I've been wanting to do some no throttle stop/delay box index racing with the car. I tested this style racing a couple weeks ago and had a blast & lucked out with a win. It paid some decent money, but that's not what I was there for. It was a 6.0 index on .500 pro-light.

While the popular faster indexes are the 5.30, 5.35 & 5.80 classes on a .400 pro-light. I hope to test the waters in the 5.80 index in early Nov. at Famosa, CA. While my current tune has enough to run under that index. The .400 tree will probably be the biggest hurdle. The best I could do when the car was NA & set-up for this tree was an .060-.070 light.

If testing the waters, go well in early Nov. I might try the 5.30 indexes & I'll have to lean on the motor a little harder (more boost). Another issue in the 5.30 indexes is some of them require a spec tire. You can run a 28x10.5 bias slick or a 275/60 DOT drag radial. The latter is probably what I would use. Both tires will have 2" less diameter than I run but shouldn't be an issue.

For the .400 tree, I'll set-up the suspension for it & leave off more boost at the hit. I only leave on 3 lbs. now leaving at 3400 rpm. We tested the car 4400 & got 7 lbs. but don't know if I can hook it, especially with a smaller tire.

I'm not looking to give up bracket racing, just supplement with 4-5 five index races a year. The 5.30 index is in late Nov. & pays 7K, not too shabby.

Let me know what you guys think.

2BKING

quote:

Originally posted by B KING:
Another issue in the 5.30 indexes is some of them require a spec tire. You can run a 28x10.5 bias slick or a 275/60 DOT drag radial. The latter is probably what I would use.

Also, the 5.30 indexes don't provide times/slips. Most, if not all use a Dragy & my son ensured that I have one as a gift for my birthday.

2BKING

The index racing is a different game than bracket racing and lots of fun. New Challenge. I really enjoy the heads up racing feel. It required a lot of testing for me, working on car and some racing to get good at it. Many are using a restrictor plate set up but I do not think that would work with your combination and it did not work with mine. Yes, slower ETs are harder to cut a good light on .400 Pro Tree, car does not move out of beams as quick. Also many carbs are too fat and will not bring up RPM quick enough to cut a good consistent light on pro tree. If your injection or carb is too fat on the hit it will more roll up in RPM than snap up. I really struggled with one car trying to slow it down to 5.50 class with a carb.
Looser converter and more RPM may help with reaction times. Get the motor higher up in power band to get it to launch harder.
I tried with no chip in the 2 step and that was worse, felt like it was just driving out and transbrake did not seem to hit as hard and reaction times were slow. I think you need to have 2 step approx 2,000 RPM below stall and stall should be high enough to get motor in sweet spot and move car.

Curly, thanks for giving my brain a poke!

My 1st priority will be working on reacting/setting up for the .400 light. 2nd is leaving with more rpm/boost & that should help with the reactions & a quicker ET.

I currently leave at 3400 rpm & 3 lbs. boost & have never tried higher on the track. We have checked the boost at 4200 & 4400 rpm & get 6-7 lbs. boost. I don't know if my small tires can leave on that, but we're going to try & leave at higher rpm's. Our converter flashes to about 5600 rpm at a 3400 rpm launch. The fallback rpm on the shift is 6100 rpm.

2BKING

We have a fair amount of 6.0 stuff locally and i get to 6.0 by shifting on time. Not sure how it would work with your combo. The tree is not a problem. I run 15 to 20 delay.

ep

quote:

Originally posted by pauley:
We have a fair amount of 6.0 stuff locally and i get to 6.0 by shifting on time. Not sure how it would work with your combo. The tree is not a problem. I run 15 to 20 delay.

ep

The 6.0 index was a last-minute race just to test the waters. My car set-up for .500 full tree & it worked well on a .500 pro tree. The only thing I did differently was use my short travel transbrake switch vs. the long travel switch.

I'm not sure if you bracket race your car, but that's what I primarily do. I've always had to change my front suspension set-up & launch rpm for the .400 tree. I don't know how less travel up front & increased launch rpm (more boost) is going to work with my small radial tires. I guess I'm fixing to find out next month.

As for slowing to a 5.80 or even a 6.0 index. I do shift on time but have been using a launch retard to slow the car. Not sure what's the best way of doing it.

2BKING