Where to get a good 331 short or long block

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i'm going 331 so i have some insight into this topic ...

if you're running boost, you probably want a forged crank along with forged rods and pistons.

if i had a garage, i'd build mine myself. you can get a prepped block and a kit from summit. the assembly actually looks pretty straightforward, if you just take your time and double check everything as you go.

you can also get prepped 4.03 bored blocks on ebay for about $750 shipped.

but i don't have a garage, so i'll be getting my short block from m&r engines. it is an extremely budget minded short block; it has a nodular crank, not forged. $1550 shipped

paul riva and others recommend rnh performance

get ready for people to ask why 331 and not 347.
 
Isn't a 331 a little more reliable than a 347? I dont know much about 347. I heard the piston pin sits to close to the oil control ring? but that was a long time ago that I heard that. If I was to do a 347 I would keep it N/A. How many miles could I get out of each? 331 with boost or a 347 N/A both with good tunes.
 
rustang94 said:
Isn't a 331 a little more reliable than a 347?

No, not at all. Both will be equally reliable depending on the build and machine work. As for mileage, NO ONE can tell you. Could last a 1/2 mile, could last 300k, it depends :)
 
IMHO if your going to run boost and a stroker...get a better block and get a better block before a forged crank. I am not saying dont get a forged crank BTW.

If/when I do another motor for a mustang (prob. not in this car...maybe a fox notch). I hope to do a turbo and 331-347 or that 35x overbore (.125??? overbore deal thingie). I would go at least dart sportsman and forged crank rods and pistons. I have heard good things about RNH so he would be on that list as well as a very good local builder who has built MANY MANY tough combos around here.

I just dont like the idea of a stroker in a stock block or good boost (500rwhp able) on a stock block, much less both.