Going to the track tomorrow at Mokan in MO. I really really would like to come home with an 11 second pass.

Previous best was 12.24@110.38 with a 1.77 60 ft. Car was running 7.8@90mph 1/8th mile, so while some here disagree I feel I was shy a mph or 2 on the big end. DA that day was 1840ft

Car was hitting the rev limit for a moment on the 2-3 shift which might be the blame. I will have that corrected this trip.

The track should also be more seasoned, but it's a street car track day so the launch pad might not have a lot of rubber laid onto it. I was light on the launch last time to prevent blowing the tires off.

I would like to see a bottom 1.7 60ft or a 1.69 but I might be dreaming. Car will be on 325/50r15 MT ET street radials because that's what I have. They are almost new. Seem to like 18psi and a good 2nd gear burnout.




Since then I have/will:
1) disconnected front stock SS sway bar end links
2) loosened and double nutted the lower control arms
3) right at the muffler I cut off the 2.25" tails pipes over the axle ( I run cutouts in the 3" pipe ahead of the mufflers so this was more for sound/ weight loss than flow but can't hurt)
4) adjusted PCM shift points to prevent getting stuck on the rev limit and having to lift for the pcm to shift to 3rd
5) will be doing fresh oil change today
6) going to add some octane boost to prevent getting knock retard on the hit
7) going to try running rpm up on the converter some and see if it sticks better than launching off idle



Any other small things that I can do which might add up?
I'm afraid the DA is going to kill us with humidity and 80* temps tomorrow, but if I even get a pass that would DA correct to a SOLID 11 sec slip I would be moderately happy.

I will empty the car of everything I can that isn't bolted down. I don't have interest in pulling seats or things as that ruins the spirit of an "11 second street car" to me.





SPECS:

1971 Chevelle, educated estimated raceweight 3680-3720lbs

ls1
Comp 230/224 reverse split .57x/.56x lift, 111+3 lsa, peaks at 6000rpm, shifts commanded at 6300 rev limit at 6500
Fast 90mm intake (lightly ported by me)/throttle body
K&N cone filter on a 3" ID 90* rubber coupler
1 3/4" longtube headers
3" pipe to 3" cutouts to flowtech terminator mufflers, no tails

4l60e rebuilt with Alto clutches, beast sunshell, transgo kit, etc
Yank SS3600 stall
3.5" chromoly driveshaft, high speed balanced
12 bolt, 3.42 on Eaton posi

325/50r15 ET street radials on 15x10 TTII wheels

 

Converter is going to have a big impact on your overall results. Either by dropping weight or increasing it will you start seeing better results. Are you recording knock retard already??

 

If I end up with poorer quality 91 octane it will sometimes get 1-2* retard on a heavy first gear load.

The 60ft are slow because I could only hammer 1/2-3/4 throttle last time due to poor prep on the track. If it sticks a WOT launch the 60ft will come down.

 

there is no way that car should spin on those tires unless you are racing on a skating rink. my 255/50/16 mt et street drs liked 14-16lb. i had a hard hitting converter, but even on unprepped tracks (street car nights...) it still went 1.62-1.60 with a nuclear burnout, of course. that car hooked everywhere, i swear it'd go 1.70 on the street haha.

if you get it to hook and pick up the few missing mph on the top half you'll easily find your 11 second slip. just getting the 60' where it should be will put you ever so close.

edit: how did you get the car so light? i had a 71 ss chevelle with iron 355 sbc, th400, and 10 bolt rear...it weighed 3820 w/o me in it. i think i just answered my own question haha.

 

ls1, no sound deadening (car didn't get any louder inside without it), ac delete, and just odds and ends...its full interior and such

street weight with my tools, mostly full tank, subwoofer box, etc is 3820 with me in it (I am only 130lbs though)

sub box is 45lbs all by itself, tool box is at least 20, couple other things I pull too

 

I agree with people above..You are going to have to get a 1.6 or better 60' to carry you to an 11. That's how I did it since I don't have a lot of hp. You probably need a cool day with low D.A. also. I am not sure if that SS3600 can do it??

 

I don't think that 3600 is going to do it either. Plus a Chevelle is not known to be too aerodynamic.

You might need something more like a 4000 or get the motor to make more power or put more gear in the car.

 

Another vote for getting that 60ft down. Play with the suspension....what shocks are on the car??

 

It was hot/humid (3000ft DA), best of the day was a 1.8 60ft, 12.40@109mph. I am fairly happy with that...that calculates out to 11.9-12.0 @112-113mph in 0DA. Not bad for having a **** 60ft and a car with a front end like a brick. I would LOVE to run in some negative DA for a change.

I did win the heads up street event, beating a GT500 on drag radials (not sure what mods, car used to run a Blowzilla but has been demodded to "almost stock") who was running mid 12s at 112-115mph.

I couldn't hook to save my life. Looking at videos I think a longer burnout might be in order next time. I did a few seconds in first then shifted to 2nd and held a few more seconds. I think the car should go a low 1.7 60ft at least since my best was a 1.77 at partial throttle.



I have some 799 heads to port/mill and install, just haven't got them done yet. Was hoping to make an 11 happen before they went on, but whatever.


Car has AFCO circle race shocks and stiff (750#) springs up front, rear are hotchkis lowering springs and KYB Gas-a-just shocks. The car is set up to corner flat, so that's hurting the hook some, but I would still think a decent prepped track could hold the car on 325/50r15 MT ET streets...I've outlaunched an Evo X on the street with them.