View Full Version : 4 bolt main

12-21-2012, 07:53 PM
Whats a 4 bolt main?
Ive got a guy trying to sell me a 72 GMC ad he keeps mentioning "4 bolt main"

12-21-2012, 07:56 PM
the crank main caps are held down with 4 bolts as upposed to 2 (can handle more hp)

12-21-2012, 08:05 PM
Unless ur pushing 500HP it won't matter
Yea the crank is held down with a 2 bolt main on the front then 3 4 bolt ones for the rest

Punk in Drublic
12-21-2012, 08:32 PM
some guys even argue against the four bolt main as it leaves less meat in the block between the bolts :dontknow: ive never seen either fail unless your pushing some real power.

12-21-2012, 08:40 PM
Got ya thanks.
I thought it was something like that .............but its no big deal.
I should offer him less because its got a 4 bolt main.
See how he likes that/