What is the H.P. difference in a 9" & a quickchange?

[Cooter Davenport]

Can anyone tell me how much horsepower a quick-change rearend looses over a 9" grand-national rearend?

[washeduptoo]

Do a search on that subject, seems like they said 5-15 loss but not sure. Best of luck.

[jsf74]

not enough to worry about espically on a slick track.

[RACEMAN]

It seems like a few guys have access to a chassis dyno. Run a series of tests, (without 3 times, with 3 times and then without 3 times). Should be able to have a good idea of what the change is. Make sure you allow for some error in each series. (The second without 3 times is to make sure the car returns to baseline.)

[cozmo28]

would it be enough to worry about if you were running a 602 crate motor

[jsf74]

Youre gonna need all u can get from a 602. U trying to run this in a ump mod?

[cozmo28]

no car is a ump mod but running limited mod on hoosier a's similar to b mod only still on 4 bar