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  • 2 weeks later...
Congrats on the time, your killing it now

Thanks dude! I still have a long way to go; my short times aren't good. I finally managed to crack a 1.9x 60' time this time out. But you'd expect that with DRs and a lot better, too. Got to work on the launch a lot more.

The DRs are still ripping through in 1st, 2nd and 3rd so when I put the slicks on we should see another big bite taken out of the ET. Also interested to note that the trap speeds actually went up when I moved from street radials to DRs!

Different rolling diameter could contribute to that, mate.  It effectively changes your diff ratio.

Adrian

Adrian, the rolling circumference actually decreased which should give me shorter gearing (and therefore less trap speed). The street radials are 25.9" and the DRs 25.8" tall.

But I also changed diff ratios in between 23/6 and 14/7 to a tad taller to combat the wheelspin.

I think the higher traps was because I wasn't ripping the tyres through in 4th and 5th with the DRs.

Adrian, the rolling circumference actually decreased which should give me shorter gearing (and therefore less trap speed). The street radials are 25.9" and the DRs 25.8" tall.  

But I also changed diff ratios in between 23/6 and 14/7 to a tad taller to combat the wheelspin.

I think the higher traps was because I wasn't ripping the tyres through in 4th and 5th with the DRs.

surely a shorter effective diff ratio will give you a higher speed

it is obvious from the terminal speed that the car is severely undertyred.

I don't think so. Dunno what forum you think you're on but Kenny's trying for quick times on radials. It is also pretty obvious that you're unaware of the experience level of the driver in question. I say let him go and watch the times fall. I dropped almost a whole SECOND by changing NOTHING but my level of experience. Not everyone's a seasoned racer straight off the bat.

Adrian

it is obvious from the terminal speed that the car is severely undertyred. I used to regularly run a car that ran 10.2 at the same terminal with virtually no tyre slippage. sixty foot is pretty ordinary too.

Yes if you mean by undertyred that it gets wheelspin. Unfortunately a 10" rim with 11" wide rubber is all that fits! The street radials are 285/35 R18 and they ripped through in all gears. The BF Goodrich Comp TA drag radials are 275/50 R15 and they turn through in the first three gears and pop in fourth. There is plenty of time lost in there I agree. I haven't run the MT ET Drag slicks yet because I am waiting for the front runners to be made up.

So I can agree undertyred becaues I haven't run with slicks yet but how many cars that run 10.2 do it without slicks?

On my short times I'll have to cop that on the chin! I did manage to pull off a slew of 1.9x and 1.8x short times tonight so I'm happy that I am at least improving.

Thanks for being a little ray of sunshine!

I don't think so. Dunno what forum you think you're on but Kenny's trying for quick times on radials. It is also pretty obvious that you're unaware of the experience level of the driver in question. I say let him go and watch the times fall. I dropped almost a whole SECOND by changing NOTHING but my level of experience. Not everyone's a seasoned racer straight off the bat.

Adrian, thanks for the support dude. I managed to drop from 12.6 to 12.1 and from 11.3 to 11.0 without any changes to setup by improving my technique. I am the first to admit I am a beginner and have a lot of room for improvement in all aspects. But I can tell you that I am having a whole lot of fun learning!

Adrian, your encouragement is always appreciated!

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