http://www.slantsix.org/forum/viewtopic.php?t=27754
I am having some lean spikes as discussed in the above thread and wanted to split up the track launching technics that may avoid the above problem all together.

Does it seem plasiable to hold the car at the line hard enough to get the vacuum secondaries to open some without the car moving. Maybe 1/2 throttle and on green hit the gas from 1/2 to full throttle and let the brake go at the last moment. Without drag tires my car would simple go up in smoke, but I with now be running them and this should no longer be a problem. (traction) My thinking is that the two leak spike would have passed before the car even moved and therefor not count against me. Or with it still bog?
I kind of like the idea of coming off idle and using the engine momentum timed just right to launch me out of the hole at green. Again with a drag tires, otherwise up in smoke again.

The tires are here yet otherwise I would have tested this theory already.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

You don't suppose there really any great chance of breaking the 8 1/4 rear in this car with any of these launch types is there? I will be running 235-60-15 BFG drag radials with the 3.55 rear and Auburn posi)

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

You shouldn't be able to get the secondaries to open with the car at a standstill unless you have a really high stall converter and maybe a transbrake.

I doubt you'll break the 8 1/4 with an automatic.

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Joshua

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

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Juan Ignacio Caino

Please use e-mail button istead of PM'ing. I do log in sometimes but I'll be answering quicker thru e-mail.

I've had carbs in the past where I could not get out the flat spot on a launch. This technique worked: Try a slight load on the convertor and a real fast double pump on the accelerator pedal and staying at full throttle on the second pump. Sounds goofy but has worked. Usually on thermoquads where the throttle shafts are worn real bad and there is a vacuum leak.

Sorry I can't give some help with your hesitation problem but I can give you some other advice based on what you said above...

If you wait for the green bulb to light you have already lost .
I leave on the last yellow. Because my Dart is so slow to react I leave when it glows. On my brothers muskrat I leave when the bulb dims because it leaves so good. You just need to find your sweet spot, even with a hesatation you should be able to cut a good light in theory.

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Chris'
Autobody
Restoration
Service

I am also looking for a better launch technique. Is there any concern with hurting the 904 and 7 1/4 by powerbraking with a relatively stock slant and street tires?

You mean you initiate launch on the last yellow. If you leave on the last yellow you lose. (red light )

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

No, it actually starts moving as the amber dims. My Dart is that slow to roll through the lights!!!! My 60' is about 2.6 .
That is why I said you will have to find what your car wants to leave at.

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Chris'
Autobody
Restoration
Service

Watch how you stage too. Shallow or deep. This can affect your RT as well.

I deep stage, I stage right as soon as the pre-stage light flickers off, Then leave right about at the very middle of the last yellow. It gets me .000 to .040 lights every time. Although, my car does only get 2.9 60ft times.

In my 70 Nova though, I stage very shallow. As soon as the stage light flickers on. then I leave at right about the center of the last yellow. I get .000 to .040 lights that way all the time, but I also red light more with the Nova than with the Dart. I get 2.0 60ft times with the Nova.

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1963 Dodge Dart -225 Slant 6, 904, 2.76's, 18.84 @ 73
1970 Nova 12.53@108
1970 Bug 15.38@87