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Tested my custom FD coilovers, 6'7" FD racer, crashed my car

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Old Mar 4, 2005 | 12:30 PM
  #26  
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Originally Posted by John Magnuson
The Mazdacomp upper shock mounts are:

F128-28-380 - MOUNT, UPPER SHOCK (F-R) (4)
Notes: FRONT AND REAR. THIS IS MADE OF A 40 STIFFER RUBBER THAN STOCK. THIS IS NOT THE BUMPER BOUND WITH THE THREE BOLTS.
These are just the rubber "biscuits" and not the entire rubber mount with the three mounting bolts, correct?
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Old Mar 4, 2005 | 01:23 PM
  #27  
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What da ya want for nothing? ... a rubber biscuit? (Blues Brothers song)

-Max
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Old Mar 4, 2005 | 03:34 PM
  #28  
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Originally Posted by DamonB
These are just the rubber "biscuits" and not the entire rubber mount with the three mounting bolts, correct?
Yes, that's all they are. Kinda pricey biscuits.

Honestly I don't know if their is all that much benefit to putting in the stiffer MazdaComp ones. Mine were in pretty sad shape after 150K miles to I went ahead and got them.
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Old Mar 4, 2005 | 04:03 PM
  #29  
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From: Dallas
Originally Posted by maxcooper
What da ya want for nothing? ... a rubber biscuit? (Blues Brothers song)

-Max

I think it was rubbbbbbbbbbbber biscuit

New Oldsmobiles are out early this year!
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Old Mar 5, 2005 | 01:35 AM
  #30  
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Originally Posted by DamonB
Very sorry to hear about the damage to the car. FWIW I was on different tires for the first time on Sunday at a very fast autox and had the same problems. The car slid and recovered so differently I lept getting caught correcting it too late. Spun it once and nearly spun it a second time but held on after three very big oscillations.
Hoosiers break away a little differently than Kuhmos eh? I found that Hoosiers are faster but less forgiving.
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Old Mar 5, 2005 | 08:51 AM
  #31  
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Originally Posted by turbojeff
Hoosiers break away a little differently than Kuhmos eh? I found that Hoosiers are faster but less forgiving.
After my first time on them I agree.

I also discovered the left rear wheel bearing was shot and letting the tire wobble about 1/16" of an inch. I don't know how much that contributed but when I think back now every time the car was squirrely was in hard right turns. I replaced the bearing yesteday and race again tomorrow so I'll see if that made a difference. It was also damp last weekend so needless to say I haven't learned much about the tires yet.
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Old Mar 5, 2005 | 11:44 AM
  #32  
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john,

sorry to hear about your off track excursion.

as i have repeatedly posted as you go up on spring rate, shock adj, sway bars, and tires it becomes harder to drive at the limit. by that i mean you get less warning/feedback from the car before it breaks loose. that doesn't mean you should go down the above roads.... just don't go too far at once and understand you are raising the bar as to car control.

what tire pressure were you running? too much tire pressure can put you in the weeds in a second. i think tire pressure is one of the most overlooked and important aspects of tuning.

finally, anyone doing track days needs to own, understand and use a pyrometer. they aren't very expensive and are the only way to set your suspension. you might find an analog model cheap and they work well.

good luck,

howard coleman
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Old Mar 6, 2005 | 03:21 PM
  #33  
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Originally Posted by howard coleman
john,

sorry to hear about your off track excursion.

as i have repeatedly posted as you go up on spring rate, shock adj, sway bars, and tires it becomes harder to drive at the limit. by that i mean you get less warning/feedback from the car before it breaks loose. that doesn't mean you should go down the above roads.... just don't go too far at once and understand you are raising the bar as to car control.

what tire pressure were you running? too much tire pressure can put you in the weeds in a second. i think tire pressure is one of the most overlooked and important aspects of tuning.

finally, anyone doing track days needs to own, understand and use a pyrometer. they aren't very expensive and are the only way to set your suspension. you might find an analog model cheap and they work well.

good luck,

howard coleman
No problem! It turned out to be pretty minor. Popped the front dent out myself. Nothing turned out to be bent with front suspension. Just needed an alignment. Still have a fist sized dent at the rear... I'll deal with that someday.

Yes, you're absolutely correct that everything does happen faster. The car was actually performing very well and felt well balanced in my rather amatuer opinion. As much as I'd like to blame my accident on the car it really was much more about driver error.

I usually run 32 psi all around. What do you think about this? Some folks say I should run lower.

Yes, I know a pyrometer is great. I've used them many times before on cars at autocross events. However I have yet to use it for my FD. I also need to cornerweight my FD...
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Old Mar 7, 2005 | 06:57 AM
  #34  
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what spring rate were you running?
how were your shocks set? s/b soft in rear
air pressure should be no more than 30 front, 28 rear set cold for street. at the track start at 30/27 and bleed back down to that setting after every track session. fine tune from there using air pressure.

howard coleman
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Old Mar 7, 2005 | 02:12 PM
  #35  
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I use the RSR Race Springs. Front spring is around 450lb and rear around 390lb. (I think that's 8kg front and 7kg rear). The rear shocks are set to have softer compression than the front.

The car felt pretty well balanced.

So are you saying to bleed the tires down so that they are at 30/27 even when HOT at the track???
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Old Mar 7, 2005 | 08:06 PM
  #36  
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Originally Posted by John Magnuson
I use the RSR Race Springs. Front spring is around 450lb and rear around 390lb. (I think that's 8kg front and 7kg rear). The rear shocks are set to have softer compression than the front.

The car felt pretty well balanced.

So are you saying to bleed the tires down so that they are at 30/27 even when HOT at the track???
Base your tire pressure on how the tires are wearing not what your buddy next to you said. Every car and tire is different and every driver drives differently. Run whatever pressure is giving you the best contact patch in relation to your suspension setup.
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Old Mar 8, 2005 | 05:49 PM
  #37  
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I ran 32psi all around on my last two sets of track tires and they wore down beautifully evenly. Of course now spring rate, shock valving and ride height have been changed so it might be time to mess around with pressures again.
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