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924RACR · Posted: Wed Feb 26, 2003 11:40 pm Post subject: Bilstein update and others

Just the latest and greatest update on the status of my efforts to get Bilstein race shocks under my car.

I had my front DP struts rebuilt by Bilstein; while they were in the shop, I had them compare them to the V36-series VW A1-chassis rally strut (V36-0059). They confirmed that this strut would fit. So if any of you want to use this strut, you'd need to buy them (around $200 each), have them revalved for your application ($55 each), and decide how to do the spring perch. The V36-0059 is set up to use a stock (5"?) spring size; if you're using stock springs I'd expect them to match up. If you're using the smaller 2.5" race springs (as I am), you'd need to fit adjustable spring seat sleeves to them, just as if they were stock struts.

To clarify, the V36 is a complete strut, not an insert, so replaces the stock strut entirely.

For valving, it comes with 270/100, which is a bit softer than I had recommended to me for my setup - 400/125. However, I'm running 400# springs up front, so with a more stock spring rate, you may be able to use them as is to keep costs down. Best results though will be to call up Bilstein, describe your setup (spring rates/torsion bars) and ask for their recommendations.

Of course these are not adjustable like the Konis. However, you can get user-revalveable tube shocks for the rear, which can be revalved (as expected), but also adjusted at the track by way of adjusting the pressure on the nitrogen charge. My Bilstein dealer (who races ITB Volvos) said that on a rear-drive car, the rear shock adjustment is huge, most important "knob" on the car, and a change of 15 psi in the gas charge can make more difference than a 50lb spring change up front! So, if you're concerned about adjustability at the track, that might help. BTW, I was quoted about $150 each for the rears.

As for myself, I have yet to put them on the car or drive it; still have the rears on order, and have spring seat issues to sort out of my own on the front struts (adjustment threads are seized). So I can't compare the Bilstein monotubes to the Konis. However every racer I have spoken to has said that, given cost not an issue, go for the monotubes over the twin-tubes anyday (Konis are twin-tube). Monotubes, you should note, ARE what the pros use, like Penske shocks, etc.

Other status update to the racecar... well, looks like this will be yet another year where I do not get the motor done. While I do have the pistons, I face probably another $1k worth of machining and parts needed to get the motor in. Since I want to do other things than just race this summer, and may be facing the purchase of a set of tires, I'm going to hold off on doing the motor for now and just continue to play with the suspension. I think I'll probably pick up the rear spherical bushings (Racer's Edge) too, in the meantime.

I have my lexan hatch, though not assembled, and the fiberglass hood is on the way from 944Racing.com (though I don't yet know which car these will be put on - depends on many other things).

Cheers,
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

jjadczak · Joined: 03 Jan 2003 Posts: 346 Location: Accokeek, MD

Well my project for the front end is on hold for a while too so I feel your pain as well. I had to buy a kirkey seat and replace our plastic one, and of course the seat brace and mounting brackets have to come too. In addition, I forgot to factor in a new transponder purchase before we can go to school or get the cars annual tech this weekend. I think my race supplier is going to name his next boat "Jeremy" after it's benefactor!

Jeremy

lordam · Joined: 31 Dec 2002 Posts: 45 Location: New South Wales

Vaughan
I am confused as to when you think the front Bilstein inserts should be put aside and these Bilstein mono-tube struts should be used.

You suggest that they need revalving because you use 400# springs. Is it not possible to revalve the inserts?

If a competition set up was being used with 250# front springs, what is the best Bistein option?

John
931 82 Red (on stands)

924RACR · Posted: Mon Mar 10, 2003 1:33 am Post subject:

No, the inserts are not revalvable. I'd recommend you ask Bilstein Motorsport for a valving recommendation for your specific setup - though the stock inserts might be Ok to deal with still such a soft spring.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype