New personal best 1/4 mile!

[Fourdoor]

Took another trip up to US-41 dragway. I still am unable to log A/F ratio, so I haven't tweaked the A/F maps very much... just richened it up for high boost levels where the tune was a bit lean.

Track elevation 662 ft. Temperature 55 F. Vehicle weight with driver 3710.

My first run I F'ed up. Getting the data logger going I forgot to turn off ASC and forgot to switch the transmission into Sport mode. I ran a 13.399 @ 102.05

My second run was my new personal best... remembered to turn off ASC and switch to sport mode and pulled off a decent launch. I ran a 13.052 @ 103.70.

The car was feeling strong, and I think with one more run as temperatures cooled off a bit I would have gotten my 12 second run, but before my second run the left lane got messed up, and about 10 min before I would have made my 3rd run somebody oiled down the right lane

HP estimates based on track times are for fun, and comparison to other similarly derived estimates... that being said, my best run results in the following:

ET method 330 CRANK HP
Trap speed method 323 CRANK HP

It has been my contention in the past that the trap speed is more accurate, and I see no reason to change my tune when it is the lower of the two estimates of crank HP.

Theres always next weekend! If I have enough chances to run I may try holding 4th to the end... with my raised rev limits I can hit 107 mph at the top of 4th (7,500 RPM)... but boost drops off very fast after 6500 RPM so I don't know if the gearing advantage would be worth the boost drop... we may see next time I hit the track!

My only changes other than tweaking the tune just a bit was swapping out the test pipe for my high flow cat. My peak boost in 1st was 23.6 psi dropping to 15.6 at the shift, 2nd peaked at 22.7 dropping to 15.5 at the shift, 3rd peaked at 22.2 dropping to 16.7 at the shift, 4th peaked at 23.6 dropping to 16.5 at the shift, and finally 5th peaked at 24.8 and dropped to 22.6 at 5500 RPM where I let off due to passing the finish line. I only logged boost my first run to make sure it wasn't excessive, second run I tweaked my timing curve and logged knock sum.

Time slip will be posted in the drag race forum as soon as I get it scanned.

Later,

Keith

[IdriveRA]

Good job, you def. picked a nice day to run it!

[kaiten2]

Congrats and good times. It would be awesome if you can break into the 12 sec mark good luck

[Tappington]

How does turning off the ASC help? Does it help on the launch or just the entire drag run?

[Fourdoor]

Originally Posted by Tappington

How does turning off the ASC help? Does it help on the launch or just the entire drag run?

The track I run at actually has pretty good traction at the launch area, so it probably makes little to no difference. If the launch area is a bit slick it is a whole nother story!

The way our ASC works, is it cuts engine power for a second (not sure how long) if it detects wheel spin. On a drag strip run a little bit of wheel spin isn't good, but much better than having engine power cut off for a second or so... if that happens it is pretty much game over on a drag strip run, so you turn off the ASC.

Keith

[billyboy1]

that is good to know

nice run!

[show time]

Very nice indeed. If you weren't in the hatch you probably would have hit the 12 ish area. Nice sold run. Keep up the good work.

[Fourdoor]

Originally Posted by show time

Very nice indeed. If you weren't in the hatch you probably would have hit the 12 ish area. Nice sold run. Keep up the good work.

Hell, if I had taken a dump before the run I probably would have gotten my 12!

I'm pissed at myself for not going earlier and getting more runs in, and for arriving with over 2/3 full tank of gas.

I just need to tweak my logger for the correct readout on A/F ratio, and I can get the A/F tune more accurate. Right now it swings between 11 and 12 at WOT high boost, I want to steady it down at a nice safe 11.5 to 1 and then start playing with the timing maps a bit now that I can log knock sum.

Keith

PS: After I get the 93 octane maps lined out I will start tuning on E-85 God I love that stuff!

[RA173]

Nice run, now go get that 12 second pass