Quick Help! Any issues with 6M Crank?

benk777

New Member
Jun 18, 2008
161
1
0
Waukesha, WI
I'm having legendofaces.com rebuild an engine for me, and the 89 core that he has access to has a 6M crank in it. Are there any issues with this? Should I hold off, or is this not a big deal?

Thanks.

Ben
 

jdub

Official SM Expert: Motor Oil, Lubricants & Fil
SM Expert
Feb 10, 2006
10,730
1
38
Valley of the Sun
The 7M crank is smoother due to it's full counter weight design, but it's heavier.

The 6M crank is lighter and can rev a bit higher.

This is why you see the lower redline RPM on the '90+ cars ;)

Personally, I went for the best of both...a 7M crank lightened, knife edged, and zero balanced.
(before you ask...it cost a lot)