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09-22-2014, 08:02 AM | #11 |
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Re: Problem cutting a light
All these ideas are great.
Mark, the harder I leave on the starting line, the harder the car lifts the front and hits the rear tire. When the front of the car lifts more, the slower the car reacts. The converter works great. I cannot see it being that because of how consistent it is. Gump, I have thought about taller tires for the rear. I have non to try at the moment. I have 50psi in the front tires trying to make them the least amount of contact with the ground. They are 165/70/r15 volkswagon tires. Not race front runners. I have tried bumping in 2 bumps at the line. It kills the et and made the lights drop to .590- .600 range. As far as the efi having a flat spot. I have tried another chip in the ecm from another tuner and it slowed the car down and the reaction got slower. I Have cut some .530 lights with the car, but I was anticipating the light. All these Ideas are great. What about torque arm angle? Do I have too much front end travel? Thanks AAron |
09-22-2014, 08:25 PM | #12 |
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Re: Problem cutting a light
Cheap way out: Leave at a different spot on the tree?
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09-22-2014, 08:39 PM | #13 |
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Re: Problem cutting a light
Front end travel is usually a very big amount of change in RT.....
It is in a first generation F-Body....and more than a tenth is up there in those cars. Maybe not as much in a later model with coil over type front end.... The problem is always limiting travel at some point will hurt weight transfer and traction.... Shorter front tires.....less front end travel....raise your starting line rpm as much as possible...... What do you want good RT's or the fastest ET's....One does not go with the other in a car like this......that's why people deep staged.....Speeds up RT's but kills ET's....
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Rich Biebel S/C 1479 |
09-22-2014, 11:31 PM | #14 |
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Re: Problem cutting a light
A friend just had a VW radial come apart on him this past weekend, almost flipped car. His were pretty new, i took my old ones off and I'm glad I did
You want shorter front tires for a faster reaction time and less rollout.. I've had RT woes and biggest improvement i saw once I worked tuneup and suspension was converter. Your RT are quite a way from fine tuning something if they're in the .6's. It does sound like a stumble or delay in the engine to be that late. My 3rd gen has a lot of frt. end travel but I can still get it to react good . Last edited by Eman; 09-22-2014 at 11:37 PM. |
09-23-2014, 08:12 AM | #15 |
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Re: Problem cutting a light
What gear do you have in the rear end?
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Mike Pearson 2485 SS |
09-23-2014, 09:41 AM | #16 |
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Re: Problem cutting a light
Part of the reaction time equation is your vehicles rolling resistance (RR). The less (RR) the faster the car will move from a dead stop. Try increasing the rear tire pressures in 1 pound increments to see if that helps with your RT. If it does, keep increasing the tire pressure until the improvement stops or you get tire spin. Because of your consistancy with your reaction times in the .671 area, I don't think you have a converter issue either.
On another note what rear tire do you run? I am not familiar with P/S rules regarding tires. Your 60 foot time seem a bit slow. I run 1.60 60 foot times but our car weighs almost 4300 lbs with driver. My guess you are at around 3,500 lbs. You get this RT issue straightened out, you are going to have a killer vehicle/driver combo. Good Luck.
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Nelson Kowal Stock 345 Last edited by njk53; 09-23-2014 at 09:58 AM. |
09-23-2014, 09:48 AM | #17 |
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Re: Problem cutting a light
have you ever driven another car? 670 is out to lunch I would be 570 in a slow car had to deep stage would be 520 then?
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09-23-2014, 01:54 PM | #18 |
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Re: Problem cutting a light
The car weighs 3680. I used to race super street for 20 years. Then took a break in 2008 and just returned to racing the beginning of this year. I will try the rear tire air pressure this wed. Rear gear is a 4.56.
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09-23-2014, 02:16 PM | #19 |
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Re: Problem cutting a light
I would think some more gear would help. That's a heavy ride. Are you still trying to drive this car on the street. I would think a 5.13 would be better
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Mike Pearson 2485 SS |
09-23-2014, 02:27 PM | #20 |
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Re: Problem cutting a light
Is there any play in the ends of or slack in the throttle cable?
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Chris Bowman The Mountain State Mustang 1984 Mustang GT350 |
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