Terry Adams

Here are the camber changes at the last alignment. Specs are in decimal fractions of a degree.

Front left before -0.8 after -0.2 Which one would cause more inside front tire wear?
Front right before -0.9 after -0.2
Rear left before -1.3 after - 1.0 No uneven tire wear at the rear, before or after.
Rear right before -1.4 after - 1.0

I have no idea if these are factory specs, but the shop will know. Does the 18" need less camber than 17" for the same result?

Viken

Terry,

You had a much better alignment setup before than after. The after figures look much too conservative to me. Factory specs are as follows:

Front camber: -20' ± 10'
Rear camber: -1°10' ± 15'

I would not hesitate to go for -30' in front and -1'30° at rear.

Terry Adams

Thanks Viken. I'll go with your recommendation, as it is just at the high end of the factory spec. I think my front inside wear was coming from the -0.8 and -0.9 camber. If there are still 60' to a degree, then your -30' would be only -0.5, more conservative than the -0.8

DJ

[quote]Originally posted by Viken:
<strong>Terry,

You had a much better alignment setup before than after. The after figures look much too conservative to me. Factory specs are as follows:

</strong><hr></blockquote>


I was thinking the same thing. Terry, if you got a little uneven wear on the insides of the front tires with those specs, it just means you spent too much time going straight, and not enough time going around corners.

Have fun, it will even out the wear.

os993

[quote]Originally posted by Viken:
<strong>...As to alignment, I have gone to RS specs. Those work great for aggressive driving. If you have any inner tire tread wear concerns, I suggest slightly less aggressive camber settings.</strong><hr></blockquote>

Viken, how will tire wear change with this setup? Also, I'm curious if RS specs are only better for track. I wonder how these specs would feel on a daily driver?

Lastly, I wonder how 17" would perform with an RS setup? Easier on tires, ie more rubber compressing, less tire wear??

Cheers!

Viken

[quote]Originally posted by oleg steciw:
<strong>Viken, how will tire wear change with this setup? Also, I'm curious if RS specs are only better for track. I wonder how these specs would feel on a daily driver?</strong><hr></blockquote>

RS alignment settings are OK if you are an aggressive driver on the street or track. If you spend too much time in a straight line, you will have some accelerated inner tread wear.

[quote]<strong>Lastly, I wonder how 17" would perform with an RS setup? Easier on tires, ie more rubber compressing, less tire wear??</strong><hr></blockquote>

The size of the tire will not matter in this case.

Viken

Last weekend, I drove my car for 300+ miles on mostly familiar roads. The Bilstein shocks are definitely firmer than the M030's by at least 10%. More like 15%-20%, I would guess. They do have a firm ride with more road feel. Their valving seems to be optimized for the 993's body structure quite well, however. A firmer shock might cause more body flex and noises. They also seem to be a good match to the ROW M030 springs. The overall damper performance is more sporting than stock making these a better choice for those who occasionally drive on the track. So far, the Bilstein HD/M030 combo is proving to be an even better compromise street/track setup than the M030/M030.

Regarding the height adjustment issue in front, I am told that the bottom black locking nut is not needed. If that nut is removed, one could lower the front another 1/4" or so. Apparently, it would be necessary to keep ultra stiff race springs from twisting the spring perch nut.

[edited part on]I just got off the phone with the shop that did the work and they do not recommend removing the black locking nut on the front shocks. Apparently, these shocks rotate and with enough pressure may cause the adjuster nut to move up or down on the threads. If the adjuster is set against the lowest thread, it might even come off.[edited part off]

cfdarch

Viken

I have been following your move to Bilstein HD. Curious whether you have read the May 2002 Panorama (Part 2 of a two part suspension study of 996). The team doing the testing included Mike Shatz. They tested the following dampers; standard usa, sport usa, ROW sport, and Bilstein HD's. Using Bilstein's Shock dyno they found the front Bilstein HD (#VN7-4612)significantly stiffer in compression and rebound. In the rear the Bilstein HD(#BE5-2993)was significantly less stiff in both compression & rebound than either USA or ROW sport. Also the rear Bilstein HD was was generally stiffer than the standard USA. I am not sure how these Bilstein HD part #'s compare to the one's you are using. Would stiffer dampers in front relative to rear tend to contribute to additional understeer as would be the case w/ stabilizer bars and springs? Did you have MFG.shock dyno info regarding the ROW 030 dampers you had before and the Bilstein HD's you have now? Would Gert Carneal have this info? Thanks in advance

Viken

Cary,

The article in Panorama was about factory 996 shocks made by Bilstein. I doubt that the results from those tests have any correlation with 993 shocks factory or otherwise.

Viken

Sorry, I didn't realize they had a small blurb about the aftermarket HD for the 996. They say the front is significantly stiffer while the rear is about the same as the US factory shock. I assure you that this is not the case with my HD's. All four of them are firmer than my previous M030 shocks.

cfdarch

Viken

Fair enough about the apples and orange thing however I just found Bilstein's approach?/results regarding the rear HD's compared w/ the fronts on the 996 peculiar.

The other part of my earlier post asked if you are aware of a source for or seen shock dyno test results for front and rear 993 ROW 030 dampers and the Bilstein HD?

I am considering the ROW upgrade and was
curious if there is any quanifiable data. You are in the situation of comparing your old ROW dampers VS. new Bilstein's. Your first response to your upgrade seemed tentative.

Thanks again

Viken

Cary,

Sorry, I don't know of any dyno figures for the 993 shocks. Personally, I didn't want an adjustable shock like the PSS-9 but I wanted something better than the Monroe's. For this, I went with the Bilstein HD's and I am, so far, happy with that decision. Remember too, that these shocks allow you the use of the adjustable anti-roll bars for some fine tuning.

KC993

Viken,

Can you share you swaybar sizes and whether you are going to do any changes?

Thanks...

Viken

[quote]Originally posted by KC993:
<strong>Can you share you swaybar sizes and whether you are going to do any changes?</strong><hr></blockquote>

I have 22 mm F and 20 mm R. I had decided to go with a 21 mm R but I am also doing some tire pressure testing to see if I can eliminate understeer.

cfdarch

Viken

Thanks for the info, I value your point of view and contribution to the board more than you could ever know. Your positve feedback is really all I need. I have e-mailed Gert to see if he has seen any info and if he has I will post it.

I just ran my first autoX yesterday w/ the local P-club and it was a hoot. What a great car! This experience just pushed me over the hump to replace the old continentals NOW and install the suspension components the car should have had in the 1st place.

Regards Cary