Need some ideas. Helping a friend (without web access) set up his car for a very popular heads up index class drag racing down here in Alabama.

They run on a .400 pro tree with really only 3 rules (other than safety equipment)

1. 3000 lbs minimum
2. mufflers
3. 10.5 slicks (or 10.5W dot's)

1/8 mile only, classes are 8.00, 7.00, 6.20, 5.70.

The car is a 69 Mach 1, with a 460. It has mild hyd cam .585/.585 240/250 @.050. .030 TRW mini-domes (~10.5:1) home ported DOVE heads, Crites headers, Offy Port-O-Sonic single plane, 850 dp, recurved Duraspark w MSD 6AL, 1.73 roller rockers, all the usual stuff. Trans is a C-6, fully rollerized, lightened drum, etc, with a transbrake, 4500 stall 10" converter. 28X10.5 MT slicks, 4.56 geared 9" with Moser 31 splines and full spool. Car has ladder bars/coil overs and mini-tubs. Weighs 3180 w driver.

The car currently runs 7.15-.20 in the cool, 7.20-25 in the heat mph is ~95. He has a nitrous system that he used to run in this car when it had a 351C. (7.20's w/a 150 shot). The car is still plumbed for it. 1/2 fuel line, Holley black pump for the motor, 3/8 line and a blue pump for the bottle.

He wants to install the nitrous and put just enough of a shot to run 7.00. He could go after the 6.20 (my idea), but he figures that would also mean a cam change.

How much would it take to drop the ET to to 7.00? 75? 125?

Also, he has a good Dedenbear crossover style delay box. I figure that there must be some way to use this box as a timer for the nitrous system (he doesn't use it bracket racing). The box can be set anywhere from 0.001 to 99.999 seconds. Would like to maybe use a bigger shot like a 150, but only turn it on at half track or so. Just need to know how to wire it. Normally open or closed relays? Run it off the Two Step? How? That way it will still run the 7.00, but run a big mph. Harder for the opponent to judge.

Ideas? Suggestions?

Thanks,

I'm not into bracket racing, I just like going as fast as i can on a casual basis in a streetable car. Nitrous allows me to blast a pump gas compression car around the roads off the bottle, then switch to race fuel and open the bottle at the track for maximum et's.

It sounds like this guy wants to run consistent 7.0's. Nitrous isn't really the best way to be consistent. It's just one more variable to account for. Yes, it IS fun, and if he wants to take a shot at the 6.20's, nitrous will allow him to do that.

If he really wants to be competitive (consistent), however, his best bet is to run off the bottle.

I agree that the converter sounds a bit loose. His car would probably pick up with the Stealth and a slightly tighter converter. He might get there with the stealth alone.

Good Luck!

quote:

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Originally posted by n2oMike:
It just depends on what he wants to do...

If he really wants to be competitive (consistent), however, his best bet is to run off the bottle.

Good Luck!

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Isn't that the truth, can you imagine keeping the bottle pressure the same for several rounds during eliminations. You'd need several bottles, bottle warmers, coolers, and you wouldn't have any time to concentrate on racing.

I'll try to steer him away from the bottle. (Maybe put it on mine and see if can run some 6.0's ,).

I have said all along that it needed more cam. The hyd grind in there now is something you would drive to the grocery store. It was one of those deals where he got a new in the box cam for next to nothing on a trade. Does anybody have a recommendation for a good solid flat tappet cam? The general car specs are at the top of this thread. When we put the engine together I checked the piston to valve clearance. It can handle up to about .630 lift before it gets dangerous.

The converter actually works well in the car. It had a 10" 34-3500 stall in it. We swapped in the 4500 (flash is 4500) and it picked up .15 in the 1/8 and .08 in the 60 ft with no other changes. BTW, he shifts it at 6000, crosses the 1/8 mile in 3rd at 5500.

Thanks,