B-body with stock oem uppers to prove to myself that the cars with the poly bushing arms and the braces have no more constriction than the stock car. Cheap fix at $125.00
Dick Miller Racing Part # 5029w
1-662-223-2301
These braces triangulate the frame mounting points of the upper and lower rear control arms. They bolt onto both mounting points at the frame. The frame flex at those points can distort pinion angle over 1 degree, and add to the bind at the LCA. It's not an issue until the loads get pretty extreme, and they don't increase handling ability like G forces, so much as they as give a more solid platform for the suspension to work off of. The car gives the perception of being more precise.
Seam welding and boxing the frame adds even more of the same.
 

·
Registered
Joined
·
534 Posts
So much easier when you remove the body. After boxing, you have to cut access holes for the body bushings. Just 2 inch circles on the bottom of the frame so you can reach the body bushings from the bottom now that the side is boxed. Do the F+R frame end cross members at the same time and seam weld every inch you can. Then the suspension will have a rock solid foundation to leverage against.
 

·
Registered
Joined
·
110 Posts
What tires would you recommend with this set up on SS rims?
 

·
Registered
Joined
·
534 Posts
Almost 8 years later and there's no reason to change one word. At VIR road coarse the 96 Limo, sans the German Shepherd/Wolf Hybrids, could match the lap time of a C5 Corvette. The LT-1 Stroker has something to do with that in addition to the suspension/chassis work and yes I still have that car. Even in Zurich it's a rare one.
 
1 - 20 of 22 Posts
Top