VILeninDM

hey guys,

I am planning to buy spohn front/rear coil over kits and need some help figuring out what I should get. Apparently they can get just about any spring rate you want, so now I am confused.

I am building the car for handling with occasional street use 1-3 days a week. My primary goal is to take this thing road racing. Will not see much drag strip, possibly only for tuning.

I haven't spoken with spohn yet, but I wanted to see if anyone has any input.

Also it looks like you have to provide your own struts while rears already have QA1 shocks. What do you guys think about Koni yellows? I just found out one of my bro-in-law brothers get's Koni's for half price.

RTFC

I would go 350's with Koni yellow struts up front. The extra compression force of the yellows will stiff the ride and increase the bump rate. A detuned compression strut (custom valving), I would then recommend either a 375 or even a 400.

Do not go with QA1's on the rear for road racing or handling in general. If you have a deal on Koni's, then go with some higher end double adjustable Koni Coilovers like an 8612

VILeninDM

Hey Dean, I was hoping you would respond.

Can you elaborate on the fronts a little? If I go with Koni yellows, 300 would be good. What's a detuned comp. strut? And if I go with one of these, I'd need 375?

QA1's for the rears is what Spohn is selling with the coil overs, I wasn't sure if I had any other choice. How important is it to have double adjustability? I was hoping single adjustment would do, but at the same time if I am investing this much already, I might as well get the double, if it really makes a difference.

I know double adjustable help a lot for drag racing to keep rear down at launch, but I wasn't sure I would need them for road racing.

I am planning to call Spohn sometime soon, I'll ask if it is possible not to include the rear shocks so I could put my own.

83 Crossfire TA

iTrader: (2)

(some mod can delete this if they want)

VILeninDM

didn't realize this post was offending

In case mods chose not to delete it...

I spoke with Steve today and he recommended 350 springs upfront and 175-200 (I went with 200) for the rears.

He also said he is working with Koni right now so they could release a shock that would work with his coil-overs. Apparently they are not making shocks that would fit Spohn design today. In the future he will give us options to go with different shocks for rears.

83 Crossfire TA

iTrader: (2)

No… no problem… I was thinking one thing and doing another and ended up posting something here that I intended to make a new thread… and since I can’t just outright delete the post I was forced to edit it so it had no content (and I’d be happier if a mod just deleted it) sorry

VILeninDM

jk, kinda figured that (been there myself a few times ), but it was weird because usually it says you've edited the post afterwards, but this one didn't

RTFC

Basically what I mean is just a strut with the same rebound adjustment range that Koni Yellows have but a set compression rate of more like a Koni red (or better yet a strut that has double adjusters for both compression and rebound rather than just rebound.

When Koni makes an over-the-counter perfomance strut, their main intentions is that the strut will be match to a factory performance spring rate like a WS6 spring. That added conpression rate will make a WS6 spring feel much stiffer reducing the rate of dive on the nose under hard cornering and or braking. It adds in essence rate to the spring coil. It you go with a higher rate spring, then the compression force can become too much and a reduction can be in line. A company like GroundControl can custom valve a shock or strut for your liking (if you are very patient- I hear GC takes forever) I actually have this problem on my car with too much compression rate with my heavy front springs.

I like a higher rate spring with a lower compression rate Strut rather than a lower rate spring with a higher rate ompression because the heavier spring will reduce overall travel in steady state through a corner. The lighter spring will comtnue to compress further and ground out easier at steadystate then bump encountered (I am talikng a very low car of course)

Steve mentioned in an E-mail to me that he wanted to try and have a few different options availiable based on price range and quality desired. Koni was one of the vendors he was looking towards to supply him with a top scale RoadRace shock for the rear coilover.

From what I know about the qa1's, they are very good for drag race and are valved acordingly. But the trouble lyes with the one **** adjustment I "think" dials both compression and rebound at increasing rate together. Someone more familiar with them please correct me if I am wrong.

On a double adjustable shock, basically the front compression and rear rebound setting control corner entry, and the front rebound and rear compression control corner exit- this gets much more technical, but thats a basic rule of thumb.
Actually heres a good link on Koni's site that explains a little more detailed. Just know that too much rebound will cause a car to "jack down" and repetitive bumps because the spring can not reextend after the first bump fast enough- consecutive bumps jacks it down worse and it will gound out. Also too much rebound will cause the tires to skip over bumps under hard braking and loose contact with the ground.

http://www.koni.com/_cars/frame.html

RTFC

I want to also explain WHY it is inportant to have an upper end or "good" roadrace shock. This is the main reason why KYB's high end adjustables just don't compare to a Koni.

The KYB may be just a stiff (for sake of this arguement, lets say they are equal in compression and rebound rates to a Koni Yellow, Which they in reality are not, but lets pretend)

The Koni's valving is much more percise, hence why they cost so much more. What does this mean? Shocks experience both low speed AND high speed dampering forces. The KYB may react just a strong to damper the high speed valving but will have a freer "Bobble zone" at low speed valving. This means when you simply press on you fender of your car in the driveway, the loni will damper better with the slight 1/4" up and down motion you give the fender where the KYB will slop more to about 1/2" before it dampers the low speed forces

Its those low speed damper forces that are very crucial at speed and gives you the One-with-the-chassis feel at high driving speeds A good roadrace shock mimizes that little bobble experience that the cheaper shocks will render because the valving is much more percise and snug. Its just better quality and that costs $$$. Hence why Penske 4ways are about $1600 each When I talk high speed and low speed, its the speed of the shock compression, not the speed of the car. You can have high speed compression hitting a severe bump at 5mph. Penske 4 ways have high speed compression and rebound adjustment as wll as low speed compression and rebound adjustments. A koni yellow basically only has equivilant to a high speed rebound adjustment and thats it.

VILeninDM

And this is why I was waiting for your response.

You are getting a little (by at least a mile) ahead of me on this stuff, but I always learn a lot from your posts.

I am still considering the never-ending cash factor. I've been scraping for the last 8 months so that now I could buy spohn suspension and some 275/40-17's. Steve mentioned that Koni makes double adjustable shock that costs $700/ea., but even with my deal, I doubt I'll be getting that now.

What you said about entry/exit and low/high speed travel makes perfect sense. I figure for now, I should be able to get Koni Yellows for fronts with QA1's for rears (the only thing Steve sells now) and later when the car is on the road and I can still afford gas and my a$$ is trained to fill the difference in different shocks, I'll probably upgrade to two way adjustable all the way around.

Thanks Dean