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Discussion Starter #1
Yesterday I got my 4th red light of the season, which is more in one season than in years. All of them have been less than .015 red. Yesterday's was .001 red against a .272 red in the other lane. I was the slow car, so....
I know that the roll-out at this track is shorter than where we used to race, as double bulbing is fairly common for anyone who comes over from the other track. I run stock torsion bars on my Dart. Do I want to lower the nose to get more rotation of the chassis before it moves, or raise it to kill some reaction time?
For the record, dropping 3 sizes on the accelerator pump squirters took .005 from my 60' time, and I shaved another .15 from the ET.
 

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All the advise above is good . Might consider a second set of larger fronts for that track . I would start with front tire pressure and move to launch rpm followed by larger fronts
 

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I've experimented with front tire size and hitting a pro tree. Doesn't do squat on my car. RPM without a doubt made the most difference. I leave at 4,200 in S/ST and usually carry between .090 and .100 in the box (.470 tree). When I race S/G I go up to 5,000 and carry .015 to .20 (.370 tree).
 

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I've experimented with front tire size and hitting a pro tree. Doesn't do squat on my car. RPM without a doubt made the most difference. I leave at 4,200 in S/ST and usually carry between .090 and .100 in the box (.470 tree). When I race S/G I go up to 5,000 and carry .015 to .20 (.370 tree).
Maybe the difference in the tire going up or forward , I don't know . Front tires size and pressure will move mine pretty good . I have a ton of front end travel also . If it was my truck in this situation I would add .020 to the delay button and adjust from their . The other option would be take 400 rpm out of the 2 step and see what that yields . Also could probably use more info about the type of racing footbrake vs no box
 

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Discussion Starter #19
Thanks for the input. I'm foot braking with 26" tall M/T's on the front. I have been running them at 32-35 psi, so I could drop them back to 25. As for the actual launch, I have found that the car is pretty much .05 quicker launching with a 12-1400 rpm load against the convertor but is more consistent with a 2000 rpm pre-load. My assumption is that would somewhat negate any gains from lower rear tire pressure. Right now it seems that 15 psi is the sweet spot in the back tires (Hoosier 9 x 30 radial drag slicks). The odd red light is obviously a fact of life, but when you run up a string of bulbs that'd make Amsterdam look like St. George, Utah, you know that there is something else at work or something that can be worked on given how tight they are.
 

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For the record, dropping 3 sizes on the accelerator pump squirters took .005 from my 60' time, and I shaved another .15 from the ET.
Let me understand this better. You dropped acc pump squirters from say a .035 to a .032 and picked up .15 in et? That must be one heck of a hooking track that you can log and see .005 in 60' after just a squirter change.
 
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