Vibration in new engine after 4000 RPM???

Ackbar00 · 06-28-2004, 05:32 AM

Vibration in new engine after 4000 RPM???

Just got the new engine in the car and I am getting a pretty good vibration after 4000 RPM and up. I have tested this with the car sitting still, so I do not belive that it is in the drivetrain. Using a Stock Balancer on the new 306. Just had the flywheel resurfaced. Made sure all the obvoius bolts were tight. My brother thinks this could be due to exhaust resonance from the downpipe (I am running it open right were it curves to the back down the firewall). Was not doing this before the motor swap. Exact same combo as before, except it now has a F-Cam. Any Ideas???

Ackbar00 · 06-30-2004, 11:58 AM

No ideas eh?

LX5liter · 07-01-2004, 08:58 AM

Did you rebuild your old motor or get a different one? I'm just thinking maybe the motor was balanced for 28oz instead of the factory 50oz. You may have damaged your stock balancer pulling it off as well. I think thats where I'd start.

06-28-2004, 05:32 AM	#1
Ackbar00 Rebel Fleet Commander Join Date: Oct 2001 Location: Huber Heights, OH Posts: 1,003	Vibration in new engine after 4000 RPM??? Vibration in new engine after 4000 RPM??? Just got the new engine in the car and I am getting a pretty good vibration after 4000 RPM and up. I have tested this with the car sitting still, so I do not belive that it is in the drivetrain. Using a Stock Balancer on the new 306. Just had the flywheel resurfaced. Made sure all the obvoius bolts were tight. My brother thinks this could be due to exhaust resonance from the downpipe (I am running it open right were it curves to the back down the firewall). Was not doing this before the motor swap. Exact same combo as before, except it now has a F-Cam. Any Ideas??? __________________ 1993 Mustang GT, PTK w/ T-64 - My Cardomain Webpage 11.25@123.5 on only 8 psi. 10.84@121 on only 1 headgasket "The Truth is, Your the Weak, and I am the Tyranny of Evil Men!"

06-30-2004, 11:58 AM	#2
Ackbar00 Rebel Fleet Commander Join Date: Oct 2001 Location: Huber Heights, OH Posts: 1,003	No ideas eh? __________________ 1993 Mustang GT, PTK w/ T-64 - My Cardomain Webpage 11.25@123.5 on only 8 psi. 10.84@121 on only 1 headgasket "The Truth is, Your the Weak, and I am the Tyranny of Evil Men!"

07-01-2004, 08:58 AM	#3
LX5liter dude5l Join Date: May 2001 Location: Grande Prairie, Alberta, Canada Posts: 603	Did you rebuild your old motor or get a different one? I'm just thinking maybe the motor was balanced for 28oz instead of the factory 50oz. You may have damaged your stock balancer pulling it off as well. I think thats where I'd start. __________________ Good luck! Brad R. 1992 L.X. 5.0 coupe MODS: A few little bolt ons New Best time ...11.60 @ 128 mph @ 2000+ ft altitude. Rice Haters Club member #39 Users rides #2542

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