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Discussion Starter · #1 ·
My current setup:

Hotchkiss springs, bilstein shocks, spohn adjustable swaybar endlinks, BMR front and rear swaybars, BMR fixed extended length control arms upper and lower, spring perch relocated on axle adding like half an inch of ride height to the rear.

The car feels fairly planted street driving and what not, but when I took it to the course I was being thrown left and right with the roll. So it seems like the suggested advice is to go with a non-progressive spring which would be the global west 750#s.

But I've seen many mentions that if people could re-do it they would go with 800#+. I guess my question is where would I buy springs like that.

Then there's the question of ride height, what is the ideal ride height for these cars front and rear. Right now my current ride height is 27" inch rear and around 26" front. If I get the new springs for the front should I be aiming for 27"?

As for the rears, is keeping the progressive Hotchkiss rear springs ok?


Orrr do I just wait and save up for an adjustable setup.
 

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Discussion Starter · #2 · (Edited)
Moog 7590, on the forum thread listed at 880# the 780 is out of stock. Wonder if that even fits and how much it needs to be trimmed. I guess the main factor is the ride going to be all screwed up with the Hotchkiss rears since they aren't matched at all.

And i know the topic of roll center/corner balancing will come up. But with the stock suspension and full interior weight as far as I know my only adjustability is ride height right? So shouldn't there be an ideal ride height spec based on a stock car that would satisfy the ideal roll center and corner weights that I should be aiming for.
 

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1996 Impala SS
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In my opinion if you want to Autocross, I would go with a coilover conversion kit like QA1, with their tubular control arms, the OEM stamp steel Control arms have a lot of flex, also with coilovers you can adjust the rebound, compression and set it up to your liking. It’s pricey.. I’ve heard nothing but good things about coilover conversion’s on these heavy cars.
 

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I'd consider a full custom spring perch and then bag just the rear end for ultimate adjustability with the heavy duty front spring. Although I only have experience with the perch part of this thought experiment.

-Brian
 
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Not a huge fan of mixing components. Front springs from one mfg. Rear springs from another ,and sway bars from a third mfg. The odd of one assembling a combo more effective ,yielding better results than sticking with one vendor whose products were designed to work together are extremely slim.
 

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Discussion Starter · #6 · (Edited)
Not a huge fan of mixing components. Front springs from one mfg. Rear springs from another ,and sway bars from a third mfg. The odd of one assembling a combo more effective ,yielding better results than sticking with one vendor whose products were designed to work together are extremely slim.
If the advice is run a linear spring for auto x what would the matching combo be?

Just doesn't seem like there's any options other than just different part numbers.

The only springs with matching front and rear springs are all progressive rate springs.

Currently running hotchkis with bilsteins.

It seems like Ed , terry, Brian Coleman, Michael kazmar all run a similar combo. 750# or higher front linear rate spring, then stock SS or similar spring in the rear.

But considering you probably know all of them very well maybe you can shed some light on their setups
 

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Discussion Starter · #8 ·
Tbh I just started it for the first time. This car has been swapped with a t56 and 4.10s so it's not as family friendly as it was stock.

I guess the stem of this problem for me is that I'm not even happy with the hotchkis on the streets, so I kinda feel like I'm losing out on both worlds. Maybe it's cause the car is too low and throwing a spacer might be the saving grace, idk. I just need to go into other Impala's at this point with different setups to know what I'm looking for.

Well regardless I have an auto X session tomorrow, this time I'll have my seatbelt tightened properly 😁
 

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Easier to auto-x a car set up for the street.
That trying to drive a car on the street that was set up for auto-x.
Tires make a huge difference. I like Continental "Extreme Contact" for both.
Not for use below 40 degrees. So ,a set of winter snow/ice tires needed for year round operation.
 
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Stock size was awful. Couldn't get them off my car fast enough.
 
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Didn't some of the P71s have pretty stiff springs? I might be lying.
 

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Discussion Starter · #13 ·
Well the part numbers are all there for the moog springs. Specifically the 80098.

Front:
80098 … 4.000 … 0.781 … 748 … 1888 … 11.27 … 13.72 … SQ,TG - the one i would go with
81464 … 4.020 … 0.812 … 773 … 2713 … 10.00 … 13.51 … SQ,TG …
80860 … 3.995 … 0.812 … 780 … 3304 … 10.00 … 14.24 … SQ,TG …
7590 …… 3.993 … 0.828 … 880 … 3621 … 10.00 … 14.12 … SQ,TG …

Then go with a linear rate rear spring around the 150 range to match the stock rear SS spring.

However ride height would be a question, adjusting the front ride height seems straight forward with cutting coils, however if the rear sits high, based on how the rear coil is shaped I don't think you can go chop coils without repercussion.

I'd be willing to try it but then I read statements like this (forgot which thread I pulled it from)

"The "Sport Bilstein" combo of 1104 front/0929 rear does not provide enough dampening that is needed for the stiff 707 LBS spring. They were designed for the stock 440 LBS front springs. Mark Savitske of SC&C has a new set of shocks especially valved for B-Bodies by VariShock that should be able to handle the extra stiffness."

So if it requires me changing the shocks also then it's not a road I want to go down since I recently only changed to the hotchkis setup.


That being said, I wonder if it's the hotchkis bilstein combo that I'm not happy with, maybe a different shock with more dampening is what I'm looking for.

Watch and listen very carefully, this is me driving around the neighborhood, just listen to every time I hit a bump. I might've had stuff in the cubby adding to the noise but a lot of it is from the car.

 

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Didn't some of the P71s have pretty stiff springs?
P71 front spring coils rate @ 700 lb per in.
P71 rear spring coils rate @ 160lbs/in.
 
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Discussion Starter · #15 ·
Well the autocross session felt so much better today now that I had my seat belt tightened up 😁. Wasn't dead last and actually 2 seconds away from my brother in his 2021 STI, to be fair we are both newbs and someone skilled in the STI would be a good 10 seconds quicker.

Just working on driver mod for now till I can start justifying changes.
 

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My current setup for Autocross:
MOOG 7268 front springs #748
Speedway motors TrueCoil rear #200
Stock front and rear anti-sway bars. Stock front and rear suspension.
QA-1 adjustable shocks.

Waiting to be installed:
Globalwest two way adjustable rear trailing arms. upper and lower.
Globalwest front upper a-arms
Herb Adams from anti-sway bar. The stock bar seems to work rather well.

Biggest bang for the buck: Tires. The widest and stickiest tires you can afford. I run a set of 305/660/18 Pirelli Slicks on some 18x9.5 Corvette Wagon Wheels. I am looking to upgrade to some 315 tires on all four corners.
Next is driver mod.
 
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Discussion Starter · #17 ·
Nice!

I'm just going for an OEM+ build which means:

As stock interior as possible, so this means those big couches stay
As stock exterior as possible, essentially can't change out the wheels

So that limits me to like 270/40/17s but that won't be happening till these 255 nittos are used up.


Within my limitations just trying to find the combo that can rotate my car nicely.

From what it seems like most do is:
750 + springs in the front + a shock with valving that matches the spring
Keep the rear similar to the stock SS rear spring rate as possible and go small with the rear bar.

Which is not too far off from what your setup currently is madamorr. It maybe the way I think I'll be at least experimenting with.

 
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