A ran at the bracket races at the Cruise In at Bowling Green...

The dewpoint was in the upper 50's with a temperature in the lower 70's. The altidude is about 550 feet in BG.

The car hooked good with no spin at all (reviewed the videos) and my mph was some of the best I've ever run with the new setup.. However, the 60' time was about .15 slower than what I usually run in Florida... My best 60' time was on my first pass in approx. 76 degrees. The 60' times were: 1.613, 1.682 and 1.684.

In Bradenton (Florida, 5 feet above sea level) I even ran a 1.560 in about 86 degrees with a dewpoint in the 70's . My mph on that pass was only 117.5 mph.

The mph in BG was between 119.69 and 120.01 and about 97 mph in the 1/8 mile but my 60' times were bad...

What could cause the 60' times to be that bad?? Looking at the mph, my power seemed to be good

 

I'm pretty sure the track was getting worse. I was never able to duplicate my first run despite temperatures dropping and feeling like I was doing better. On a plus note I managed to make it to the second-to-last tier of the eliminations before redlighting. Luck was definitely on my side, but I did make .052 and .060 lights that night. Had alot of fun with you guys.

-Chris

 

one thing about a race thrack is if it gets too hot it gets slick. Just like if it gets too cold. My guess is that with the sun beating down on it the track just got greasy. Part of racing. Play with your setup..shocks, tires preasure, etc...and tune the car back in. One thing you could try is take a pound or 2 out of the tires. You will be amazed at what even just 1 lbs can do. If you have adjustable shocks...soften em up, it will take the "shock" out of the suspension and will help the tires hook on a sllick track. Thats part of the fun of drag racing..adjusting to different conditions. Another thing that can affect traction are bald spots in the groove. Was this a corvette thing..if so alot of cars with the same wheel base are running and will develop a bald spot quickly. When we run f-body only events I actually line up alittle out of the grove to get on a part of the track everyone isn't using.

Just a few things to consider.

Tim

 

Traction was not an issue.. I have my runs on video and there was no spin.. There must've been another reason... Maybe the reason was my lower tire pressure.. Ran 14 psi instead of 15...

 

Dang Olivier, you sure do get around in that thing! One week your at this track, next week you're at that track...

 

Yeah... 5 track visits in 6 weeks

Already have approx. 30 passes on the new combo..

 

I'm surprised you had probs with your 60' there. I bet you are getting more and more consistant. Have you used that trans brake yet?

 

Didn't use the transbrake yet.. I think that it's smarter to use it in combination with a 2 stage rev limiter so that I can keep the pedal to the floor...

 

Sounds like you really are going all race/no street on your car. I would consider a trans brake, but the el cheapo stall I bought had warnings not to use one. Says it will create too much heat and burn up the tranny. Also there's the weak stock rear, and this, and that...
Anyway, I'm about to embark on a new career and if it works out like I think, I should be able to weasel more vette money away from my wife. If so, I'll be asking you a lot more questions!

 

How many runs you have on the tires? You might try swapping them from side to side to see if they hook a little better. Often they can hook intitially very good, then as the weight transfer goes away, they can slip a little. Bet those killer 60's were when they were new! I know the best mine ever does is when they are brand new. 50 runs later even though there is lots of rubber left, they don't hook as well.

Some shock tuning can help here. For an automatic car like yours I'd remove the snubbers under front control arms and let them have some more travel. Put shocks on 90/10, then try some adjustable shocks on rear to help control rate of transfer and unloading.

Gotta get that brake working..but don't expect too much. Some cars slow down using a brake. They often do better with coming out letting converter flash higher and multiplying TQ better. You can often send converters back to most race builders for one free "stall change". There is a LOT to converter science way past stall. There are changes that will effect how it transistions from full stall, to how much it hits tires, recovers on shifts, to slippage etc. I've seen cars gain .3-.4 with a converter change that had same stall speed! A motor dyno sheet is a great tool to have when they design a converter for you.

If you can get that sucker to hold in low gear, your 60's and 1/8th mile times will likely improve drastically.


JIM

 

Only have about 20 passes on the tires.. They are 90%.. Anyway.. traction was NOT an issue.. Dead hook on all runs.. I ran my front shocks at 80/20.. Hardly have any movement in the rear due to my 550 lbs/inch rear composite spring.. My converter is a 4500 stall speed converter.. That should be about right for my cam..