engine and drivetrain M10 Vs. M20 - *flame Suit On*

[M3M3]

+1

been racing in cars with M20's for a dozen years. work great! race in cars with M50's too. M50 better because of power potential, but M20 is a no-brainer fit in a 2002. an M50 is not.

but m20 does have 50% more of those dang rocker things as Toby says....

Edited December 2, 2013 by mlytle

[peterschop]

 

The M50/52 S50/52 is roughly the same bottom end, but with a vastly improved head and flow characteristics.  So why not go that way?

 

 

 

Now there's an idea. Instead of selling my e39, I can pull the engine and stuff it in my 02.....  Not.

[Pierre]

The M/S/50/52 has no rocker thingies.  The cam sits on a lifter over the valve.

The M42/M42 is the same.  In fact, all dual cam 24V engines have that set up, the only difference being the lifters being hydraulic non-adjustable or solid like the earlier dual cams (S14, S38) which require a tedious valve adjustment using shims.

[TobyB]

 

 

M20 engines are raced all the time, and  successfully.

Ok, ya got me.  I even race one.  But I DID light a fire under ya butts!

 

BMW never did, though, and they even raced the M42 (as the BTCC S42. I would LOVE to have one of those!)

 

A common (one could almost say, usual) sight at a Pro3 race is someone changing a rocker arm.  They give up

with unpredictable frequency.  So I'll stand by my assessment of the M20 as a very dated, 2- valve engine.

 

And a very good fit into a 2002.

 

Better than, say, a rotary or an F20C out of a Honda S2000...

 

hee

 

(again)

 

t

[Poon]

At some point, you will lose the ability to hold traction.  And you might want to build brakes to suit  Find the balance at around 200hp, and be happy there. 

 

Oh, and for those of us who don't like BF.com, post your engine recipe/swap in a project blog..

I think the perfectly usable power number in the '02 chassis is around 220-250hp at the crank. With my stock M20 you only have traction issues if its WOT or you're not driving the car smoothly. I have a spare M20 long block that I would like to build into a 3.1L stroker which I think will get my '02 much closer to that "magic number" that makes the car scream like a banshee but still has usable power.

I do agree that the M5x engines have some better technical updates such as twin cam, hydraulic lifters, and intake vanos but the version of Motronic is marginally better than the Motronic1.3 found on late model M20s and those plastic intake manifolds would look just aweful and far too modern under the hood of the '02. At least the M20 has a pretty aluminum intake manifold.

Lastly, I still love the M10. It's just big big $$$$ to make them put out "good" power.

 

[TobyB]

I think an aluminum- block M88 would be perfect in almost every way.

 

Except length.

 

heh

 

t

[kid2002]

I'm thinking M20B27 with an 885 head. MS and a good tune.. Maybe turbo but I really want to keep it simple..

[TobyB]

If you want simple, run the stock ECU with a chip, maybe from Mark D'Sylva (sp?)  Free- flowing exhaust, and you'll have

enough poot to get started, at least.

 

t

[kid2002]

Yeah the chip is nice but already almost half the price of WhoDWho's plug and play MS setup for our cars.

That opens up a whole new world of possibilities. Not to mention simplicity. Factor in the reliability and it's a no brained.

[Kpeters]

I have an euro E21 with a 2.7, 4 barrell carb and "i" head and it's a BLAST to drive. Can only imagine how much more fun it will be on a car that weighs much less and feels like a go kart!

[kid2002]

Mounts should be in tomorrow.

When I got the 02 that needed an engine and I recently finished my M20 build it was really a no brainer.

When I first got into cars I always wanted a MK1 VW Rabbit with a VR6 engine in it.. I'm thinking a 76 02 with M20/G260 would be in that "realm" with much more class and heritage.

Got any pics of the E21? I'd love to see it!