Zokal

What is the difference between a 2-bolt main and a 4-bolt main? In general, do most people prefer 4-bolt. Also, did any of the Formula TPI 350 come with 4-bolt?

ME Leigh

No 3rd gen L98 350's came with 4bolts, they are all 2-bolts. The only L98 350's that had 4-bolt were the Corvettes. The number of bolts refers to the number of main cap bolt there are. 4-bolts are generally thought to be stronger on all SBC's except the 400. But for anything driven on the street it doesn't really matter and number of bolt will be strong enough.

AJ_92RS

A 4 bolt block costs nearly twice as much to buy main bolts for, as opposed to a 2 bolt block.

DoBeR

iTrader: (1)

Alot of people will argue that 4 bolts arent really that much stronger than 2 bolts. Alot of people also run the crap out of their 2 bolts and rev them hard and dont have trouble.

Personally I think the best bet is to get a 2 bolt block and have it machined to accept 4 bolt caps where the two outer bolts go into the block on an angle. These are alot stronger than the standard straight 4 bolt block.

cormyr

i agree that the 2-bolt converted to a 4-bolt splayed setup is ideal, but i disagree that a 2-bolt will hold up to anything on the street. how many times have you heard of someone grenading their block from pushing it too hard. 2-bolts just wont rev as high or hold up if you're pushing serious power.

Apeiron

Grenading the block? Almost never on any kind of streetable build.