hightower2011

Damn that's lucky! Those are some great prices for machining!

frdnut

No four bolt mains on a windsor?

hightower2011

Yeah mine didn't have 4 bolts...

67mustang302

That's the way to do it then. When I went to school I had no projects of my own, so had to work on other people's engines. Just make sure you practice on some 4 cylinder engine or something before you do yours. Especially when it comes to grinding seats.

And 4 bolt mains are largely over rated. The bolts hold the cap in place, the only way a 2 bolt would fail because of having 2 bolts would be if the bolts themselves failed, or the bolts ripped out of the bolt hole. Theoretically 4 bolt mains are supposed to spread the load out over the main webbing to prevent the bolt holes from tearing or the web from failing, but every 2 bolt I've seen that's failed has pretty much ripped the entire main web right out of the block.....with the cap still neatly torqued in place, bearing clearance and all. 4 bolt mains wouldn't have saved that.

The aftermarket blocks that come with 4 bolt mains, splay the outer bolts and actually DO distribute loads better, but also have much better main web designs. But, they're also intended for highly abusive applications, high rpm, high power etc, some of the blocks rated for over 1,000hp. But factory blocks usually fail in the same places whether they're 2 or 4 bolt, and usually at around the same power/tune levels.

The GM LS engines are really nice, 6 bolt mains. 4 on the bottom(I think the outer 2 are slightly splayed iirc) and then 2 more bolts that cross bolt from the outside of the web into each side of the main. When was the last time you heard about an LS engine pulling a main off? =)

woody99

found out today that im gonna need to bore the cylinders so its a reason to get performance pistons and rebuild the whole engine. took the pan off and this is not a 4 bolt main engine but no biggy

frdnut

There is no such thing as a 4 bolt main windsor block.

mr_velocity

I know, just being a smart a$$. In his other thread where he asked for advice then just ignored everyone he said he was going with the 351w. One of the reasons he gave was a 4 bolt main. Like the rest of the thread he ignored that fact too.

PaulS

There are no FACTORY four bolt main 351W blocks......
There are four bolt main 351 Windsor blocks though.

frdnut

Ok gotcha...I wondered if I was missing something..

JMD

There are factory four bolt main SBCs, but as stated, no Windsors.

Just a "fun fact", but a lot of today's prevailing thought is that factory four bolt main SBCs are not as good for performance as many of the two bolt main blocks.

Also, the 351 Windsor's main bolts are bigger than the SBC.