w8less

some friends and I were talking at work about how we thought this is possible. Converting a 2 bolt to a 4 bolt block. All i have ever heard is that it weakens the block. Is this true or merely fiction? IF it is true how so?If you think about it wouldn't in a sense gain strength from the 4 bolt mains or would it still have the same weakness that we all know the stock block has?

Also another point that was brought up was filling the block some. Doesn't this Strengthen the block also? Would/Could this be an alternative to get some added strength for just a weekend warrior? is there any real downsides besides the extra weight?

Please help solve some curiousty and to think this all got started from a friend with a chevy 2 bolt. He is worried about cracking his block with his 383 with solid roller cam and a supercharger coming up

nasty50

you technically can make your stock 302 a four bolt, but to my knowledge it won't do any good. the webbing is what goes on a stock block. just get a main girdle if your worried

w8less

why wont it do any good? and how would a girdle be better than that of a 4bolt conversion

redmustang83596

Most of the time the block will fail along the lifter valley, so you would be wasting your time and money. It would probably be stronger to get a main support girdle then to convert to a 4 bolt main, but then again, thats not where most block failures are.

ACE

The only thing a Main girdle is good for if your making lots of horsepower its to keep your parts from flying around and hitting your oilpan.

AdderMk2

converting a thin web block to 4 bolt mains will actually weaken the motors bottom end and will allow it to fail easier

Gary H

There's not enough metal in the web area to convert to 4-bolt mains anyway. SBC might be different, but there are enough 4-bolt 350 blocks around that it's probably cheaper to buy one then have one converted.

w8less

does filling the block help any? does anyone have personal experience with the girdles or is your info all e-say?

nasty50

filling the block??

AdderMk2

just dont do it