m30

[nauvoo]

I've always been interseted in a e30 m30 swap, mostly because of the b6 3.5 alpina. Lately, though i've been confused as to how much horsepower will really be gained. Different sites post different results. I am looking for between 275 and 300hp without forcing. If I get the motor from a 1991 535i and get lucky enought to also get a manual transmission, what gains would I acheive without building up the motor?

[bmwe28boy]

The m30b35 motor in stock trim will deliver apprx. 205hp/225tq. With some engine modifications, i.e. lots of head work and high compression pistons, you might could see 250hp. You have to remember that you are dealing with a single overhead cam motor here. However, this motor does take very well to FI. You can see numbers like 350 rwhp and over 400 lb.ft. torque with 1-1.5 bar of boost. You will never get the numbers you are looking for in an m30 that is NA unless you spend upwards of $10k on a build and it is just not worth it when you can turbo for $5-6k.

[nauvoo]

I might have to look into maybe a m50 swap for the horsepower I'm looking for (n/a)? I'm really not feeling the FI alternative. I guess I could be happy with 250hp, I don't race, just love to drive......

[lithium726]

You're not going to get 300HP out of an M50 NA either.

You would be looking at an S54 or an S52 with a LOT of modification.

[nauvoo]

I've decided to purchase the wrecked 535. I've decided that 300hp is not attainable, so I'll shoot for 250, if I don't get that, so be it. It's a small car and I still like the style and it's fun to drive. thanx for the info. I'll post all pics of my project as soon as I get underway this spring.

[xatlas0]

I've decided to purchase the wrecked 535. I've decided that 300hp is not attainable, so I'll shoot for 250, if I don't get that, so be it. It's a small car and I still like the style and it's fun to drive. thanx for the info. I'll post all pics of my project as soon as I get underway this spring.

250 is pretty optimistic. To get that, you'll need:
Custom pistons (~10:1 CR)
A 272 or 284 cam
A 3.9L displacement
Custom tune
Headers

That would get you to 250hp. You would have considerably more torque, though, probably like 275.

I did see a set of E30M30 motor mounts up on ebay a few days ago. They may still be there, and they are crucial to your project. Here is an excellent website for your swap:
http://www.e30.de/335i/00.htm

[maffoo]

m30's ruuuuuuuule
so much torque

[nauvoo]

I saw the motor mounts on ebay, they were right hand drive from Australia. I've spoke to a couple of people about the motor mounts and there are a few different options, I think getting them from Alpina is the right way to go. I'ts more costly but probably the safest. The question I have is why would I have to increase the displacement to 3.9? I'm planning to have a lot of headwork, forged pistons, new cam etc...I hadn't planned to increase the bore I guess I just didn't think there was much room for that.
Also, the other sites I had looked at, had the B6 3.5s making around 250hp(conservative) and hadn't mentioned increasing the displacement, hence 3.5s.
Please point me to the honest specs, I realize people like to talk up their cars and might exaggerate the numbers a bit. thanx again

[lithium726]

Just out of curiosity... can one throw a non-vanos M50 DOHC head on an M30?

3.9l M50 would ROCK.

[xatlas0]

I saw the motor mounts on ebay, they were right hand drive from Australia. I've spoke to a couple of people about the motor mounts and there are a few different options, I think getting them from Alpina is the right way to go. I'ts more costly but probably the safest. The question I have is why would I have to increase the displacement to 3.9? I'm planning to have a lot of headwork, forged pistons, new cam etc...I hadn't planned to increase the bore I guess I just didn't think there was much room for that.
Also, the other sites I had looked at, had the B6 3.5s making around 250hp(conservative) and hadn't mentioned increasing the displacement, hence 3.5s.
Please point me to the honest specs, I realize people like to talk up their cars and might exaggerate the numbers a bit. thanx again

The highest output NA M30 I have ever seen is Paul Cain's, which is in his 3.8CSi coupe. He did:
Port & Polish
3 - angle valve job
Larger valves
Started with a 12:1 CR, but that pinged, so he dropped it to (I think) 11.2:1
A 292 cam
~3.8L displacement bump. He used a M90 as a base block, which meant it had the same bore as a S38, then he snagged the S38B38 crank and used it.
If I recall right, he is also running Tec3 for engine management.
Headers
Intake
Port-Matched intake and exhaust

After all that (~20-30k$) he only got 280rwhp. The 250 you are talking about was likely crank hp, rather than wheel hp.


Just out of curiosity... can one throw a non-vanos M50 DOHC head on an M30?

3.9l M50 would ROCK.

No. The only head that would have logically fit (the S38 head) doesn't. The M50 has a different length than the M30. The highest displacement M50 derivative I have heard of is 3.4L, using a BMW Motorsports crank.

[henno]

You should be able to attain reasonable figures without have to increase the engine displacement in the beginnig. Start off with a 3.5 is motor. I suggest doing the changes in steps. First starting off with external bolt on items like:

-long tube racing headers and exhaust
-bigger camshaft
-Air intake
-Computer chip
-lighten flywheel/but not too much
-increase rear end ratio/to get motor in its power & torque curb faster

See how that works out. Then if you are itching for more power, which is usually what happens, you may need to change some internal engine components.

There is available horsepower by removing some weight. Example:
-Fiberglass,carbon fiber Hood/Fenders/trunklid
-Racing seats
-lightweight battery
-Remove a/c system,heater system
-lighter wheels

Try that!