First time to track! Finally! [Archive] - Chevelle Tech

: First time to track! Finally!


thunderstruck507
Nov 6th, 04, 10:21 PM
Got quite a few runs but most sucked, I was having severe trouble with the car trying to die on the light...when it didn't it I got tire spin.

Best run was:

Reaction: .871
60 ft: 2.305
MPH: 75.76
ET: 9.474

Best MPH was 77.6

I don't know what caused it to fall off. Hopefully next time the stalling won't take place. I think it could have been bad gas or bad carb tuning.

Slowpoke70
Nov 6th, 04, 11:55 PM
graemlins/thumbsup.gif

What's your engine/drivetraing/tire combo?

Sounds about right for a 9:1-ish 355/TH350/3.xx gears. Mild build. That's about where my friend runs. But we've done minor tuning to his to get it to 9.39@74ish (not sure on MPH).

EDIT, just saw you 60' time, my friend runs his 9.39-9.45 times on 2.1xx 60's.

I think you have air shocks? or it looks like it from the pics? My buddy's ride has them too and its real sensitive about pressure, anything over 60PSI or so and his 60' goes out of wack.

thunderstruck507
Nov 7th, 04, 1:39 AM
355
882 heads ported
falt top hyper, 4 relief
comp 268h cam (.454 lift)
performer intake
holley 650 spreadbore
HEI w/MSD wires
headers, 2 1/4 exhaust, rear exits
700R4
12 bolt 3.08 gears

These times were with my subs and tools and the rest of my crap in the trunk. Prolly at least 170 worth of dead weight.

Yeah I have air shocks set at 40lbs, my problem was the engine trying to die if I just stomped it from stop...had to ease into it and i was still getting some spin. No burnout cause brakes wouldn't lock long enough to spin and I didnt want to drive through the water box.

There's a bit of potential left if I get the car running right and stop falling asleep at the line...

thunderstruck507
Nov 7th, 04, 1:42 AM
295/50/15 BFGs

A/C unit is hooked up and everything...

Does anyone know if Virtual Engine Calculator gives HP at crank or ground based on ET?

Slowpoke70
Nov 7th, 04, 3:26 AM
I think you have some tuning to do. Your cam and ported heads, better CR and ignition should put you quite a bit faster than my buddy. Granted, you do have a lot of extra weight but I'm sure that's over the rear wheels? Should help you hook.

With the 700r4, your first gear should launch like a TH w/3.7x gears, that together with the relatively short tire might be why you're spinning so easy off the line? Also I hear the 700's gears aren't the greatest for racing.

What's your timing set at?

Is your holley a Vac Secondary carb? If so, which spring do you have in there? If it is too soft, that might explain why it is trying to die on you when you nail it.

thunderstruck507
Nov 7th, 04, 1:37 PM
Its mech. secondaries, whatever the problem is just started yesterday. Up until then it has been starting on the first crank and behaving very nicely.

I know the 700 isnt the best race tranny but manually shifting it, it doesn't feel too bad.

I'm gonna try to go over everything and next time I'll lighten it up to see what I can do, I wanted to see full street trim results.

My compression ratio actually is prolly between 8.5-9, not the best but I'm getting 0ver 20 MPG on 87 octane with it...so I don't expect it to be a beast.

travis g
Nov 7th, 04, 1:46 PM
I assume you are racing at Paris? Is it still a 1000' track, or did they shorten it 1/8 mile?

thunderstruck507
Nov 7th, 04, 5:21 PM
no I was racing at Salisaw, it's closer to where I go to school (Fayetteville AR)

Slowpoke70
Nov 7th, 04, 10:35 PM
Well, with Hyper pistons you should be close to 9:1 since most hyper pistons have the correct pin height. I run cast pistons in mine and I have around 8.3:1,

my car runs 10.1x@72 in the 1/8th through a TH350 and 2.73s, 600cfm VS, headers, 2.5pipes with 50s flowmaster, full tail pipes. My cam is tiny though 256/260H Comp Cams.

thunderstruck507
Nov 8th, 04, 12:57 AM
weighed the car today

with me and 1/2 tank its 3860 lbs

mr 4 speed
Nov 8th, 04, 10:11 AM
Nice looking car thunderstruck graemlins/thumbsup.gif

Looks like you have some high 13 second potential there,but you'll need to do some tuning and get that 60 ft. down.
Your 1/8 mile indicates about a 95-97 1/4 mile speed,which is whats needed to get into the 13's with a decent 60 ft.

thunderstruck507
Nov 8th, 04, 10:52 AM
Thanks Chris,

I'm gonna go back once I get the problems worked out, after driving the car a lot more yesterday I'm leaning towards having got some bad gas on my way to the track...

gared69
Nov 8th, 04, 12:30 PM
Thunder, what rpm were you shifting?

thunderstruck507
Nov 8th, 04, 1:15 PM
My tach is busted so I'm not sure, I was going by ear and trying to shift before I noticed a lack of acceleration. My guess is in the general 5000 area since the tranny shifts itself at around 4500 at full throttle.

Inconsistent shift points could be the variable in my MPHs.

Track wasn't too stable and the car was trying to kick sideways on the 1-2, I was holding second through the lights since my time dumped a bit when i shifted the 3 earlier

I was mostly using this trip for experience and practice with strip technique. I should have the tach and carb both in perfect order in time to go to Tulsa this month (crosses fingers) or at least back to Pier 7 @ Sallisaw

With my best MPH (77.32) and weight (3860)can someone here clarify aprox. engine power? Vurtual engine says 327 or so but I don't know if that is flywheel or ground power.

thunderstruck507
Nov 8th, 04, 5:51 PM
Well went out today to warm up the car before adjusting the carb...after it was warmed I hit a redlight so thought I'd use the opportunity.

Spun the tires all the way through 1st by loading the converter and stomping it on green. Whatever my problem was at the track seems to have disappeared without tuning. Must have been trash in the fuel or maybe the secondaries were trying to hang open

Slowpoke70
Nov 8th, 04, 10:39 PM
Maybe it was that you were hooking better at the track? I've heard that when you hook better, sometimes it causes a mean bog that wouldn't otherwise be there.

thunderstruck507
Nov 8th, 04, 10:45 PM
Track seemed pretty loose since I was still getting some wheel spin. Would seem more likely had it not been for the problems getting the car to start.

I think it's very likely the secondaries were trying to hang open and flood it.

Gremlins gone now so maybe next time will be better. Important thing is I had a lot of fun and got some experience.

Slowpoke70
Nov 9th, 04, 2:15 AM
graemlins/thumbsup.gif Sure is fun, addicting too.

thunderstruck507
Nov 9th, 04, 3:03 PM
Thats an understatement, lol

Now I just wish I had the money to go back this weekend.