Best internals for an M20 turbo

[akorcovelos]

Hey all, looks like I'm in for a rebuild on my M20b25, which fits well into my plans for a turbo. If I'm rebuilding the whole motor, I want to do it right. What do you all recommend for internals? I want to be able to run 12psi max, and plan on running MS. It should also be known that I drive this car 100+ miles per day, so I would like this motor to be pretty bullet proof, and I'm pretty new to E30s, so tell me whats out there to do this thing right!
Thanks in advance!

[AlarmedBread]

The best advice I can give you is to save your money until you can afford to have two cars, one for dd, one for fun.

FWIW, you should be able to safely run that on a stock engine if your tuning is good.

Same normal things you would do to any engine apply, forged pistons, stiffer springs to keep from breaking a rocker when you bump off the rev limiter and of course a good port/polish of the head.

[Primo]

yea, for 12 psi the stock internals should hold up granted you engine etc is in a good state of tune. a completely rebuilt engine, "bullet proof" would be a grip, probably in the realm of 6-10 grand i mean this is an ideal case where you'd be balanceing everything, forged this, lightened that....not saying this couldn't be done for cheaper, but i'm just saying be realistic with your goals for what you want to achieve and you'll be very happy with the result

-Primo

[carnerd]

yea, for 12 psi the stock internals should hold up granted you engine etc is in a good state of tune. a completely rebuilt engine, "bullet proof" would be a grip, probably in the realm of 6-10 grand i mean this is an ideal case where you'd be balanceing everything, forged this, lightened that....not saying this couldn't be done for cheaper, but i'm just saying be realistic with your goals for what you want to achieve and you'll be very happy with the result

I have gotten prices on a NEW, not rebuilt m20b25 for 3500$ Other then the lightening, its not that bad of a price.

[Erick]

Do an OEM rebuild with a Cometic HG and ARP studs. Spend the rest on tuning tools. 12psi all day with no worries.

[iNetForce]

Do an OEM rebuild with a Cometic HG and ARP studs. Spend the rest on tuning tools. 12psi all day with no worries.

I agree! Both the head gasket and the ARP studs are a most. Otherwise you will be blowing head gaskets left and right.

If you have a healthy engine do not go for the OEM rebuild, keep it at 10 psi and get yourself the head gasket and the arp studs, again, these are a must.

[mrsleeve]

X3 on the stock rebuild. It will be fine on 12 psi. Be forewarned ARP dose not sell head studs for the M20. Look into raceware studs they are just as good and you dont have to special order. Now before someone say "But VAC motorsports sells them" Those are not for the m20 they are for a different app an cut off to the proper length for use on the M20, they do work well, I just like raceware stuff my self.

http://www.raceware-fasteners.com/

[vlad]

I agree! Both the head gasket and the ARP studs are a most.

where can I get high compression quality head gasket and APR studs?

[PaulEZ]

where can I get high compression quality head gasket and APR studs?

Im not sure what you mean by "high compression quality head gasket" but if you're referring to an larger MLS gasket to lower compression (good for boost) you can source one from vacmotorsports - ARP studs can also be found there...

[Aptyp]

I know VAC doesn't advertise this, but ARP head studs are a bad idea. Call them and ask about all the cracked blocks around the studs. After that call Korman, and pretty much every tuner.

So yeah, had gasket is a must, and with copper gasket you can even use the gasket sealer (like most dragsters), but using new OE BMW torx bolts is the best option. Blown head gasket because of failed bolts is an unheard of.Even a NA engine, blown head gasket on an M20 is a rarity.

Have fun, want to see your build.

[lennon]

100 miles a day !

[NOTORIOUS VR]

don't even bother to rebuild u'r motor for 12psi.... get a fresh headgasket, and some ARP/Raceware head studs and you're good to go.

[Erick]

I know VAC doesn't advertise this, but ARP head studs are a bad idea. Call them and ask about all the cracked blocks around the studs. After that call Korman, and pretty much every tuner.

So yeah, had gasket is a must, and with copper gasket you can even use the gasket sealer (like most dragsters), but using new OE BMW torx bolts is the best option. Blown head gasket because of failed bolts is an unheard of.Even a NA engine, blown head gasket on an M20 is a rarity.

Have fun, want to see your build.

That's funny. You're the first one to say that. I will have to call VAC because they push ARP quite a lot, and I spoke to them briefly about it in the past, and they seemed more than happy with their product.

All others that I have spoken to outside the BMW community also share a positive view of ARP.

[NOTORIOUS VR]

If you crack a block using head studs it's no ones fault except u'r own (that or u need a new torque wrench LOL)... and clearly you should be letting someone else build your engine for you.

[blueapplesoda]

Do an OEM rebuild with a Cometic HG and ARP studs. Spend the rest on tuning tools. 12psi all day with no worries.

from my experience, you should get forged pistons as well, just because they are more forgiving to engine issues than stock pistons. Stock pistons Get some oversize ones just enough to allow you to bore and hone the block to cut cylinder taper out (will help with future blowby issues causing oil leaks from every seal on your engine). Throw in an MLS hg, head studs, and you are set for reliable power. The rest like bearings and gaskets, OE will suffice.

Ive pulled my head one too many times fixing stupid little problems I could have prevented by spending the extra dollar on the RIGHT stuff the first time (ie., not metric blues ect...). Get you tuning done right too, especially if you stay the stock piston route.

like they say: "Cheap, Reliable, Fast. Pick Two."