A friends car runs 6.50 in the eight and we are trying to get him to run in the 7.0 heads up class. He has a 496 ci G-body with a Dominator. I was wondering about how much would a 750 DP Holley slow it down. We both run E85. How much would the smaller carb slow it down from it's 6.50 time.

It likely won't at all....try a different shift point, add some weight to the car, pull some timing....

shift .30 out and you will lose .40 in et.
you can play with weight to get the rest. also you can move your shift point once you get close to pick up or slow down to stay at 7.0 or hold some. meaning .27 out would be 7.03 ant .33 out would be 6.97.

ep

I think smaller carb would slow it down but why not use like ET Genie or something similar?
With that in a few passes you should be close and then fine tune it to weather.
I have not used one but I think that is what I would do then you would have the ability to adjust to weather. Do not know what brand I would use.

What Pauley said

Thanks, guys

I have found that shifting early like that will tend to be 1 to 1 on time vs et. So for every .01 you move time = .01 in et

ep-to a point naturally

quote:

Originally posted by Honkytonk HERO:
A friends car runs 6.50 in the eight and we are trying to get him to run in the 7.0 heads up class. He has a 496 ci G-body with a Dominator. I was wondering about how much would a 750 DP Holley slow it down. We both run E85. How much would the smaller carb slow it down from it's 6.50 time.

So you have a 3550 lb BBC G body with a E 85 Dominator carb? You wanna know how much slower a 4150 E 85 carb would be on the 700hp BBC pulling the 3550 lb G body? Correct?

Maybe a tenth.

I agree shift it early, I wouldn't change the carb, that would require burning additional fuel getting the tune right. I'd shift early, If I didn't have timers needed to shift early I'd throw ballast in the trunk to slow it down. I'm sure it's a 500 sportsman tree , so the car reacting slow due to the additional weight, won't matter.