M10 boost threshold

[Deadskittles]

Hmm... Ive been brooding over my next build and a tantalizing idea would be an m10 with some serious boost. I guess a question of mine would be what is the max a built m10 could handle? 30-40 pounds?

[travish325]

Who knows. There's a lot of variables.

[Todd Black 88]

Well, BMW used the M10 block in formula 1 in the early 80's, to produce between 1300-1500 hp in qualifying trim. They ran 50-60psi of boost. They didn't last long at that level, but I would think 25-30psi would be doable with proper assembly and tuning.

[Deadskittles]

I believe in the qualifying trim it was closer to 80 pounds. Sources suggest 5.5 bar (multiplied by 14.69 psi) = ~80# of boost. Im just curious what people have maxed the blocks at. With H beams and forged pistons and a 2002 crank im curious if 40# of boost is achievable.

[HaloArchive]

The M12/M13 was capped at 1500cc, so much smaller than the m10. Which allowed for that amount of boost before block cracking. IMHO, a 1800cc M10b18 built up could probably handle 800WHP with a large turbo and ALS in place. It would not be very street friendly though without ALS.

[Deadskittles]

Interesting. Could there being a built valvetrain help? (high redline 9000-10000?)

Also, ive heard ALS can decrease the life of turbos, is this true? and how dramatically?

[LJ851]

[E30_Pare]

Good&Tight was running somewhere around 30psi.

If i remember correctly was pushing almost 400hp. Not sure if with nitrous though.

[Jaxx_]

Good&Tight was running somewhere around 30psi.

If i remember correctly was pushing almost 400hp. Not sure if with nitrous though.

367(?) whp on the dyno before it blew up.

There are a lot of variables with turbo tuning. Usually a full valvetrain is not something that "goes" when it comes to turbo motor failure. Things to worry about most are bottom end related. head studs, cooked pistons, bent rods, or even cracked sleeves. Don't get me wrong, valve train is important too, but you'll get more bang for your buck throwing in some forged rods and pistons than getting rocker arms that are designed to rev to the moon.

[TobyB]

It can hold as much as you can throw at it- dollars, that is.

2 liter forged fully- counterweighted crank, hemi'ed head, custom pistons, long rods
an earlier thicker 2l block from a 2002, that setup can take a lot of combustion pressure.

So you could then run a significant amount of forced induction.

If you ran a conservative cam and low static compression, yeah, sure, 2 bar.

You might make more POWER, though, with less boost and a more aggressive
compression and cam.

It's all just money. And some time.

t

[E30_Pare]

Would it be better to keep stock bore and add more boost? Than to sacrifice integrity going with 90-92mm bore?

[Deadskittles]

It probably depends on where the weakest point in the motor is. If you had a forged crank,rods,and pistons plus ARP, and MLS, i would assume the next weakest thing would be the bore? In other words if you are not running all that forged good stuff you wont be needing to worry about the bore because that probably wouldn't give out first. However for max boost with all the upgrades that would be the main concern, i.e. keeping stock bore would be the safest. Thats just my thoughts.