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Mercutio
08-01-2010, 10:30 PM
For the first time since blowing the engine autocrossing in December 2008, I took my SC back to an autocross event. The good news is that this time I was able to drive the car home. Not much else went right.

I had one decent run. The video: http://www.youtube.com/watch?v=YdLRcOoaB1k

It was extremely hot and the car definitely didn't like it. I boiled the PS fluid again, but at least I never lost power assist. Ultimately the engine got hot enough that I decided to call it quits after only 4 of 6 runs.

Since no one else was in my class, I actually moved up two classes to XP rather than race alone. XP is pretty close to anything goes, and it's an extremely fast class. XP cars are typically not street legal, run real slicks (not DOT-legal R compounds), are totally stripped, and have huge power. I finished fourth of four against this tougher competition. First in class was a very well built/driven 240SX. That car was way out of my league. Second was an E36 M3, and third was a 914-6.

Some conclusions:
-My front tires were 2 years old and the rears were 2.5 years old. There wasn't a ton of grip, but they weren't nearly as bad as I thought they would be. In all, the car handled much better than I thought it would. Either my driving is a lot better than it was 2 years ago, or the last 100 or so pounds off the car has helped quite a bit. Probably both. But...

-I had forgotten how slow the steering was on this car. After autocrossing other vehicles for the past year and a half, I was shocked at how much steering input it took to negotiate the slaloms. I was constantly behind in steering. Ultimately, slow steering is to me the car's biggest handling fault. A quicker rack for these cars would be a huge handling upgrade, at least for my purposes.

-If I can't race without boiling the PS fluid I can't autocross this car any more. I've got a huge cooler and I was using Royal Purple synthetic fluid, but that wasn't enough.

-That ebay aluminum radiator might not be enough for sustained heavy use in hot temperatures.

-The SC did have more speed in it. Had I not had problems, I think I MIGHT have at least put pressure on for second in class. Maybe.

-The UHMW rear LCA bushings are fantastic. I had no wheel hop at all and the handling at the rear was very predictable, especially on ancient, worn-out tires. You all need to order these.

-Oh, and I've got a bunch of CEL codes now. Should be fun.

Mike8675309
08-01-2010, 10:48 PM
A nice run... did you tape the camera to the roof of the car? i didn't find any trouble with my power steering, but the slaloms were only 3 cones at a time, and I do have to say, by the last cone I was starting to get behind, so I'd agree, a faster rack would be nice for auto cross.

Mercutio
08-01-2010, 10:57 PM
A nice run... did you tape the camera to the roof of the car?

It's a suction cup mount for a Chase Cam.

Kurt K
08-02-2010, 11:46 AM
-If I can't race without boiling the PS fluid I can't autocross this car any more. I've got a huge cooler and I was using Royal Purple synthetic fluid, but that wasn't enough.
What are the specs of your cooler? I've had some good luck with a small setrab fanpack cooler for my transmission. Actually, the small one didn't keep up with my small converter. Anyway, maybe it could be run in series with the cooler you already have. I was able to located it under the battery in the fender on my 92, but I don't think that side will work for you due to all of the brake stuff.

The double I have looks like this:
http://www.setrabusa.com/images/fanpack300x200.jpg.

ricardoa1
08-02-2010, 12:07 PM
Good stuff.
When my aligment was out of whack my car was very darty and steering inputs were very minimal for it to turn. You could try adjusting the caster so the car becomes more responsive to the steering inputs, you sacrifice returnability though so keep that in mind.

DLF
08-02-2010, 12:13 PM
The UHMW rear LCA bushings are fantastic. I had no wheel hop at all and the handling at the rear was very predictable, especially on ancient, worn-out tires. You all need to order these.


Delrin, not UHMW, for what it's worth. ;)

I'm glad that you're happy. :D

DrFishbone
08-02-2010, 12:32 PM
I've getting prepared for my first Autocross event on the 15th...any tips for a first-timer?

I've got a universal-fit 19x22 radiator from Jegs in my car...behind a decent-sized FMIC...I'm a little concerned with it's cooling capacity, but hopefulyl with some new air-directors and lowest temp fan settings it'll work out.

What thermostat do you have in your car? Fan settings altered?

S_Mazza
08-02-2010, 02:40 PM
Nice race! Your car looks fast, from the takeoff to the finish.


-If I can't race without boiling the PS fluid I can't autocross this car any more. I've got a huge cooler and I was using Royal Purple synthetic fluid, but that wasn't enough.

Can you do some kind of an ice tank around the PS cooler, or would that be banned by the rules?

Incidentally, I like the idea of an autocross, but I am not sure I like the idea of doing it in a parking lot with light poles and cart returns all over. It's not inconceivable to get loose and end up in one of those things.

Mercutio
08-02-2010, 05:59 PM
Kurt, I don't recall the specs on the cooler. It's a B&M transmission cooler but I don't remember the rating on it.

Rico, I haven't had the car aligned since early 08. I have no clue what its current alignment settings are, but since it's not twitchy I don't think there's much caster or toe in it.

DLF, my mistake--delrin it is. Everyone still needs to buy them.

Dr. Fishbone, I'm not certain on the fan settings. Dave D did all the tuning, but I can tell you the pusher fan is no longer there. As for tips for a rookie, pump up your tire pressure to at least 40 PSI (assuming you're on street tires). Smooth is fast, and it's better to give up a little time entering a corner and gain it coming out than going in too hot and suffering on corner exit.

S_Mazza, ice on course is a no-go. And if you go to an autocross put on my experienced racers they'll be smart enough to route the course around any potential obstacles. The SCCA has minimum distances we're required to keep from curbs, trees, etc. Odds are that any parking lot that SCCA races on will have very few potential things to hit. Go watch one if you're still not convinced, but I'm sure you and your car would be fine.

Mercutio
08-02-2010, 08:01 PM
Good news: the engine appears fine. Somehow the dial switch that selects which engine tune to use got moved from the standard setting to an unused position, so the car was trying to run on the factory tune. The CEL is gone and all appears to be well. I had no problems on a brief drive, and the temp stayed lower than yesterday as well.

Also, now that the IC tubes are cool, I was able to check the PS fluid. I expected it to be nearly empty, but it was nearly full. I may have had some fluid just sling out the fill tube due to cornering, but either way the pump was making a ton of noise yesterday.

DLF
08-02-2010, 11:37 PM
DLF, my mistake--delrin it is. Everyone still needs to buy them.


I wholeheartedly agree! :D

Thanks for the endorsement. :cool:

ricardoa1
08-03-2010, 11:13 AM
Try some friction modifier in the pump to see if it gets rid of the noise. Thats what they used to do at the dealership back in the day.

90SC BIG BLOCK
11-04-2010, 11:11 PM
I use a trany cooler for my steering .

Mercutio
11-05-2010, 06:27 PM
I use a trany cooler for my steering .

I do too, now, but it's still not entirely effective.