I'm on jegs looking at rotating assemblies and their are a few differences that I'm not sure what they mean. What is the difference between 1pc Rear Main Seal and 2pc Rear Main Seal? Internally and externally balanced? And what do they mean when they say Factory Style (Internal Front, External Rear)?

Heres the link for what I was looking at.
http://www.jegs.com/p/Eagle/763943/10002/-1/10759

Any help would be appreciated. Thanks

 

Just the basics...all small blocks after '86 were 1 piece rear main seal.

They were balanced on the front and used a weighted flywheel on the rear (or flexplate).

 

Double post!

 

Ok cool so should I go for the Externally Balanced, 1pc Rear Main Seal or the Factory Style (Internal Front, External Rear), 1pc Rear Main Seal?

 

Factory Style (Internal Front, External Rear), 1pc Rear Main Seal.

 

Thanks Don

 

Why not go internal balanced? I feel you have better choices of flexplates and flywheels. I have never had a good extenal balanced flexplate- I have cracked evey one I ever owned.

 

Good point, but usually more expensive.