Vibration in Driveline
10-28-2009, 11:20 PM
#1
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Vibration in Driveline Ok, so I just finished the 383 build and got everything in the car. I am taking the car tomorrow to get it aligned because I put a tubular K member in the car.
When the car is sitting still (it still hasn't seen the road yet) anything higher than 2000 RPMs the driveline starts vibrating. I can feel it in the WHOLE car, the seat, shifter, floorboard, EVERYTHING.
The rotating assembly was balanced by a reputable shop and nothing else was changed. Still running the same tranny, flywheel, pressure plate, clutch, balancer EVERYTHING.
Any help would be appreciated guys.
When the car is sitting still (it still hasn't seen the road yet) anything higher than 2000 RPMs the driveline starts vibrating. I can feel it in the WHOLE car, the seat, shifter, floorboard, EVERYTHING.
The rotating assembly was balanced by a reputable shop and nothing else was changed. Still running the same tranny, flywheel, pressure plate, clutch, balancer EVERYTHING.
Any help would be appreciated guys.
10-28-2009, 11:34 PM
#4
If the flywheel you have was setup for factory bottom end style balancing (with a weight in the flywheel) but they "zero balanced" the new rotating assembly, that would be your problem.
10-29-2009, 12:23 AM
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He said it does it with the car not moving so it's not the driveshaft/ujoints. It has to be something in front of the trans.
If the flywheel you have was setup for factory bottom end style balancing (with a weight in the flywheel) but they "zero balanced" the new rotating assembly, that would be your problem.
If the flywheel you have was setup for factory bottom end style balancing (with a weight in the flywheel) but they "zero balanced" the new rotating assembly, that would be your problem.
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10-29-2009, 12:29 AM
#8
You're totally right though, if it's not a balance issue it's a misfire. 100% sure you have the plug wires on the right opti terminals? 100% sure all plug wires are on the plugs and opti terminals fully? Just basic things to check that get overlooked sometimes.
10-29-2009, 01:27 AM
#10
the way it was, it was a STEADY shake, constant, there was no intermittancy to it. Also, no popping/etc like with a miss. Just feels like a washmachine throughout the car
10-29-2009, 03:33 AM
#11
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does the shake vary with rpm? I am also leaning towards the pulg wire issue as I have made this mistake myself at the end of a long install just trying to get everything buttoned up. I was surprised how well it actually idled with 1 and 3 plug wires reversed but any throttle input would cause similar symptoms.
10-29-2009, 09:04 AM
#13
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It only does it when idling. I don't think it would be a misfire though. I know all the wires on the plugs are right, unless the ones on the opti are wrong.
The builder told me that the motor was at TDC when I got it back. So I installed the opti like it should be and every 1/4 turn when I adjusted the valves was right so I'm positive that is fine. I guess I'll have to just check the wires going onto the opti.
The builder told me that the motor was at TDC when I got it back. So I installed the opti like it should be and every 1/4 turn when I adjusted the valves was right so I'm positive that is fine. I guess I'll have to just check the wires going onto the opti.
10-29-2009, 10:20 AM
#14
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Got a converter in? A bolt may be loose, or out. Also, check the mounts to the engine, may be off, or loose causing the engine to move some or go out of balance at the higher rpms. Just my ideas where to also look.
10-29-2009, 11:45 AM
#16
the thing is, the motor sits 100% still in the engine bay, it doesnt shake the slightest like you would think it would if it were out of balance. I suggested the motor mounts beacuse the "vibration" gets worse as rpms go up. but they're not solid mounts.
10-29-2009, 11:56 AM
#17
How big is the cam?
Did you change your motor mounts in this project?
Have you verified that plug wires 6/8 are not crossed?
Who tuned it?
Did you check for vacuum leaks?
Did you change your motor mounts in this project?
Have you verified that plug wires 6/8 are not crossed?
Who tuned it?
Did you check for vacuum leaks?
10-29-2009, 01:07 PM
#18
Cam IIRC is 236/242
motor mounts are the same as before, used a BMR tubular k-member, so the passenger side mount base is different now.
10-29-2009, 01:10 PM
#19
10-29-2009, 02:08 PM
#20
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Motor mounts are the same but base on driver side is different because of the BMR tubular k member.
I'll check the wires tonight but I know that the driver side is fine.
Car has not yet been tuned.
No, haven't checked for vacuum leaks.
One other thing that has been brought to my attention is that my coil wire was arching out on the water pump when I first tried to start it. I'm gonna replace that wire tonight if the plug wires are not crossed.