Fun night at the drag strip

[fletchusmc]

Was finally able to get back to the drag strip last night. The last time I went was Feb or March and still had the old Pilot Sports on the back. Had a heck of a time struggling to get traction. I now have Nitto NT555 Extremes on the back and the track was crazy grippy last night! My very first run I almost bogged it as I was expecting tire spin again. Was able to pretty much launch at 3k and just hammer down. My second to last run was my best I've been able to run yet, but overall I'm extremely happy for a stock 95 with only a Corsa catback :-D Oh yeah, ignore the red light still working on my reaction times.

http://i1342.photobucket.com/albums/o762/fletchusmc/Mobile%20Uploads/20140718_204704_zpsbtjtbtnf.jpg (http://s1342.photobucket.com/user/fletchusmc/media/Mobile%20Uploads/20140718_204704_zpsbtjtbtnf.jpg.html)

[PhillipsLT5]

1.95, 60 ft, wow, tires are working!

[ZR-1]

Where do you find your best shift points? What suspension setting works best for you?

[Dynomite]

Where do you find your best shift points? What suspension setting works best for you?

What rpm did you end up with in 3rd (113 mph)?
Assuming you did not shift to 4th.

Just curious what loaded diameter tires you are using.
Also assuming stock rear end and stock transmission (you say Stock 95)?

[fletchusmc]

I actually ended up running a 12.6 last November which is my best yet. Planning on going tonight which will be the first time since then. I run the suspension in the softest setting, not sure if it helps but in my mind the softness should (?) help it squat more and transfer more weight to the rear. I wasn't really paying attention to the RPM in 3rd through the lights and I don't have to shift to 4th. I've heard they will do close to 130 in 3rd? Don't know about that one though. The tires are Nitto 555 EP, factory size, and run about 26-28 psi in them. Stock gears and transmission. I would say I shift as the needle is hitting 7k, of course I don't know how accurate the tach is and how much more the RPM has risen from the time I see it hit 7 and I actually shift.

[fletchusmc]

Found the last time slip, left lane. Was one of the newer 5.0's in the right lane. He has since traded it in on a C6.

http://i1342.photobucket.com/albums/o762/fletchusmc/20141113_205948_zpsmc4kqcgj.jpg (http://s1342.photobucket.com/user/fletchusmc/media/20141113_205948_zpsmc4kqcgj.jpg.html)

[Dean Nelson]

nice runs on a stock car!
try running 15 psi in the back, and 50-60 in the front.
run with 1/4 tank of gas.
the soft setting is the way to go
best runs will be with a "slight bog" and go
also need to "power shift" 2-3, and if the track is good also 1-2 but be ready if the track will not hold the 1-2 power shift.

Dean Nelson

[ZR-1]

great, thank you!

[rhipsher]

That's a good 60ft. This is my time slip from 2009 with old hard KDWS tires. Mine is on the left side. The 2008 Z06 was on the right column. I had a terrible time getting traction and my 60ft times were not good. It was 53 degrees that day.
http://i301.photobucket.com/albums/nn63/keeno1970/ZR-1%20reg/timeslip.jpg
http://i301.photobucket.com/albums/nn63/keeno1970/ZR-1%20reg/DSC01538-3.jpg

[haber rj]

Nice looking ride congrats, numbers aren't bad either

[Hib Halverson]

Seems to me you can trick SRC for drag racing. It's been so long but and I can't remember the exact procedure ,but I think, with the key on, you put the switch in Perf, then pull the fuse. Then take the front actuators off and turn the gears until the front shocks are full soft.

That should leave you with firm in the rear and soft in the front. Then disconnect one of the front stab bar links.

All of that will help rear weight xfer.

If you can leave at 3000 rpm with a street tire, the tires work well and the track must be pretty good.

12.6 is pretty darn good for a stock or near stock ZR-1

[rkreigh]

drm makes a modified controller box and a chip that does this

I have the controller box but not the chip

that's a great way to do it and the fronts are ez to get to

thanks Hib!

[Paul Workman]

Here's a chart from Marc Haibeck's site that might be helpful data:

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/ZF6MPH345vs410gearratio-Haibeck_zps837f03ef.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/ZF6MPH345vs410gearratio-Haibeck_zps837f03ef.jpg.html)

The best shift point is result of trial and error, which takes into account all the variables (i.e., reaction time, tune, mods, tach reading errors, lag, etc.) A shift light cuts out the errors associated with analog (tach) errors. That leaves you and your car's particular tune and setup: somewhere between 6300 rpm and up, depending on your mods (if any). My "FBI" porting/tune best results (so far) are with the light trigger set at 7100 rpm. Your mileage may vary!

[Mystic ZR-1]

I like that 6th gear at 7500 rpm!!! :)
I guess you'd want your windows rolled up
and roof panel on?
Probably want to have your passenger hold your beer too...

[Paul Workman]

I like that 6th gear at 7500 rpm!!! :)
I guess you'd want your windows rolled up
and roof panel on?
Probably want to have your passenger hold your beer too...

Yes. Wouldn't want to end up on the "Tree of Woe"!:o

[Bob Eyres]

Fletch, in my opinion you're shifting at just the right point, but those 60ft. times could use some improvement. Anything under 2.00 60ft. is good but every tenth you cut off of that is a good 2 -3 car lengths ahead of a competitor at the finish.
It sounds like the strip you're running on has great traction. So I'd use 20 lbs. of air at the rear to create a bigger footprint, and do a good seven second 2nd gear burnout to really heat them up.
Launch at 4K - 4,500 rpm, and don't drop or side step the clutch. A softer clutch engagement helps save your half shafts from shearing. A quicker 60ft. time of 1.70 -1.80 will translate into much more than one or two tenths in the traps. You will be in the low twelves.
Hib's tip about the front sway bar, and the shocks is very good, and allows more weight transfer = more traction in first gear, and probably another tenth advantage overall. All this stuff adds up....oh, and pull out that air filter too. Let that puppy breathe.

Good Luck.