M50b25 nv

[Slow318i]

Im rebuilding m50b25nv for boost purposes and im looking to make 500-600 to the wheels. Will a cutring and e85 be ok to do so? Or should i look into forged internals at this point? Also can i use m52 forged rods in m50nv? I know both are 135mm.

[someguy2800]

You should be able to make 500-600 whp on a M50B25nv with just a cutring head gasket, head studs, and E85. The M50 rods are forged and are much much stronger than M52 rods so definitely don't do that. We've made 800+ whp on stock non vanos rods with an M52B28 crank and M52B28 pistons.

[Slow318i]

You should be able to make 500-600 whp on a M50B25nv with just a cutring head gasket, head studs, and E85. The M50 rods are forged and are much much stronger than M52 rods so definitely don't do that. We've made 800+ whp on stock non vanos rods with an M52B28 crank and M52B28 pistons.

Ok. Well then ill just have everything cleaned and replace all the seals. Probably new piston rings and rod bearings aswell.

[someguy2800]

Don't let the magic out unless you see some actual wear of some kind. The non vanos motors came with moly faced rings from the factory and about 50% of the time the rod bearings still look new. Would be a good idea to gap the stock rings.

[Slow318i]

Don't let the magic out unless you see some actual wear of some kind. The non vanos motors came with moly faced rings from the factory and about 50% of the time the rod bearings still look new. Would be a good idea to gap the stock rings.

Machine shop quoted me 200$ to clean my block and head. So the rebuild begins...I have a few questions, what do i gap my rings to, where would i find a good cutring H/G and are arp 2000 going to be strong enough? Ive heard of 2000s stretching so i was thinking 625s...

[someguy2800]

.019 on the top ring and .021" on the 2nd ring should be fine. CES, MaxPSI, Summit Racing, and Boost Monkey all sell cutring gaskets. All the brands are the same, just repackaged. ARP 2000 will be fine.

[Slow318i]

Would m50 stroker be a better idea for my situation? M52 pistons and crank?

[someguy2800]

If you want a really bullet proof setup for cheap the non vanos M50 blocks typically have perfect cylinder walls, so If you get a set of either stock M52 pistons or a set of wiseco KE118M84 pistons and put them in the M50nv block with the M50nv connecting rods, and M52B28 crank, you will have a very stout 2.8L ready for E85. I have ran 9.4 @ 149 at brainerd with that engine combination.