351W overbore sizes?

[Mercracer]

Shouldn't be too hard to find a roller 351 if later trucks/vans came with them. Not sure about this. I keep hearing 6000 rpm and 600 HP are the reliable limit for a stock 351W. Someone out there makes a kit to convert to the smaller main bearings of a 302 to get higher RPM. While I like the idea of a high-revving V8 I'm not liking the reduced longevity of the motor due to the high piston speeds, which is why I've abandoned the idea of a stroker. 400+ CI would be nice, though. I'm very tempted to find a low-mileage 302 H.O. longblock for the simplicity of it all. .....

700HP+ and 6500RPMs is no problem for any 351W block if your rotating assy is up to it. 3.85 stroked 351W at 6500RPMs isn't even a problem. 94+ roller blocks are pretty easy to find since these trucks are all over 10 years of age now. 1969 to early 70s blocks are stouter to some degree but I am betting that you are never going to stress a late roller block beyond what it is capable of. These theories of running heavy oils in street vehicles is what killed many of the 351C, 351M and 400 engines. 5W-30 is good for most climates nearly year around. In the very warm climates, you can step up the oil weight but few places need 10W-40.

[1987cp]

These theories of running heavy oils in street vehicles is what killed many of the 351C, 351M and 400 engines. 5W-30 is good for most climates nearly year around. In the very warm climates, you can step up the oil weight but few places need 10W-40.

Very interesting, as I've also been in the habit of running 10W-30 in the winter and 10W-40 in the summer, even though I've read articles extolling the benefits of superlight oils such as Mobil1's 0W-30. I assume this way of thinking has at least a little bit to do with what sort of clearances the motor has when you assemble the thing?

[Mercracer]

Very interesting, as I've also been in the habit of running 10W-30 in the winter and 10W-40 in the summer, even though I've read articles extolling the benefits of superlight oils such as Mobil1's 0W-30. I assume this way of thinking has at least a little bit to do with what sort of clearances the motor has when you assemble the thing?

Yes. Factory builds use tight clearances. Ford recommends 5W-20 Motorcraft year round which is a synthetic blend for its Mod motors and all other motors built the past bunch of years with the exception of the Zetec 2.0L and OHV 4.0L motors which it recommends the Motorcraft 5W-30 Synthetic blend be used year round.

[Mercracer]

the mexican block is marginally stronger than a regular block, a $900 sportsman block is basically the same as a early 70s block. the R-block, new BOSS block, dart and world blocks are good to 2000+ hp, but cost over $2000, and that does not include the cost of machining to make them useable since most are sold with rough machining

The Mexican block is good for another 100HP over any other factory 302 or 289 block. The $900 sportsman block is superior to even the Mexican block. The other early 70s blocks suck in comparison. It should be good for another 100HP+ over the Mexican block or 200HP+ over a late model roller block. If you look at Ford's conservative ratings, they reflect a rated 150HP advantage over a 5.0 roller block. Ford's ratings reflect circle track abuse which puts more strain than a street strip or even strip drag race application with a reasonable tune.