Alright, I have not posted in years, I find the search feature to be good enough for 99.9% of any questions I have. I have searched but could not find anything specific to my question.

I have been running the Ground Control upper mount for my fronts only, for the past 2 years, and I am considering getting the upper mounts for my rears. Reason being is that on some of the higher speed courses, I'm hoping to get a little better high speed stability. I have basically set up the car, so that my rear end is stiff, and is basically being dragged around by the front, which has worked well for the small, tight courses.

I race in SM2 with my 91 CRX with a b18c transplant, on the longer faster courses, I am at serious disadvantage to the Corvette's and 911's, which I feel are better at the high-speed cornering.

Will the rear upper mounts help me with the high-speed transitions?

Thanks, Mac

 

The only thing the upper mounts do is give you more suspension travel. If you are not bottoming out the shocks right now they will do nothing for you.

 

Have you replaced the bushings yet? If not that may be part of your problem, espeically the rear TA bushings.

If you have done them, then you may need to adjust your set up for high speed events alittle. You can not run as tail happy setup as you do on tight courses. The rear stiffness you need to get the car to rotate like crazy on tight stuff can come back and bite you on high spped stuff. Ask anyone who has tried to do a track event on their autocross setup. Talk about LOOSE.

 

I'm not sure if I'm bottoming out ( I don't know if I want to find out ) I may be close, when pushing it in the High-speed corners.

I do set up the car different for the bigger courses, looser rear, tighter front, which leeds me to think I'm getting close. All bushings have been replaced, at least once.

The most noticible difference with the fronts, is the drive to the race, on our crappy roads.

Mac

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sircrx5 &raquo;</TD></TR><TR><TD CLASS="quote">I'm not sure if I'm bottoming out ( I don't know if I want to find out ) I may be close, when pushing it in the High-speed corners.
Mac </TD></TR></TABLE>

put a Zip tie on your shock shaft.. go run a session then look for the zip tie.. if its stuffed into your bump stop you know your bottoming out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BrianZ &raquo;</TD></TR><TR><TD CLASS="quote">

put a Zip tie on your shock shaft.. go run a session then look for the zip tie.. if its stuffed into your bump stop you know your bottoming out.</TD></TR></TABLE>

That's a great tip, Thanks Brian

Mac

 

I just re-read your original post. You are talking about high speed cornering and high speed transitioning. These are different things, which are you having problems with?

You said in the next post that you change your set up in faster course to be looser in the rear. I may be misinterpreting what you are saying, but let me try this again. You are probably not going to want your car to rotate as much in the rear on the fast courses as you would on slow courses. Loose in the rear usually means the rear is rotating more.

As for the Zo6's and other cars of that nature, hate to say it, but on a fast course where they can open up and use the power they have you are going to be at a disatvantage. That is the real advantage they have on fast courses.

I don't know if any of this helps, but oh well.

 

Sorry my phraseology may be off. High-speed cornering= cornering at high speeds. High speed transitions=Passage from one form, state, style, or place to another at high speeds, a simple example could be slaloms.

My car, the tighter the rear end is (stiffer), overstear is induced by a quick off throttle or tapping the brake and letting off the throttle quickly.

I agree my problem is H.P. or more specifically torque, I guess I'll have to get a SC

Why on earth they put CRX's and Z06's, 911's in the same class is beyond me, when crunching the number's, maybe there wasn't enough info, on the differences, if each took it to the limits of the rules. Oh well I have fun anyway! I appreciate the help, Thank You, Mac

 

How long have you been AXing? realistly on the local level you b18 CRX should have no problem, with exotics on autocross course, barring national champions and the such.

The Upper mounts unless you are bottoming out will not help you at all. I would suggest some stickier R-compounds. But first do feel that you really are as good as you can be.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mattamotor &raquo;</TD></TR><TR><TD CLASS="quote">How long have you been AXing? realistic on the local level you b18 CRX should have no problem, with exotics on autocross course, barring national champions and the such.

The Upper mounts unless you are bottoming out will not help you at all. I would suggest some stickier R-compounds. But first do feel that you really are as good as you can be.</TD></TR></TABLE>

My main competition is a National competitor, and if he brings his national car out to play, I have only beaten him when he cones. I do very well, all the other times.

I have been AXing for six years, he has been AXing for at least 25. I run 235/45-13 Kumho's. I will try Brian's advice, and that should clearly tell me where I'm at, and if I need to bother with the rears. I will also try setting up the car, as much as I can, for high speed, next race. I usually do pretty good, and sometimes don't want to bother with my set-up. I will have to approach this with a different mindset, of the 2 or 3 different tracks we run on, 1 is extremely large and fast and another is exactly the opposite, of tight and technical, He won't even bring his big dog out to play on that one.

I appreciate the help, as you all know, each year the ante get's upped, and if your standin still, chances are you may be fallin behind. I was in search of something to help. You are right on with " feel that you really are as good as you can be." I will have to bring my A game for sure, and see what I can do, I know last race I left some time out there, nowhere specific, I think I just needed to push it to the limits throughout the whole course, maybe I played it safe, I felt like if I had a 5th run, I could have done it.

Thanks, Mac

 

Who is it you are running against?

 

Bruce is his name, when he brings the Big Dog out he usually get's FTD

 

Bruce Wentzel, specifically.

I think you may be able to get the stability you need with more front shock and more air in the rear tires. At least try that, before phyically changing the suspension.

BTW, the first SCCA event for us is at The Palace on Memorial Day, iirc...