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DIRT69
05-02-2011, 07:44 PM
slick track gears
im kind of confused on what gears i need to run. when the track slicks off to blowing dust i know there is no setup in the world that you will be able to run wide open off the corners. we have been taking gear out to help keep from blowing the tires off down the straights. is there a point where that will start hurting us or should i look at maybe slowing the 4 barrel from kicking in so early?? i could only run about 1/2 throttle befor it would spin the tires down the straights?? thank you for any help.

Matt49
05-02-2011, 07:59 PM
Try disconnecting your secondaries.

DIRT69
05-02-2011, 08:07 PM
that was my next idea to try on a practice day, or retard the timing

MasterSbilt_Racer
05-02-2011, 08:07 PM
First let me say I have seen people be successful going either way with the gear when the track slows down. I will say that I believe you should use a lower gear (go from 6.00 to 6.24 for example) when the track slows down. The car is going slower so you will need to make this change to keep the rpms about the same. You should do this because your engine is designed to operate in a certain rpm range. Depending on the torque curve, you may kill your engine going too low in rpms or you may find a point in the curve that isn't smooth and blow the tires halfway down the straight.

A lot of keeping the tires hooked belongs to the driver, but there are things you can do. Be easy with the gas. Increase the pedal travel vs carb linkage travel by attaching your throttle linkage to a lower point on the pedal throw. You can change your secondary linkage on the carb to make the back barrels come open more slowly. You can take a couple degrees advance out of the ignition timing.

There are situations where 50% throttle will win the race though.

DIRT69
05-02-2011, 09:39 PM
do u think that if you would soften- or stiffen the 5th coil it woudl help you overal forward traction?? or could it be because i was only up 2 holes from the bottom on my lr top bar?? the car is awsome getting in and to the center on and off the gas but when i try to throttle up from center off and down the straights i can spin the tires at any time??? im at about 70 lbs wedge???

charcoal01
05-03-2011, 10:07 AM
i used to be under the same assumption that i had to take gear out of the car (lower overall gear number) in order to keep the car hooked up on a slick track. finally let a chassis guy who's a friend of mine convince me to run more gear. seemed totally backwards to me but i've run my fastest lap times and actually turn less rpm now. the gear helps slow the car down when you get off the gas and allows you to use less brake. less brake means less likely to slide your rear tires, which means you're not having to work the throttle to get the tires hooked up back up again. the gear also helps give the rear end mechanical leverage and gets the car/keeps the car up on the bars, developing traction sooner. like the guy said before, you just have to be totally smooth on the throttle. let the taller gear help get you up off the corner without having to use so much throttle and then lay it down once the car is straight. but you have to transition slowly! ease off the throttle getting into the corner and very slowly pick it up as you're going through the apex and starting to come off the corner.

MasterSbilt_Racer
05-03-2011, 12:09 PM
do u think that if you would soften- or stiffen the 5th coil it woudl help you overal forward traction?? or could it be because i was only up 2 holes from the bottom on my lr top bar?? the car is awsome getting in and to the center on and off the gas but when i try to throttle up from center off and down the straights i can spin the tires at any time??? im at about 70 lbs wedge???

A 5th coil change MAY help you some. The same spring won't work for everyone or every engine/gear combo. You have to find what works for you in getting the load to the rear tires quickly without shocking them loose.

hall99
05-03-2011, 02:07 PM
It sounds like you are on a really slow small slick track if so don't be afraid to go soft on all of your springs and take more bite out.

hpmaster
05-03-2011, 04:29 PM
I found the soft fifth coil, as low as 250, didn't help much on slick. I have run from 620 to 676 gear and cant say that was a game changer either. Overall softer springs and throttle control seemed the best thing.

4bangerhotrod
05-03-2011, 06:43 PM
we always go to a little lower gear when the track slicks off. the lower gear makes it easyer to be smooth on the throttle on exit plus if the tires break loose an you ease up on the throttle to hook the tires back up with the lower gear the tires will catch the track faster cause with the lower gear when the tires break loose they dont spin as fast as the tires would with a higher gear so this allows the tires to not have to slow down as much to hook up. example the track will hold 6000 rpm, with a 6.00 gear the tires break loose and the tire rpm runs up to 8000 when you lift but with a 6.21 the tires only run up to 7000 rpm. so which gear is goin to be easyer to peddle.