324td

[erehemantresni]

Has anyone ever modded this engine? Is it worth while?

[Sean]

There's a ton of eta owners that would kill for that crankshaft.

That's all I really know about the engine though. Sorry I can't be more help. :?

[Stu]

The only worthwhile part on the M21 was the crankshaft, because of the 81mm stroke and because it is forged. It is now obsolete since we have up to 89.6mm forged cranks available that fit M20's.

[E30godz]

is there another 81mm crank that is forged that fits M20's, and is somehow better? if not, then it isn't obsolete.

people may want an 81mm stroke over the 89+ stroke for whatever reason

[decay]

what about the exhaust manifold? same flanges as an i head?

[RedBaron86325]

what about the exhaust manifold? same flanges as an i head?

NO, top mounting holes will fit, new bottom holes need to be drilled to fit the studs. Ports 3 and 4 match, 2 and 5 are 2mm off, and ports 1 and 6 are 5mm off. It will work with modification, but a custom manifold will flow much better.

[skat 325is]

IMO the td manifold is'nt worth the hassle, just make a custom one.

[decay]

noted. thanks.

[Stu]

is there another 81mm crank that is forged that fits M20's, and is somehow better? if not, then it isn't obsolete.

people may want an 81mm stroke over the 89+ stroke for whatever reason

Why use an 81mm stroke when you can use 84mm, 85.8mm, or 89.6mm :?:

The cars with 81mm stroke don't pull near as hard as those with 85+.

[diegom6]

The only worthwhile part on the M21 was the crankshaft, because of the 81mm stroke and because it is forged. It is now obsolete since we have up to 89.6mm forged cranks available that fit M20's.

like what cranks Stu? The m50 US M3?

[Stu]

The only worthwhile part on the M21 was the crankshaft, because of the 81mm stroke and because it is forged. It is now obsolete since we have up to 89.6mm forged cranks available that fit M20's.

like what cranks Stu? The m50 US M3?

'95 M3 = 85.8mm
'96-'99 M3 = 89.66mm
'96-'99 328 = 84mm

all forged

[E30godz]

super steamy high revs dawg.

[Stu]

super steamy high revs dawg.

'

With 2-valve curtain area and a timing-belt----nope.

You can build street M20's in stroker form, whether it's a 2.7, 2.8 or 3.0+, and it will have the midrange, with a cam and tuning it will make some top end, but let's leave the serious revver's to the 24v's.

I've driven 3.0 M20's and 2.8's. The 3.0's come on quite a bit earlier, but both run out of steam.

[matt325is]

10 bucks says my 81mm stroke pulls harder than the 89mm stroke.

matt

[Rob]

that's cause you cheat matt