3.9L M30 Stroker

[Robin-535im]

Metric Mechanic sells one for $8k-$9k.

I confess I stole the idea from Jeff N... but I bet I could build one myself for cheaper, maybe slap on a MM head with the 294 cam and the fancy-schmancy uber-flow technology surface roughness feature Jim talks about.

1) anyone have a used-up M30 short block they want to sell? How much?
2) anyone here ever do this before?
3) should I add an oil cooler?

The DME should do just fine with bigger injectors and a custom chip and/or piggyback ECU.

If anyone's ever done this or heard about it, please pontificate.

TIA

Robin

[bjl4776]

I have a shortblock from the 3.3L M30 from the e28 if that would work?

[Robin-535im]

AFAIK, the difference between early and late M30's was mainly in the head, but the displacement being different may mean that the bore was less. Shouldn't matter if I bore it out anyway. What do you want for it and where are you at? I'm not ready to pull the trigger quite yet but send me a PM and we'll get in touch off line.

- Robin

[AllanS]

Didn't PatP in FL do something like this on his turbo 535i? Not the Alpina one, his other 535i turbo :)

I think he had it out to 3.8l with a ported head on top.

[Paul in NZ]

what block does the 3.8m5 use????what are the dimensions of that motor vs the 535???

[Mr Project]

I also have an extra M30B32 block from an E28. I'm in Lincoln, NE, and the price would be VERY reasonable. E-mail me if you're interested. armenb1 AT juno.com

[cary]

Pass on the Metric Mechanic Stuff. Their theories are nice, but in actual practice don't work well. I have heard story after story about their motors not making close to the claimed output, having cranks break, etc. If you want more power follow tried and trued methods for modding the M30. I believe you can bore to 3.6 or 3.7 liters and DR. Shriek makes cams (keep it small with injection).

[bahnstormer]

turbo would be cheaper and more powerful anyway =]

[Robin-535im]

turbo would be cheaper and more powerful anyway =]

But for me it's not "BMW-enough". Adding a turbo goes too far from the way a BMW should be. When they put one in the 745, they used a different piston and stroke... just slapping on a turbo doesn't make me feel right.

Like I said, nothing wrong with them in general, and I don't mean to offend people with turbos because they probably make your car wicked fast. People may mod to their own tastes... but it violates my sense of the car spirit of natural induction.

[bahnstormer]

NA is def a very cool and respectable way to go...
but it takes a lotta cash and two brass ones....

power per dollar FI is gonna beat NA.....

however may i suggest korman....they have
a 250hp carburated setup for the m30 ....?

[Sean H]

If you were interested, I have an M30B35 with 126k on the clock. It has all the accessories (minus the A/C compressor) and the brain box (not sure how necessary these would be if you're planning on major mods, but I thought I'd let you know anyway).
PM me if you have any interest.

[535ise]

How much capacity increase can you get with a rebore and new(custom ??? )pistons ?

I thought the way to stroke the M30 was to use the 3.8ltr m5 crank and modify the chain sproket's ? I don't know what rods or pistons you would need to get the piston to head clearance right ?

If you bored and stroked it how big could you get the M30 capacity up to ? 3.9Ltr ? 4.0Ltr ?

[bjl4776]

I completely agree with you even though i went F1 on my 525i. I give complete respect for bmw for creating NA motors that companies such as Audi and MB have trouble matching with any kind of forced induction. But imagine what could be done to an NA motor with such high output when a forced induction system is added, properly of course.

[Tiger]

i remember Euro Cars magazine was talking about stroker BMW engine... They used M30 engine with diesel crank to stroke it which already makes it 3.8L... no boring required. I believe they used Shrick cams to match it

Let me get this straight... it was the eta engine block, diesel crank and the "I" head.

Good luck... don't ask to dig up that magazine... long gone...

[Robin-535im]

From what I understand, you can get to 3.7 with the same stroke but larger bore, or go all the way to 3.9 if you stroke it too. I think all the parts are available off the shelf. What I really need to do is track down Jim Rowe at MM or someone at Korman to get the real dirt on what is easy / cost effective to do.

Has anyone on this board actually done this to an M30 themselves?