swap out the 250 with 302 and C4 from another project where it ran fine. Now there is a vibration. Seems to be related to the load in the car (got worse when I gassed up). Also vibrates when popped into neutral when the engine is revved to around 3k. I'm starting to think I have two problems. The driveshaft is custom made by a driveshaft specialty shop. I checked the run out and it was good. I've searched on this forum and others have mentioned the same problems but didn't find anyone mentioning what fixed their problem. thanks ps tried to download pictures but they are too big.
the flexplate is an aftermarket SFI rated Chinese flexplate. this is the same unit from the other car I pulled the motor from where it worked fine. Now, the other car had a different motor mount system. The motor was in a 32 roadster and we were using front mounts with little pads. I'm thinking of buying another torque converter.
take it out for a drive... get it up to where it vibrates... shut the engine down and in neutral.. does the vibration go away.. if so.. it is possibly engine related.. if it is still there it is wheels, or drive shaft.. etc good luck.. and let us know when you find it also... maybe the balance weight came off the driveshaft?
Changed intake and older carburetor. Feels like it's running on 6 cylinders. changed plug wires and plugs, same. Bought new carb today... runs great, but still vibrates at speed. I believe there are two problems. Phil
Changed transmission mount, the old one was taller and had a metal brace built in. I believe the vibration is still there, but is about 50% less noticable. Have new motor mounts to try next.
Was the drive shaft balanced..........When I made mine, I installed 2 tubes of grease. That has been 4 years ago and still no sign of leakage......it worked for me
if you replace the rubber mounts and the vibration goes away, it is still there.. you just cant feel or hear it because of the mounts.. dont hide the vibration.. find it.. it could be a lot more expensive if you let it go
Normal factory frame stands and aftermarket replacement motor mounts. The new motor mounts I recently purchased, but have not installed yet, have this kind of rivet running through it. I might remove said rivet before installing. Phil
don't do that. If you remove that pin your mount may move in directions you don't want it to unless you replace it with a grade 8 bolt and nut.
