Okay, I've decided to stroke my 355 to a 383. First I have a stock 1988 GTA flexplate and balancer. My crank I purchased is "externally" balanced 1pc rear seal. Can I use the following on my current flexplate?:
http://www.speedwaymotors.com/xq/asp...qx/product.htm
I found this on a post here.

Also, what size harmonic balancer should I use? The 8" or 6" balancer?

Basically I'm hoping to get some expertise from people here who have done the same 383 setup I'm attempting.

 

If your rotating assembly was balanced with that harmonic balancer and that flex plate you cant swap em without having it re-balanced. Thats what ive always practiced and have been told.

 

No, that's for a 2-piece rear main seal crank (see the reference to 55-86).

Use the one that lines up with your timing tab.

 

Not true as long as the damper and flex plate were not modified during the balancing process.