i just put a motor i picked up in and drove it for a little bit
but at around 4000 rpms and up there is a bad vibration the guy i got it from said that the motor was internally balanced so i got my clutch/flywheel assembly neutrally balanced for it but this vib is makin me crazy
whadda yall think it could be?
if ya need any more info on it just ask

 

took it for a good drive yesterday and you can kinda feel the vib through the whole rpm range
the car pulls real hard up to 6000+ but the vibration still freaks me out
one of my buds say that it might just be the power of the engine but it kinda feels like somethins outta balance and its not speed related so its befor the tranny most likly \any suggestions?

 

Will it vibrate if you rev it on meutral? What kind of mounts you are using?

 

could be a bad motor or tranny mount. if it's vibrating when you'r accelerating than its probably a bad mount. what mounts do you have on there?? get ones that decrease the vibration. that is why a lot of people when they get new tranny's get better mounts

 

ive got stock ish rubber mounts for both
so they should be better for dampining vibration
and it does do it while its in neutral
i mean the car feels strong as hell but i guess it could be motor mounts
but thanks for the replies

 

It's definitely not "normal" due to the power it's making. Lots of high horsepower cars run smoothly. Mine had a bad vibration too and it was a internal/external balance issue, but since yours is internally balanced (mine was not) and the flywheel was neutral balanced that shouldn't be your issue. We ending up pulling my trans and letting it run that way to isolate it to the engine side first....have you tried that?

I know you said it does that in neutral, but is that while stopped and reving it, or going down the road? I ask because driveshaft orientation has been known to cause similar issues.

 

Put a stock flywheel on it and see if it's internal balanced.
The other way is to tear it down and take it to the shop.