Twisted Crank?
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
The driveshaft appears to be fine, and the car would vibrate in neutral or when in gear always,
Well, to recap,,,,
I drove to the dyno, car was fine, did 4 dyno runs and the car was fine up to 6200rpm, drove home from the dyno, car was fine, drove to the track, car was fine, staged in the burnout box, car was fine, dumped the clutch at @2500rpm, car began to vibrate violently when I would rev the car.....drove home, car was fine until I revved it up to 3k + rpm, went home and pulled the clutch and had the Flywheel and clutch re-checked for balance, they were spot on,,,,, put then back on and the vibe was still there from @ 3krpm upward
After that, and up until I pulled the engine, the car ran great until I would get to @ 2800rom, then from 2800 up the car would vibrate as a I accelerated and get worse up to 6k rpm.
I have replaced or inspected every possible engine part on the car, fuel injectors, distributor, wiring, ecm, heads, fuel pump, push rods, damper, accessories, and the vibe was still there......
then I pulled the crank and had it checked and it was out of balance by 30-grams according to the machine shop that originally balanced it, same presure plate, sem damper same flywheel......
the simple answer is that the crank is messed up, nothing more or less, it was fine before the drag run, then it wasn't after the drag run.
I have not had any time to look at the old crank, been buying some new parts and sizing a new cam....
Bought new Eagle forged H-beam rods and Eagle forged crank...,, spring is on the way and I'm a happy camper!
Well, to recap,,,,
I drove to the dyno, car was fine, did 4 dyno runs and the car was fine up to 6200rpm, drove home from the dyno, car was fine, drove to the track, car was fine, staged in the burnout box, car was fine, dumped the clutch at @2500rpm, car began to vibrate violently when I would rev the car.....drove home, car was fine until I revved it up to 3k + rpm, went home and pulled the clutch and had the Flywheel and clutch re-checked for balance, they were spot on,,,,, put then back on and the vibe was still there from @ 3krpm upward
After that, and up until I pulled the engine, the car ran great until I would get to @ 2800rom, then from 2800 up the car would vibrate as a I accelerated and get worse up to 6k rpm.
I have replaced or inspected every possible engine part on the car, fuel injectors, distributor, wiring, ecm, heads, fuel pump, push rods, damper, accessories, and the vibe was still there......
then I pulled the crank and had it checked and it was out of balance by 30-grams according to the machine shop that originally balanced it, same presure plate, sem damper same flywheel......
the simple answer is that the crank is messed up, nothing more or less, it was fine before the drag run, then it wasn't after the drag run.
I have not had any time to look at the old crank, been buying some new parts and sizing a new cam....
Bought new Eagle forged H-beam rods and Eagle forged crank...,, spring is on the way and I'm a happy camper!
