[Keesling]

AAAlright let me make this simpler to read.

Bought wrecked 96 trans am running perfectly
Installed lt1 into my camaro pic in sig
After installing the motor I noticed it shook at certain rpm more than others.
The car had an electric water pump on it so I kept that
I also replaced the clutch when I swapped it
Did a bunch of other things in sig I've even modded it since installing and the vibration is still there.
But keep in mind I removed the pressure plate and disc and only flywheel the engine still has that weird rotating vibration
So I messed with the balancer rotating the hub 90 degrees and trying it.
It was still there. I even ran it without the balancer on and only the hub still there.
After that I decided to get the flywheel checked out by a machine shop.
Even discussed with them about lt1's and that it's externally balanced on the rear.
They balanced the flywheel and pressure plate together and sprayed some paint to mark the pressure plate orientation.

However now with it apart I'm unsure what they did as there are many drilled holes and even two in the molded weight on the back.
From what I have read there isn't supposed to be alot of drilling at all.
So that can't be right.
Is my flywheel out of balance? or what?
Should I buy a flywheel?
Or Is my crank bent or something?
Only reason I replaced the clutch was that the pedal felt high but come to find out that is the way it is. Lesson learned.
Now why would it still do it without the clutch, before and after balancing.

I guess I will try a flywheel then a balancer and then motor mounts.
If none of those then I guess it's internal ?

 

[guppymech]

Try getting a new stock flywheel from like advance auto. Your TO bearing is no good now with that tang broke off, stupid pull type clutch has the TO bearing spinning with the PP. It's important to make sure that the flywheel sits flush on the crank flange with no burrs or debris to make the flywheel sit crooked. You seem like you've covered all the bases, I would look at a new flywheel.
One more thing try not to run the engine too much with it vibrating, it can ruin the bearings. A buddy of mine was breaking in a new cam on a new engine and his flywheel was balanced wrong, he was out of the car and didn't realize the engine was misbalanced until it was too late.

 

[Keesling]

Yes I think That is my next move.
About not running it though It has been driven alot and not easy either and the oil never had metal in it except recently when I did my cam but that was lifters rockers and pushrods wearing in too. Now no metal this last oil change and oil pressure has always been the same? :dontknow:

So I ordered a flywheel from rock auto for 92 bucks shipped, ac delco too.
Hopefully it rids of this vibration.
Pic of the flywheel i currently have
look at all the drill holes. (surely it isn't balanced right)

we will see