E30 with M30B35

[Lurker27]

A few things. Rebuilt from the bottom up, turbo M30b35 swapped e30 owner here.

1. The M30b35, healthy and with a chip, is a shade above 240bhp, with a monster torque midrange of over 260lb-ft. Because of the shape of the torque curve, they produce more area under the curve than most 24V swaps. S5x swaps are better, particularly when cammed + m50 manifold.

2. In terms of mechanical and electric difficulty, the M30 is probably harder than the m/s5x at this point. You need the right harness and the engine will always fit worse in the bay. You also need more big ticket parts. The M30 engines themselves are slightly cheaper than even m52s, but cost is largely a push at this point.

3. The weight difference is negligible. If you have the lightweight e34 b35 casting, you are losing weight compared to a 24v swap.

4. bashing the firewall is a GOOD THING. Moving the engine further back is a GOOD thing. If you buy mounts that don't require a bashing, you bought the wrong mounts.

5. Feel: The m30b35, with it's slightly-hot 276 cam and "Big typewriter" valves, is the I6 that wants to be a V8. That's how they drive. They're even a little lumpy at idle, but once you're into the glorious midrange powerband, it settles into the BMW I6 smoothness. It really is a glorious engine - if S38 maintenance costs weren't ridiculous I'd kill to own one.

The m52/s52, on the other hand, is buttery smooth and refined through and through.

The M30 is an M20 on steroids. The M50 is the M20 with a college education.

[MR 325]

Yes, the hardest thing about the swap is dropping the engine in! :)

On my buddy;s we used the stock driveshaft, swapped the small flange on to the trans. We used the stock wiring harness from the M20, it was awesome! Very simple swap.

[schtozo]

My m20 spins 6th and its even an autotragic :pimp: WTF??

Hahaha but seriously i got into the m30 e30 in the video i posted few posts back and it was really fast for being stock and itvreally spinned second gear easily, dont remember third though...

[E30SPDFRK]

I can't believe there's still people spouting off wrong information about m30 swaps. If you don't have first hand experience, don't say anything.

The m30 swap may have been harder then an m50 swap a few years ago, but with all the collective knowledge we have now a days it's way easier. You need engine mount arms and a driveshaft from an 87 325e, that's about it. No new booster, no wiring adaptors, no custom transmission brace, no specific oil pan, etc.




And I've asked this before, but what do you guys consider "spinning third gear"? Because I can tell you there is no way in hell an m30 swap can truly spin 3rd gear without forced induction or donught tires. My m60 swap doesn't even spin 3rd.

[Zacm829]

Do it. Transforms the car and the M30 takes boost much better than the M20. If you already have the drive-shaft figured out, your home free.

[LJ851]

I really miss my 3.7L M30 E30. It was a no A/C no PS car as well and a blast to drive. I posted a dyno graph over in the M30 section plus some descriptions of the driving experience.

[MR 325]

The M30B35 is a GREAT swap. A buddy did one and it was cool. Another great thing about the swap, it's different than the norm of 24v motors. I drove the car numerous times and I didn't feel like it had a "heavy front end" but it also has no A/C or P/S.

[BMC227]

You can spin 3rd in m10 car if you put 500 treadwear tires...that's not really a good way to measure anything lol.


Why bother upgrading motor if you can't put the power down....

wheel spin = waste.

Not necessarily, my old e28 which had a modified m30. It would let go 1st, 2nd and chirp thirds and that was with 9.5 inch wide 17 inch alpina wheels with 265/40/17 Bridgestone Potenza tyres and they're known for their grip/handling.

I wasn't using that question to determine how fast and how much power an e30 m30 has.

Was.

[matias88e30]

Look for "good n tight".. his turbo m30 its a beast!.

[Jean]

You can spin 3rd in m10 car if you put 500 treadwear tires...that's not really a good way to measure anything lol.


Why bother upgrading motor if you can't put the power down....

wheel spin = waste.

[mkcman17]

No need to get testicle. Just saying, you can reliably turbo an m20 on stock core internals with basic ems and destroy most swap cars.

[BMC227]

also why the hell would you spend 15-20k on tuning? wreck your car 5 times?

If you read my post clearly, what i meant was if you're going to build a turbo engine, there's no point in using standard internals and standard fuel/ignition management. If you're here to flame me, please get the fuck out.

Yet you'd bash in your firewall and shoehorn a larger displacement, SOHC i6 in there? Both swaps have their upsides and downsides that reasonable people can understand, however, you make no sense, and I don't believe you understand how cars work.

If you use the correct Alpina mounts, the firewall requires no modification. Oh lol thanks for that :)

The b35 needs no firewall modification.

That is true

[chadthestampede]

Yet you'd bash in your firewall and shoehorn a larger displacement, SOHC i6 in there? Both swaps have their upsides and downsides that reasonable people can understand, however, you make no sense, and I don't believe you understand how cars work.

The b35 needs no firewall modification.

[Roysneon]

M50/52/54 I will never do because you're ruining an e30, i'd rather buy an e36.
.

Yet you'd bash in your firewall and shoehorn a larger displacement, SOHC i6 in there? Both swaps have their upsides and downsides that reasonable people can understand, however, you make no sense, and I don't believe you understand how cars work.

[mkcman17]

when driving overly aggressive i can chirp third in my m20 3.73. i don't really think spinning gears is a good reference for speed.

also why the hell would you spend 15-20k on tuning? wreck your car 5 times?