Best internals for an M20 turbo

[88driftIS]

This is all good news. I just bought a t70 turbo, mls gasket, and new studs today. Now I just need to decide what to do with the eta head. Trash it for an is, or swap internals.

[NOTORIOUS VR]

just an update. Did a clean up tune on my buddys car. 400.49rwhp at 21psi on 94 pump.

No need to waste money on internals if everything is good on your motor and have a good tune.

[itsbrokeagain]

sounds like the same to me. I had a feeling 8.8 compression I could boost the crap out of it. So what..I pull the head off, do a new gasket and studs, and call it a day. turbo adaptor, swain coat the stock headers and port them a bit, and throw an HX35 on there. Done.

My shop is a distributor for Haltech on the east coast, so I have my engine management covered already.


Im sure the rods are stout..I saw them in various threads, and they are pretty stout. No cam or anything in my engine..stock redline with lots of boost.

[biker7j]

i'm turboing next summer, and with piece of mind knowing that these stock motors can take a bullet or two. all i'm gonna do is head studs and the thick head gasket. thats it. and a nice tune.

[Fuel4blood]

What a relief to hear these motors are so strong. I just bought a 89 with a 119,000 miles and was planning on turboing it. I was thinking 119K is to high for a turbo. It's good to hear these motors can handle it no problem.

[NOTORIOUS VR]

There really is no need to do ANYTHING to an M20 if you're planning on making around the 400WHP mark.

The 8.8CR is perfect for boost... 20-21 psi is not an issue at all for a stock M20.

My friends E30 runs 20psi daily that I did the stand alone on and tuned. It's a stock M20 down to the stock paper headgasket. The only thing the motor has is Raceware head studs. The motor had approx 270,000km on it when it was boosted. Now is probably very close to 290,000 if not past that.

The car get's beaten on many times a day and still hasn't missed a beat. The car was dyno tuned on a very hot & humid day @ 374RWHP @ 18psi on 91 pump. The car makes 400RWHP easily on a cooler day @ ~20psi.

I think a lot of people underestimate how strong these motors are when accommodated with a good tune.

[Erick]

I agree, but not at 12psi. I've seen a handful of stock bottom end (hell, stock period) M20s on boost and they never failed. I don't think there's any need for concern until you start going over 15psi.

Any catastrophic failures (meaning beyond a headgasket) below 15psi that I would go ahead to say that the most probable cause is either a poor tune or some part of the system was bad (cooling issues, overheating, etc etc)

- Erick

[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."

[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.

[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]

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.

[lennon]

100 miles a day !

[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.

[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...

[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?