another question
#2
Yes, you can do both at the same time. Boring is making the holes larger in diameter (requires larger pistons) but it typically doesn't net you a whole lot other than nice new cylinder walls. You will here boring referred to as .030 over, .060 over, .090 over.. A 302, bored out .030 over becomes a 306. The thing to also keep in mind that is the more you mill out of the cylinder walls, the thinner and weaker the walls become and there is less surface area on top to hold you r gaskets in place. Stroking on the other hand, is typically putting in a different crank that changes the distance the pistons travel within each cylinder and can net some huge displacement gains. There is ususally clearance issues that need to be addressed withing the block so that the larger crank has room to spin without meeting the block. One of the favorite "old school" stroker motors is a GM 350 block with a GM 400 crank, you retain the wall thickness of the 350 but you get 383 inches of displacement b/c the cylinders travel further down on the intake and combustion stroke and go further up on the exhaust and compression stroke (unless you change the heads (combustion chamber volume) you will end up with a higher compression also).
As far as what's better? As I mentioned earlier, boring nets you very little from a performance perspective other than nice new cylinder walls, thus factory fresh compression (with new rings and the correct oversized pistion).. you can play with the pistons and add a dome to bump up the compression when you do a bore and it will get you some more power (and require higher octane). If you have an old worn out motor, then a rebuild with an overbore is very nice. Stroking is more involved with the machining but gets some great torque added. There are some tried and true packages out there from a couple of merchants for both our 5.0 and our 4.6s... If you're doing the stroker motor, it only makes sense to get a little .030 over-bore to clean up the cylinder walls (and add a couple more cubes). There's obviously a ton of other aspects to consider and this is about as far as my knowledge can take me.. I did one 347 quite a few years ago and it was a no-brainer package (dropped the block off at the machine shop and got all the other parts in the mail to put it back together)
Hope it helps a little
As far as what's better? As I mentioned earlier, boring nets you very little from a performance perspective other than nice new cylinder walls, thus factory fresh compression (with new rings and the correct oversized pistion).. you can play with the pistons and add a dome to bump up the compression when you do a bore and it will get you some more power (and require higher octane). If you have an old worn out motor, then a rebuild with an overbore is very nice. Stroking is more involved with the machining but gets some great torque added. There are some tried and true packages out there from a couple of merchants for both our 5.0 and our 4.6s... If you're doing the stroker motor, it only makes sense to get a little .030 over-bore to clean up the cylinder walls (and add a couple more cubes). There's obviously a ton of other aspects to consider and this is about as far as my knowledge can take me.. I did one 347 quite a few years ago and it was a no-brainer package (dropped the block off at the machine shop and got all the other parts in the mail to put it back together)
Hope it helps a little
#3
Forget that, even more old school is to grind down the stock crank journals to SBC size and the difference there is the amount of stroke you gain. However, as mention, boring yields little since the size increase is very marginal. Plus, it should be done to what is needed by the machine shop to clean up the cylinder walls. If they say they only need .01" over, then that's what you do. Going to .03" or more off the bat means you'll be less likely to rebuild the block in the future. Some popular stroker options for Ford engines is throwing a 302 crank in a 289 to get 302, the usual 331/347/349 stroker packages, the old school way of throwing a 400 crank into a 351W/M (though it's harder w/ the W and is not worth it anymore w/ 393 and 408 packages), a 428 crank in a 390 or 427 (which yields 410 and 454 respectively), 460 crank in a 429 to get 460ci and a 514 crank in a 460, and lastly, a 302 stroker package for the 281 (4.6). Pick what you like.
#4
lol i know what boring and stroking is....just didnt know if doin both was a good idea.... as for stroking ide probably do the powroll and jsut get longer rods and maybe new heads. but thats just me. ive never been a bore person.
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