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more consistent 60's, ET's..?

Posted: Thu Oct 10, 2013 10:58 pm
by raynorshine
any ideas, tips to get more consistent 60's? even as track, air improves...etc??

Re: more consistent 60's, ET's..?

Posted: Thu Oct 10, 2013 11:27 pm
by GARY C
Relocating weight are adding weight to the correct area, it may just be as simple as adding fuel for weight until the car is perfectly consistent and then topping off after every pass, I have seen a gallon of water mounted high just in side of the trunk lock be the difference of leaving or blowing the tires off.
In my 72 Nova I scaled all 4 corners and found it to be 125lbs light on the right rear as well as heavy on the left front (driver included) so I moved the 2 nitrous bottles from left rear trunk to right rear passenger floor and added 100lbs to the right rear on the back of the wheel tunnel and achieved a 50/50 front rear weight with all corners being even and it didn't require the full 125lbs it was off, the car hooked good enough that I had to travel limit the front end to allow the rear tires to slip 1 1/2 revolutions for the best 60 ft.
Although it wasn't a lot if it stuck the tire at the hit of the throttle it was 1.56 if it slipped the tire it was 1.50 60 ft, oddly enough the next engine was 70 ci smaller and pulled 1.48 60ft by allowing the nitrous to be progressed in faster and never picked up the front tires.

Re: more consistent 60's, ET's..?

Posted: Fri Oct 11, 2013 3:18 pm
by levisnteeshirt
what ya got ?

Re: more consistent 60's, ET's..?

Posted: Fri Oct 11, 2013 9:56 pm
by raynorshine
levisnteeshirt wrote:what ya got ?
1st generation camaro door car, 2650 pounds without driver
-BBC 427, methanol injected
-5500 stall powerglide, 1.76, 4.86 rear
-14x32 tires
-10.12@130.7mph
-1.42 to 1.46 sixtys last time out...car got quicker as track improved

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 8:37 pm
by levisnteeshirt
pinion angle ?

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 9:08 pm
by raynorshine
levisnteeshirt wrote:pinion angle ?
not sure? go on, school me on why, how that would make inconsistent 60's etc..

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 9:18 pm
by af2
raynorshine wrote:
levisnteeshirt wrote:pinion angle ?
not sure? go on, school me on why, how that would make inconsistent 60's etc..
NO, sorry. Try the tire approach, less air more air. Wheelie bar adjust. It has worked for many years. I always wonder what the hell those guys are doing under the car after every pass with the pinion angle? :?:

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 9:47 pm
by n5ifi
This scope of this question is much to vast to answer completely in this forum.
There are way to many unknowns/variables at this point to answer the question.
The driver, track, car, weather are things that could be issues with consistency.
It appears you think the car should stay the same ET every pass no matter what.

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 10:15 pm
by raynorshine
n5ifi wrote:This scope of this question is much to vast to answer completely in this forum.
There are way to many unknowns/variables at this point to answer the question.
The driver, track, car, weather are things that could be issues with consistency.
It appears you think the car should stay the same ET every pass no matter what.
-agree, many unknowns and varibles
-driver, track, car, weather are issues, agreed again

-yes, there are cars that DO NOT change ET, every pass no matter what

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 10:25 pm
by rfoll
When I bracket raced frequently, the single thing that made me more consistent was using a fresh air supply to feed the motor. The later rounds have you hot lapping the car, and the under hood temps skyrocket.

Re: more consistent 60's, ET's..?

Posted: Sat Oct 12, 2013 11:07 pm
by Strange Magic
pinion angle ?
Color of car?

Take .008 of main out. If it slows up, your moving in the right direction. If it doesn't slow up, take another .008 out. A tune up that leaves your ride with it's fastest passes will be inconsistent compared to the consistency it will have when adding some extra fuel.

Do not tune an alky engine as if your where tuning a gas engine.

2 battery's in the trunk is almost mandatory with most all Camaro's.
When I bracket raced frequently, the single thing that made me more consistent was using a fresh air supply to feed the motor.
Do the opposite when on alky. Do not seal the hood scoop off. Water grain changes in the air greatly affect the HP of an engine when it's on alky. Try to reduce the amount of fresh air as much as you can.

Re: more consistent 60's, ET's..?

Posted: Sun Oct 13, 2013 8:57 pm
by raynorshine
Strange Magic wrote:
pinion angle ?
Color of car?

Take .008 of main out. If it slows up, your moving in the right direction. If it doesn't slow up, take another .008 out. A tune up that leaves your ride with it's fastest passes will be inconsistent compared to the consistency it will have when adding some extra fuel.

Do not tune an alky engine as if your where tuning a gas engine.

2 battery's in the trunk is almost mandatory with most all Camaro's.
When I bracket raced frequently, the single thing that made me more consistent was using a fresh air supply to feed the motor.
Do the opposite when on alky. Do not seal the hood scoop off. Water grain changes in the air greatly affect the HP of an engine when it's on alky. Try to reduce the amount of fresh air as much as you can.
-color of car, Karmenrot
-yes, i have to play with the fuel delivery more, richer still! seems methanol needs to be crazy rich :shock:
-havent had time to play with the ignition timing, locked at 36*
-or with tire pressures
-or valve lash (.022")

-i haven't scaled the car lately...what kind of percentage should i be shooting for, front vs rear?

Re: more consistent 60's, ET's..?

Posted: Sun Oct 13, 2013 9:30 pm
by Strange Magic
39 degrees

Weight, scale. It doesn't really matter, there is not much you can do with that car. It is what it is. If it only has one battery, then get a second one in the trunk. You should be leaving with the front wheels 2.5 to 3 feet in the air each and every pass.

Re: more consistent 60's, ET's..?

Posted: Sun Oct 13, 2013 9:59 pm
by raynorshine
Strange Magic wrote:39 degrees

Weight, scale. It doesn't really matter, there is not much you can do with that car. It is what it is. If it only has one battery, then get a second one in the trunk. You should be leaving with the front wheels 2.5 to 3 feet in the air each and every pass.
-yes, only one battery in trunk...that's an easy fix and i like the extra comfort zone an another battery would provide..even tho i have very little electrical to operate
-not pulling the wheels presently, but i don't think it would take much to do it :lol:

-why 2.5 to 3 feet wheel pull? doesn't that slow you down? or what would be excessive?

Re: more consistent 60's, ET's..?

Posted: Sun Oct 13, 2013 10:16 pm
by Strange Magic
No, you will run faster and more consistent for that application you have. You have to get the front wheels up in the air good to plant, and keep the tires planted.

A 27 or 28 inch front tire and about 4 inches of front travel will help it as well.

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