[f22cameron]

Hey guys, I have a 2014 228i 6 speed manual right now and I'm considering swapping in a b58 and doing the doc race single turbo kit on it. I got my car for pretty cheap so I have extra money to do the swap. I was just wondering if anyone knows if the manual transmission from an n20 would line up with a b58, or if I would need to also swap in the transmission. I plan on doing an m2 style widebody kit and making it a full on track car. I would love to buy an m2 or m240i, but It would feel wrong to take an m2 or m240i and do the mods I wanna do to it. Please let me know, I'll keep you guys posted on the build. Cheers

[aerobod]

Originally Posted by f22cameron

I was just wondering if anyone knows if the manual transmission from an n20 would line up with a b58, or if I would need to also swap in the transmission.

Most of the mounting bolts will line up between the GS6-17BG in the 228i and GS6-45BZ transmission used with the B58, looks to be small modifications. The problem is the GS6-17BG transmission is only rated for 350Nm/258lbft of torque.

Also, I believe the clutch used with the GS6-17BG on the N20 has 22 splines, whereas the clutch used with the GS6-45BZ on the B58 has 26 splines, so using the higher capacity clutch from the B58 is not possible with the GS6-17BG, even though they are both 240mm in diameter and use the same clutch release mechanism.

The propshaft is also a different length (by about 80mm) and they use different differentials with both higher torque capacity and crown wheel size (188 vs 215mm) and significantly different ratios (3.91 vs 3.08).

The differential output shafts are also different, 30mm vs 35mm, i.e. about 23% weaker.

The rear carriers are the same, though.

Basically everything in the driveline between the engine and rear hub carriers is different, although it may be able to be made to work with minimal bell housing changes and putting the N20 clutch on the B58, but to be able to handle a tuned B58, the whole driveline probably needs to be swapped, too.

[InsideWorld]

Originally Posted by aerobod

Most of the mounting bolts will line up between the GS6-17BG in the 228i and GS6-45BZ transmission used with the B58, looks to be small modifications. The problem is the GS6-17BG transmission is only rated for 350Nm/258lbft of torque.

Also, I believe the clutch used with the GS6-17BG on the N20 has 22 splines, whereas the clutch used with the GS6-45BZ on the B58 has 26 splines, so using the higher capacity clutch from the B58 is not possible with the GS6-17BG, even though they are both 240mm in diameter and use the same clutch release mechanism.

The propshaft is also a different length (by about 80mm) and they use different differentials with both higher torque capacity and crown wheel size (188 vs 215mm) and significantly different ratios (3.91 vs 3.08).

The differential output shafts are also different, 30mm vs 35mm, i.e. about 23% weaker.

The rear carriers are the same, though.

Basically everything in the driveline between the engine and rear hub carriers is different, although it may be able to be made to work with minimal bell housing changes and putting the N20 clutch on the B58, but to be able to handle a tuned B58, the whole driveline probably needs to be swapped, too.

Makes sense I think he does plan on changing almost all of the Driveline and swaping the m2 diff, i just wasn't sure if they used the same Trans. I did see however that a few other people who have done similar swaps in touring cars have ended up going with some sort of Diesel Transmission from another F Chassis, i wonder what else would work because finding the B58 trans in manual seems very difficult to find in Canada at least also since its still quite new. very helpful info though i would be really interested to see if this build is possible/viable now that prices have changed!

[dradernh]

Originally Posted by f22cameron

I have a 2014 228i 6 speed manual right now and I'm considering swapping in a b58

Are you going with an aftermarket standalone ECU or will you use a BMW ECU?

[f22cameron]

Originally Posted by dradernh

Are you going with an aftermarket standalone ECU or will you use a BMW ECU?

I'm hoping to find someone selling a b58 with the ecu included, but seeing at that is unlikely I will most likely end up doing a standalone ecu.

[XutvJet]

Not to be negative here, but these aren't Miatas, RX-7s or the like where motor swaps are relatively easy. There's good reason why motor swaps are nearly zero in late model BMWs. The cars are simply too complex and BMW does weird things when it comes to varying wiring, components, etc. amongst makes, years, and even 1/2 years. They aren't like many other more standard automakers where parts bin sharing is common amongst many components of a car.

There are a number of other computers on the car other than the DME, but the DME talks to those computers. The level of "coding" on a BMW is bonkers too. You'll have to be an electronics and wiring genius to make all the systems work. It is NOT plug and play.

The Getrag 6MT in your 228 won't bolt up and it's not strong enough for even a stock B58. Same goes for the clutch assembly, flywheel, driveshaft, and rear differential.

With all that power, you'll need an LSD. That's $2.5-3K installed.

A used B58s are going for $6-10K right now.

Adding an M2 widebody will cost a hefty amount with body shop work and paint. Think $5K bare minimum.

I promise you that selling your 228 and buying a used 2016-2017 M2 6MT and adding a Pure Stage 2 will be much cheaper and reliable. Compared to the 228/235/240, the M2 comes with a superior suspension, front and rear subframes, chassis bushing, weight removal, and that amazing electronically controlled LSD. It also has the wide body you want.

[dradernh]

Originally Posted by XutvJet

Not to be negative here, but these aren't Miatas, RX-7s or the like where motor swaps are relatively easy. There's good reason why motor swaps are nearly zero in late model BMWs. The cars are simply too complex and BMW does weird things when it comes to varying wiring, components, etc. amongst makes, years, and even 1/2 years. They aren't like many other more standard automakers where parts bin sharing is common amongst many components of a car.

There are a number of other computers on the car other than the DME, but the DME talks to those computers. The level of "coding" on a BMW is bonkers too. You'll have to be an electronics and wiring genius to make all the systems work. It is NOT plug and play.

The Getrag 6MT in your 228 won't bolt up and it's not strong enough for even a stock B58. Same goes for the clutch assembly, flywheel, driveshaft, and rear differential.

With all that power, you'll need an LSD. That's $2.5-3K installed.

A used B58s are going for $6-10K right now.

Adding an M2 widebody will cost a hefty amount with body shop work and paint. Think $5K bare minimum.

I promise you that selling your 228 and buying a used 2016-2017 M2 6MT and adding a Pure Stage 2 will be much cheaper and reliable. Compared to the 228/235/240, the M2 comes with a superior suspension, front and rear subframes, chassis bushing, weight removal, and that amazing electronically controlled LSD. It also has the wide body you want.

I believe this is a useful reality check.

I think the best way to do this would be to take the car entirely apart and put back in it only those parts you absolutely need (i.e., not very many). The wiring harness would have to go, along with (hopefully) every computer already in the car.

A quality aftermarket ECU, a logger and a dash, and a custom wiring harness will each cost quite a bit. Doing all of the work yourself could conceivably keep the cost manageable. Having qualified shops doing the work would cost a good deal – where I've had work done I think it would be a $100K+ project.

To me, these cars aren't very good candidates for full-on track builds. Their weight alone continues to argue against it for me. They'll be expensive to run, too. But then so are P-cars. There are a fair number of those around, although most of the owners are in a bracket noticeably higher than that of most BMW-owning track day drivers.

As always, my 2¢.

[f22cameron]

Originally Posted by XutvJet

Not to be negative here, but these aren't Miatas, RX-7s or the like where motor swaps are relatively easy. There's good reason why motor swaps are nearly zero in late model BMWs. The cars are simply too complex and BMW does weird things when it comes to varying wiring, components, etc. amongst makes, years, and even 1/2 years. They aren't like many other more standard automakers where parts bin sharing is common amongst many components of a car.

There are a number of other computers on the car other than the DME, but the DME talks to those computers. The level of "coding" on a BMW is bonkers too. You'll have to be an electronics and wiring genius to make all the systems work. It is NOT plug and play.

The Getrag 6MT in your 228 won't bolt up and it's not strong enough for even a stock B58. Same goes for the clutch assembly, flywheel, driveshaft, and rear differential.

With all that power, you'll need an LSD. That's $2.5-3K installed.

A used B58s are going for $6-10K right now.

Adding an M2 widebody will cost a hefty amount with body shop work and paint. Think $5K bare minimum.

I promise you that selling your 228 and buying a used 2016-2017 M2 6MT and adding a Pure Stage 2 will be much cheaper and reliable. Compared to the 228/235/240, the M2 comes with a superior suspension, front and rear subframes, chassis bushing, weight removal, and that amazing electronically controlled LSD. It also has the wide body you want.

I know the swap would be far from easy and would put a big whole in my pocket, a lot of the things you brought up are things I would end up getting if I needed it or not, An lsd being one of those. My issue being when it comes to M cars I am a purist, I'd feel wrong doing anything to those cars. Where as my 228i, I won't feel bad doing stuff to it. The other issue being where I live 6mt m240s are zero to none.

A lot of the work for the swap, I can do myself and I plan of filming the whole thing to post on youtube for others to see. I just need a definitive answer on if the swap will work, If i swap in the full drivetrain of an m240i would i be actually able to do the swap? or will it not fit?

There are a lot of variables on how much it would cost, no definitive answer. I've seen people selling low km b58's for 3500 dollars. I've seen lsd's for 2000 dollars. Its very hard to narrow it down to a set cost until you actually do the swap.

I appreciate all the feed back from all of you <3

[dradernh]

Originally Posted by f22cameron

There are a lot of variables on how much it would cost, no definitive answer.

No, that is, exactly, wrong. I don't usually go there in that way, but it is. That is the way you dig yourself a gigantic financial hole. Ask me how I know.

You have a shop in your region that can give real world numbers as to what you're looking at, taking into account what you'll do yourself and what you may have to or choose to hire out. That shop is Raven Motorsports, and they know BMWs, backwards and forwards. You can reach them at: https://www.ravenperformance.com/. I have no affiliation with Raven Motorsports.

I recommend that you speak frankly with them, and/or with one or more other outfits in your region with similar knowledge, expertise, and records of producing positive results for clients turning their street cars into hard-core track cars. Believe me, it will not only save you money, it will save you a lot more besides.

The path you contemplate traveling is not an easy one, nor a simple one. That it's very expensive regardless of how you proceed goes without saying. There are a lot of ways to get it wrong, and no small number of people you'll meet whose interests are not aligned with helping you achieve your goals at costs you've imagined, hoped for, believed they'd be, or couldn't afford to pay more for. Bottom line (as with everything else in life): move and choose carefully. Alternatively, be prepared for surprises that may not be manageable.

[Maynard]

I'd second that recc to start with a first gen M car - hands down the best starting platform for track if you want to mod. If any of those are being treated 'wrong' it is the ones that don't get on a track. Do an homage to the racing versions if it helps. Unless you are doing the work yourself, there is no way to match the suspension upgrades and improved engine internals; I think the computers will also be a no-go for a garage swap project.