Dbltime

After having two days of "new" handling issues with my car I found the answer. The amount of pressure you carry in your shocks depends on the temperature of the system at the time you check it. Just like tire pressure. I went out on 100# and came in on 150# of pressure on the loaded corner shocks. Filling them to 150# cold (as I did) is equal to filling your Hoosiers to 40# cold. Fortunately I figured this out before the race.

Greg Fishman

How did your other shock adjustments go? And most importantly, how did your race go.

FWIW I usually run about 150# in front and 180# in the back.

Dbltime

The event was a blast. C was a small field of 3 cars by race time. I was first in C but the 964 cup cars were killing me. 5 D cups qualified ahead of me. I got by one at the start, he re passed me in the second lap and I got by him again around lap 13 to stay. The next 964 was Steve Berlack #8 who was 20 seconds ahead of me at lap 8. By lap 19 he was 4 seconds ahead. At lap 21 the checker he finished 1.3 seconds ahead. Funny thing was the C & D cars were sent to the scales after the finish. I mentioned to Steve that I was reeling him in and he had no idea I was there. Jeff Burger, Robert Scotto & John Brown were 1,2,3 in D with Jeff turning a 1:23:0.

Interesting that a week ago I turned 1:23:5 with my car at 2625#. I came off the track yesterday at 2834# and my fastest lap was 1:23:7. So the obsession with weight is a bunch of crap at this level. Don't lift.

Andy McNeil GTP1 had the group one pole turning 1:14ish with a Champion GT1R close behind. The Champion car got around Andy someplace. I was watching from the carousel and they stayed about 2 to 4 seconds apart lap after lap. The GT1R won. The GTC3's looked like a slugfest. Not sure of the results.

Keith Peare had our group pole in his GT4R. Coming out of turn 10 for the finish he blew his gear box and drifted across for the win.

Plenty of great stories and bad luck stories as with all races.

Sorry to see such an exodus from C. Everyone cannot race a 996 Cup car.

Dwayne Moses won G #65
Ivan Arzola won H #201
Greg Merril waon F #13
Harry Kintzi won E #67

MJR911

Bill, You have to weight over 2800 in your class? I assume you're running as a 993 RS and I do not know the weights offhand, but that seems heavy! Great job on the win.

Cheers,
Mitch

Dbltime

993RS or CS needs to be 2794 coming off the track. I tried to stay dangerously close to that but now realize 50# does not really matter. I would prefer to be over than DQ'ed.

Bill - Chicago

Bill - was your wheel hop problem solved my dropping your shock pressure? If so how much did you bleed out? I have been fighting wheel hop in 993 with double adjustable shocks forever. There always seems to be a few place at each track I drive where it happens. My 996 with doubles did the same thing BTW. I run 200 psi. I did not think they changes pressure much on track given they are nitrogen filled. Also JRZ recommends 150 - 300 psi.

Dbltime

My car has a pretty awesome hand built suspension by Ivan don't lift Arzola at IMA. My car has always had impressive grip. I checked my damper pressures, cold, off the ground. They were all below 100# and none the same. I added Nitrogen to 150# all around. The car would hop and 4 wheel drift on high speed exits. The car was acting crazy. I tried all kinds of adjustments and tire pressure and finally was told to reduce all 4 to 100#. Went back on the track and my old grip was 90% back. Checked the shock pressures hot after the session and the two loaded wheels were back at 150 hot. Reduced them back to 85#. One hour later I was racing and out driving cars that were killing me in qualifying. The Nitrogen will expand. Apparently it is not that pure. I also filled/emptied and filled again my tires with Nitrogen but in the end had to start with the same cold pressures I always use with regular air. Maybe I am buying cheap Nitrogen? Anyway soften the suspension as many cars were doing and drop your times.

Bill - Chicago

If it is only hopping in one place or two, I usally adjust the line or my foot at bit. If it is hopping all over the place then I drop the compression, and increase the rebound to compensate for the increased body roll. Seems to help, but I usally don't have enough time in a weekend to get it perfect.

I have not noticed a softer car equals fast laps for me.

Dbltime

The softer set up is specific to Summit Point track. Thats why we need to keep logs on what works at what tracks and change the set ups.

Bill - Chicago

Gotcha, blackhhawk a local track to chicago is an example of a track I run a soft setup. I also keep a log. It is very helpful when you run a lot of the same tracks at around the same time each year.

Ed Newman

Summit was alot stiffer setup than what I run at Limerock! I think I should go back to the street springs and shocks for there!

A log is critical with an adjustable suspension.

Chris Martin

Bill, I was working in turn 1 this weekend. I always watched your car closely through 1, it seemed like you had your hands full in there. I was watching you chase the car in front of you, very fun to watch!

viperbob

Greg,

I was told by Moton to start at 150 fr / 225 rear. Does this seem high?

Thanks

ngoldrich

FWIW - In my 1989 E-stock turbo 944 with JRZ -

185 psi nitrogen - front
175 psi nitrogen - rear

Ambient temps seems to really affect my pressures too which I thought was strange using Nitrogen....

Norm

Greg Fishman

Bob,
My answer is to throw a question back at you. How does your car's handling and balance feel? I don't think there is any right or wrong answer and you just have to figure out what works for your driving style and car. I am sure Moton gave you a good place to start and you can tune it from there. Friend of mine has Moton's on his 993 C4S and I bet he is within 25lbs of that suggestion. In my car I would be afraid to use a higher pressure as my car borders on too much oversteer and making it stiffer (relative to the front) might not be a good idea.