Real slow with 9"
Real slow with 9" How much will a 9" usually slow down a car? With a stock suspension, stock 10 bolt and a shity launch my car ran 12.666 @ 113mph w/ a 1.9 60'. Now I have a 9" with a detroit locker and 4.11's and a torque arm. Now it runs 13.3 @ 107 w/ a 2.0 60'. All it does now is wheel hop off the line. I was shifting at 6k and ran it to about 6300 in 4th. It was pretty hot the other day, but where did the rest of my ET do? My car seems to be running alot richer than it used to, it's never been tuned, but I don't see that effecting it that much either. So it has to be the 9"?
Teching In
Joined: Jul 2005
Posts: 11
Likes: 0
From: Boca Raton, FL
The type of rear in your car shouldn't change your ET. It's a "hard part", meaning, it's just a piece of steel with gears and bearings in it. Is the gear ratio the same? Has the pinion angle, shock location, type of spring/shock changed? The real question is, what else was changed when the rear was swapped?
I hadn't been to the track on the new torque arm setup until the other day, and that was also the first time out with the 9", and textralia clutch. It's possible the pinion angle has changed since I set it last, because I didn't check it again after I put the 9" in, my *** got lazy. But I still should have been trapping higher than 107, I think thats what I trapped bone stock in hot weather. It's probably caused by a few problems combined together, but I still think the 9" slowed me down some.
I scanned it last night to start tuning the car and it looks like I have knock retard in the higher rpms, but i can't be sure how much because I'm tuning the LTFT's right now and can't go WOT. I forgot until I saw that that a few weeks ago my car was throwing a knock sensor code int. looks like I'll be pulling the intake off to replace the rear sensor.
