2010年10月4日 · After dozens of blocks (both 2 and 4 bolt) I can report a 2 bolt block with studded mains will hold as much power (with all else being equal) as a 4 bolt in a non supercharged application. I used to have a high performance engine shop and specializing in Chevys for street, oval track and drag applications.

2007年4月2日 · 4 bolt main factory blocks are good to about 650hp in a SBC. In big blocks, you can get away with a lot more because of the beefier bottom end. The factory rods are the weak point. a big block 4 bolt main will take 800hp reliably and a …

2003年8月30日 · A friend of mine gave me a 400 that was in an F-100 he bought. He'd heard all the horror stories of overheating and was afraid of it. I needed a motor for a 50 chevy sedan delivery I was putting together. It was a 4 bolt main engine and I'd heard the 2 bolt blocks were stronger but the damn thing was FREE!

2011年9月28日 · After a month of going back and forth it has come time to make the decision to splay cap the block or leave it a two bolt main (studed) here are the stats.... 383 stroker, forged eagle crank, forged scat 5.7 rods, probe -22 dish forged pistons, vortec iron heads (906 casting, all new springs and valves machined for up to .600 lift), comp cams ...

2011年11月17日 · The question as to what a 4 bolt block is has been answered. As to being better suffice to say that some of us prefer to start with a 2 bolt block and convert it to a 4 bolt block as part of the machining process. Unless you are building a balls to the walls performance engine a 2 bolt block will normally hold up just fine.

2018年10月10日 · Some people touting 4 bolt mains tend to forget or ignore what happened to 4 bolt main Chevies when first raced in NASCAR. It seems that the 4 bolt caps were thinner in the center and when dynamic forces came into play, the crankshaft would be forced down ever so slightly causing the a ring to pinch the journal and bang , lost motor.

2005年12月6日 · A 2 bolt block actually has thicker main webbing. If you have your mind set on a 4 bolt main block, find a 2 bolt block and order up a set of splayed caps. This will require align-boring the mains, though. The end product is much stronger than a factory 4 bolt block. If you're building a healthy street engine, there's nothing wrong with 2 bolt ...

2010年9月3日 · The engine is partially filled, cryo treated, and has 4 bolt splayed main caps on the center three mains. We had no issues up to about 550 horsepower. We noticed metal transfer on the front main cap at around 575 horsepower, and …

2008年12月31日 · The freeze plugs don't identify a 400 vs 350, if a 400 has only two freeze plugs on the side of the block it's a two bolt main, if there are three plugs on the 400, it's a four bolt main. The above identifiers are correct, the larger, relieved harmonic balancer, and the steam holes are giveaways.

2019年6月28日 · “It featured a 302 cu in (4.9 L) V-8, 3 in(76.2 mm) stroke crankshaft with 4 in (101.6 mm) bore, an aluminum intake manifold, and a 4 barrel vacuum secondary Holley carburetor of 780 cfm. The engine was designed specifically to race in the Trans Am series (which required engines smaller than 305 cu in (5.0 L)).