It’s only a secret if you don’t know it. For the betterment of our series and to help level the playing field let me share some of what I’ve learned over the years.  Some of you know all of this (and more) but you weren’t born knowing it, you learned it somewhere . . .


Tire Pressures

What are you doing?  I need 44 PSI in my right front.  I hear others as low as 35, some as high as 50.  When you drive it in deep and the left rear comes off the ground, where does all the weight of the car go?  Pump that right front up to take the load and not roll under so much.  The tires I run, Sumitomo HTR 200’s are listed as max 51 PSI.  I figure starting at 44 they must get somewhere close to that when warm, but I’ve never checked them after the race.  For the right rear, it depends if the car turns good or not. If I have the same size tires on all 4 corners, then I put the same PSI in the right rear as the right front to keep the diagonal in check.  Otherwise she’ll get a little pushy.



Tire Sizes

To be clear, we allow different tire sizes (usually referred to as stagger) in the ISS.  Same rim size but any combination of legal tire sizes.  On dirt tracks I always try to run one size (or two) larger on the right rear.  Then I can lower my right rear pressure.  So let’s say a 185-70 is on the right front, I’ll put a 195-70 on the right rear.  I’ll still run my 44 PSI up front, but then only about 30 in the right rear when I’m staggering the tire sizes like that.  Works on blacktop as well, but you don’t want to be too loose on asphalt, makes for a real long day.  Also, your tires should be appropriately sized for your engine RPM.  If you are hitting the REV limiter halfway down the straights go up a size or two, or consider a smaller tire and 3rd gear. 



Tire Shaving

Brand new tires don’t work that well, at least not on the right front.  Tread that is full depth wiggles around a lot under heavy loading (cornering!)  Eventually, it “chunks out” and the car’s handling really goes away.  When you are setting up for your next race, choose a right front that is wore down to the wear bars or further.  That will be a longlasting (and fast) tire.  Fast guys sometimes find the perfect tire in the junkyard, but usually they just buy a brand new Sumitomo HTR 200 and shave 2/3rds of the tread off before they even put it on the car.  If you are shopping used tires, look for the lowest “treadwear” number you can find.  A long-lasting tire (high number 500-600) is made of hard rubber and won’t be real fast.  A soft tire (like a Sumitomo) will have a treadwear rating closer to 300. 



Camber

The reason I am so quick to allow camber in my series is that it saves the front tire.  Some series/tracks won’t even allow a quarter inch.  I can’t run 100 laps without junking out a right front tire, let alone 200-300.  Now I know there are other ways around the tire wear, like slowing down (never happens) or rear steer, but camber just makes sense.  It put’s all the rubber down at once when you need it most.  The rules allow up to 1 inch.  GET EVERY BIT OF IT! Keep the right front tire on the car! 


Some cars are more easily adjustable than others.  GM makes an ecentric bolt kit. NAPA sells expensive ball joints for Hondas.  Escorts are the easiest to camber up (imho).   Often, camber involves the use of a die grinder to oval out some holes.  Sometimes we have to tack weld “adjusted” pieces in place to hold them there.



Brakes

Hello – you use them 600 times in a 300 lap contest just to turn laps.  (Plus red flags and obstacles.)  They better work and I do mean all 4.  The fast Escort GT’s almost always have had their rear calipers replaced.  You may not have rear discs, but you better have working rear brakes and adjust them up!  Front brakes only will really make a car push. 


FLUID – I never could get away with regular DOT 3 fluid.  My brakes are always flushed out and well bled with DOT 4 fluid.  Some guys even buy the expensive “racing” brake fluid.  I bleed my front brakes in between every race.  Always seem to get a few bubbles out.  Maybe you’ve noticed after a red flag the brake pedal isn’t always there on the restart!  Maybe takes a few laps to come back – use better fluid


PADS AND ROTORS - I always put a fresh set of pads on the front for an asphalt race.  Another one I learned – never use a $10 China rotor on the right front (they break out the center).  I’d rather have a used OEM or I break down and buy a $40 brand name one.  China rotor seems to be fine on the left front.


HEAT? - One last thing.  Are there any bind or tight spots in your caliper slides?  I always wire brush slides/surfaces and antisieze them up well.  You’d rather they were a little loose than dragging down the straightaways and getting hot for no reason.  On the old GM rear wheel drives we would always take out the antirattle o-rings and yeah they would bang around compared to a street car – but they never had any drag.