mrseven

Ok, getting ready to do the T56 swap, and I'm not sure what I need to do about the flywheel balancing. The afrashteh.com swap guide says to balance the new flywheel the same as the flexplate, but the guy I talked to says flexplates don't come balanced.

So I have a brand new SLP billet steel flywheel to put on a stock engine (minor bolt-ons). I don't want to take a chance of creating more vibration than there already is. Is it safe to bolt on straight out of the box? Can someone straighten this out for me please? Hopefully in the process saving me extra work, because I have no other transportation to a shop for balancing once the flexplate is out.

Thanks!

Kevin97ss

I use the SLP flywheel, but didn't do an A4 to M6 conversion. The FW was a direct bolt on with no need to balance. I called SLP and they assured me no rebalance was needed and they were correct. BUT I cant say for sure if it would be the same situation swapping from an auto. I would suggest calling SLP to see what they say. I think but am unsure that all LT1's are internally balanced and the flywheel and flexplate are zero balanced.

Injuneer

The stock LT1 is externally balanced, using a weight on the flywheel or flexplate. I went the other way.... T56 to TH400.

You need a flywheel with the correct weight on it. If the engine is stock, the weight is known.

Kevin97ss

Hi Fred, thanks for the correction, like I said I was not sure.

So then changing from a flexplate to a flywheel should not be an issue balance wise as long as the short block is still stock?

mrseven

Engine internals are all stock. Happen to know what that weight is? Then I can just take it to a machine shop and have them balance it.

mrseven

Well, I called SLP today, and they said the flywheel I bought from them should just bolt on, it's neutrally balanced. When I get the flexplate off I'll check for any external weights or something, but as of now I'm just gonna throw the thing on.

mrseven

Scratch what I said before. After a lot of research, I learned that a neutral balance flywheel is NOT GOOD for an externally balanced engine! (go figure ) Anyway, I talked to a guy at an auto machine shop, and he said it wasn't possible to balance my aftermarket FW the same as a stocker, even with both in hand.

But luckily I had a stock FW sitting in a box somewhere, so I'm just gonna resurface it and put it on. Just gonna sell the SLP one now.

Injuneer

What part of my original post did you not believe? Its common sense, once you understand that the engine is externally balanced.