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bilstein turbo cup shocks

hey guys I have an 86 951 and just bought the cup car shocks, ak1120,ak1121, and ak37354. Are these going to be a pain in the ass to install or are they pretty straight forward. Also any recomendations on springs. Thanks for the help.

Chris

What kind of driving will you be doing?
Are you keeping the rear torsion bars?
What kind of wheels? Sizes? Tires?
Alignment specs? :)

I have a set of those same shocks waiting to go into my car. Mine were revalved and came with springs to match. If I remember correctly I have 350# in front and 300# in the rear. The springs are Hypercoil in front and Eibach in the rear. Whre did you get your shocks and did they come with any spings?

I got my shocks from eshocks.com. They were the cheapest I could find. I have not bought springs yet but plan to go with the hypercoils with similar rates to yours. Do you know what size springs i would need. Also with those spring rates have you done anything to the torsion bar? Mine is stock so would the spring rates I would go with change in anyway?

I'm going to be running the stock torsion bar along with the helper springs in the rear. This setup with the revalved shocks and the spring rates were matched to my friend's 86 951 which would be running with the torsion bar in place. Since my 88 non-S 951 is basically the same, I'm not planning on changing anything. Did the shocks come with the spring perches? I think I am using the 2.5" diameter springs.

951 sickness what do you mean by helper springs? Does that refer to the coil over kit and if so were did you buy it? One other thing, your front springs how long are they?

Chris:

What is the valving for your new struts?

For example: if the valving is 300/120, that is compression/rebound.

Multiply 300 x 10 to get decameters, then divide by 4.48 to get the spring rate in psi that the shock is valved for. So, in this example, it would be valved for a 670# spring rate.

Bilstein will revalve/rebuild any of their struts/shocks for $50/each plus shipping.

Chris:

Oops, I cannot read my own notes. Sorry, disregard the previous math example. I completely screwed up the whole thing. It is rebound/compression.

The real story is add 1000 to compression, then divide by 4.48! This would give you a 250# spring.
I knew something did not look right.

Sorry for the confusion. I am trying to do too many things at one time.

Also keep in mind that those numbers are an average damping rating. Bilsteins use the deCarbon mechanism which changes damping based not just on shock velocity like most dampers, but is also position sensitive as well.

<blockquote>quote:<hr /> I'm going to be running the stock torsion bar along with the helper springs in the rear. This setup with the revalved shocks and the spring rates were matched to my friend's 86 951 which would be running with the torsion bar in place. Since my 88 non-S 951 is basically the same, I'm not planning on changing anything. <hr /></blockquote>You may not be planning on it, but you probably will have to change things. You'll most likely need to reindex your torsion bars to get the rear ride height right after you add the coilovers. Eight hours labor, minimum.

Russ Murphy, I notice that you have a turbosmart 45mm wastegate. Can you tell me were you purchased it and if you recommend it.

dagame27: Where on your front struts do you have the compression/rebound numbers? My struts are still assembled and I can't find them anywhere.

<blockquote>quote:<hr />You may not be planning on it, but you probably will have to change things. You'll most likely need to reindex your torsion bars to get the rear ride height right after you add the coilovers. Eight hours labor, minimum.
<hr /></blockquote>Yes, I know I might have to reindex the torsion bars but since his car dropped down only a little when the stock stuff was reinstalled and my car is dumped in the rear, I'm pretty sure I can get a good balance between ride height and a balanced suspension. If it coes to reindexing the torsion bars I would consider removing them all together and getting heavier springs for the rear.

White944Turbo: My front springs are 8" long and the rear shocks have springs and a threaded body. If I remember correctly my friend got the whole deal at Vision Motorsports.

You'll need to look under the dust boot. The numbers are near the top of the polished shock rod. May be real hard to see with the shock still on the car.
Alan

white944turbo,
I got it from TEC(turbo engineering corp). $337.00 I beleive. It's to early to tell as it's not working yet. The 1/8 pipe thread fitting into the upper housing is leaking (no teflon tape--DOH!) so I have no boost control other than my right foot. :) But it sure does hold boost (read- doesn't leak) better than my old stocker. I'll post about it when the exhaust/fuel leak/air leak is completed.

Thanks for the info. guys.

Im planning to change my shocks to on the car. The car has the Sachs shocks now :( but i want to replace them with Bilstein or Koni. I heard that the Bilstein is simply bolt on, on cars that had Sachs before. But if I want to replace them with Koni do I need to replace the whole package in front?

The springs will be replaced with H&R

The car is a 951 1991 not with M-030 package

I have all the answer I need now.

/J

Ok so with my bilstein cup shocks I am going to want to use approx 350# springs in the fronts with approx 300# springs in the rear. Would these change at all knowing if I am using the stock or a bigger torsion bar? Also I believe the spring size I need for an 86 951 is 2.5 ID but what is the length I will need? Thanks Guys

Chris

what are the stock spring rates, also what is too much for agressive street use? i heard weltmeister springs were the best for the 944 turbos any truth to that? i heard that 250 pound springs is the way to go, and it loweres ride height 1.5 inches in front, any info on this, and then about the rears, i heard you can only get 1/2 inch lower out of torsion bars from stock, is that true? So how low to go with stiffer springs and what do i do about the rears no able to go as low as the front now if i do this? thanks

An ideal 944 Turbo suspension setup will have the rear ride height slightly lower than the front [like Graham Gillies' car]. Another thing you want to keep mindful of is the WHEEL RATE that a spring will have at different locations on the car. Someone on this board had a spreadsheet of different suspension setups [about 30 of them] consisting of all different springs rates, and the front:rear WHEEL RATE differential [very useful info].

In another thread, someone described his experiences with all different WHEEL RATE differentials. A wheel rate 75% higher at the front was deemed good for the track [minimal understeer] and best for the street. Other setups like those used by Technodyne [?] had as low as a 50% front:rear WHEEL RATE differential, promoting more oversteer for an experienced driver. Going to equal wheel rates front/rear is said to provoke WAY too much oversteer for a track car...but probably wouldn't be noticed on the street.

I was considering going all-out with Bilstein coilovers and SUPER stiff springs...but after thinking about it for a long time it's not what I want. I don't need the height adjustability for a street car. I figure I'll get some sport shocks [Bilstein] and the 1" shorter Weltmeister springs at the front, then lower the ride height at the rear and have an alignment done. Then I can offset the slightly higher rate of a 1" shorter Weltmeister spring [200# Vs. ~140# stock] with a 968 m030 adjustable rear sway bar...front sway bar will remain stock. To see how spring rates compare to WHEEL RATES, refer to Paragon's Tech Session here:

<a href="http://64.226.197.185/Paragon/Info/944_tbar_rate_comparison.htm" target="_blank">http://64.226.197.185/Paragon/Info/944_tbar_rate_comparison.htm</a>

A general rule of thumb with the 944 Turbo is that front spring rates translate to ~90% wheel rate, rear torsion bar rates have about 100% wheel rate [great geometry, low weight], and rear coilovers have ~50-60% effective rate at the rear wheels [has me thinking they're really NOT meant to go there]...hope this helps.