Do you have a M20 hot rod or swapped Motor?

[Eurotrash727]

If you want to Turbo you m20 for track purposes use a Really efficient internal gated turbo. I know Sr's are known to make 300whp or a little more on a Disco potato "gt28r" with supporting mods.

[Raxe]

I like the big stroker M20 because it's period correct and sounds sweet at idle. That's a lot of questions in the OP, but lets just say I'm happy with my choice even if it's been a pain in the ass to keep running right lately. It probably costed more than an S5x swap but was easier to do IMO, and you don't have to fiddle with anything to retain all of your features. Fuel economy is as expected for a brand new engine - pretty decent. The only thing I'd do differently is find a better fuel management option.

[firemanory]

I like the big stroker M20 because it's period correct and sounds sweet at idle. That's a lot of questions in the OP, but lets just say I'm happy with my choice even if it's been a pain in the ass to keep running right lately. It probably costed more than an S5x swap but was easier to do IMO, and you don't have to fiddle with anything to retain all of your features. Fuel economy is as expected for a brand new engine - pretty decent. The only thing I'd do differently is find a better fuel management option.

Did you do the build of your motor yourself? Are you happy with the gains achieved, or do you find yourself wanting more?

[F34R]

My long term is 350 to the wheels on a built m20b27(seta)

So far what is done:

Schrick 288 cam/Schrick HiPerformance springs(rated to bursts of 11k)
IE HD rockers
MLS and ARP studs

Then boost like a madman with a clutch to put it to the ground.

[mikeedler]

I love my M20 because of its rawness. It sounds great with headers, may not be the fastest thing, but a good motor for the E30. after saying that, I def. am going to go euro S50 one of these days though.

[SpeicherBimmer]

My M30 with headers and full exhaust sounds like Zeus yelling at WOT...plus you get the cool Alpina wannabe feeling. M30s in E30s just seems right.

[evandael]

Ain't no replacement for displacement.

Except a turbo.


My own opinion ranks these options, from best to worst on a smiles/$ ratio: proper running stock M20, M30, S52, LSx, proper turbo M20, built M20.

[F34R]

Ain't no replacement for displacement.

Except a turbo.


My own opinion ranks these options, from best to worst on a smiles/$ ratio: proper running stock M20, M30, S52, LSx, proper turbo M20, built M20.

I agree, I would rather have a s52 over anything else swapped. But if it was a built m20 turbo I would go with that. Power is not everything, I think the m20 parts are cheaper to get/come by. Maintenance is easy and minimal, you really cannot go wrong with a boosted m20. Cheapest swap IMO would be the M30b35, gobs of trq and feels like a freight train from low to WOT. I loved my e24 just because of the straight line fun.

I already went the m50 route once on one of my first e30s. I am going back to the m20 for a happy revving force induced monster. low to mid 300s it more than I would ever need for SCCA/Weekend track days.

I know in the long run to reach s52 power with my m20 is going to cost more than s52 swap. BUT in the end I will have a rebuilt m20 with everything replaced and a cute snail :)

For NA swaps for best bang it is M30b35 with a single mass FW hands down. Cheaper than a S5x and sounds amazing. IMO I would never S50 swap, not really worth it for the price of a S52 now days.

S54 is the perfect swap if you have the money, that engine is insane in the e46 M3. I have never gotten the honor to ride in a e30 with that...but I bet it is scary fast.

[evandael]

^ yeah, I can't deny how fun it would be to have a nice turbo M20. But doing it right is not cheap!

[george graves]

Cheapest swap IMO would be the M30b35, gobs of trq and feels like a freight train from low to WOT. I loved my e24 just because of the straight line fun.

If you like an m30 in an e24/e28 - you'd love it in an e30. An e28m30 feels like it's twice as heavy - the m30 really struggles to move all that mass. In an e30 the m30 behaves as if it's pushing a go-kart.

I don't mean to knock s5x swaps - It's a great motor. But in some ways it doesn't feel right in an e30 - almost too "smooth". But then again - it's a heck of a motor.

With that said. I know if I ever need a to do some head work on my m30 it's not going to cost me much. I pucker-up at the cost of a proper 24 valve rebuild.

And m50...pfff....not worth the effort IMHO. Unless your m20 needs rebuilding/replacing. Then pick one up for cheap. Cost will be about the same.

Also - since I'm on a rant - turbos just don't do it for me. I don't like the "SUSPRISE!!! YOUR ON BOOST" feeling in a corner.

Back to M30's - you won't find one person that has owned or driven a e30m30 that doesn't like all that pure, unadulterated, grunt that a m30 gives you.

An S5x is like the girl you want to marry - an m30 is the girl you don't bring home to mom.

[VinniE30]

An S5x is like the girl you want to marry - an m30 is the girl you don't bring home to mom.

sigged.:)

[mikeedler]

Also - since I'm on a rant - turbos just don't do it for me. I don't like the "SUSPRISE!!! YOUR ON BOOST" feeling in a corner.

this is the truth and exactly why I pulled the turbo motor back out of my E30 and just built up an M20!!!!!!!!! It was imposible to have fun in the twisties!!!!

[slammin.e28]

M30 > M20 all day, erryday.

[evandael]

so OP, unless you want an S52 (which you should keep OBD2), a proper turbo M20 (if you like turbo powerbands), or an LSx (if you have the dineros), y'all best swap in an M30B35.

[nando]

I have an ix, so an M20 makes a lot more sense. I'm done with M20s for now, and am working on something else - a swap in an ix, done right, will cost way more than a built M20. It really wouldn't make sense to do an M5x or even S5x swap in an ix, the power gains over a built M20 are just too small for the effort (I have about 210-220bhp with the M20).

also, comparing a $500 junkyard M50, to a brand new, custom built M20 with go-fast parts is stupid. If you built the M50 the same way it would cost far more.

M20s:
-simple to build
-cheap to build (relatively)
-easy to tune
-light
-sound better
-rev higher

M30s are cool too, just not my cup of tea.

huh? I'm not trying to convince anyone to do engine swaps at all, I like M20s. But if you want a high reving N/A motor than I think what you want is an engine swap, not an M20. And for starters, stroker and high reving don't go well together. If you want high reving then increase bore, not stroke.

this is absolute nonsense. All of the high reving M motors have a much longer stroke than a stock M20 or M50. the S54 has a 91mm stroke and revs to the moon. a properly built M20 with good headwork will do 7500+ no problem. an S5x reving that high will probably collapse a hydraulic lifter and be left permanently ticking. :p

M5x and S5x aren't exactly high reving engines. Not unless you throw a ton of dough at them. A set of schricks cost what, $2k? then you have 24 valve springs to replace, and you probably don't want to keep the hydralic lifters, so you'll need 24 aftermarket lifters, etc. etc. People have this illusion that you can build a 24v motor cheap, it's 100% BS. It's only cheap if it's a bone stock junkyard pull. building a 24v head probably costs 4x as much, and there's 2x as many parts.