Build Thread: Korman 535i Turbo 2.0

[Binjammin]

If you're trying to keep the car an automatic, swap your 4hp22eh to a 4hp22h. It's an all hydraulic box, no electronic controls. Get one from an e28 535.

[E34DIYer]

That is not a bad idea!! That never even occurred to me. Probably sort of rare, but I imagine relatively un-desirable?

[Binjammin]

Actually, I think I'm wrong about that. I think the e28 535 got the 4hp22eh. What you need to do is find the 4hp22h from an e34 525 with an m20 in it. The bellhousings are removable, and you can reuse the bellhousing from your m30 4hp22eh. There's info on how to do this all over, just look around for 4hp22eh A Clutch pack failure and rebuilds. You won't need to go anywhere near that deep just swapping over a bellhousing, but those rebuild threads will include that detail.

[dangerwillrbnsn]

Non-eh 4hp22 transmissions can be found in the e28 535 (except the IS). I'm not sure what other cars they came in. I'm 99% certain that a m20 transmission will NOT bolt up to your m30 motor... I think there are some e34 535's with the non-eh trans as well. I'm sure there are probly 2-3 in my local yard right now @ $250 a piece.

[E34DIYer]

The amount of hassle involved is getting dangerously close to just sucking it up and swapping in a 5-speed.

[Binjammin]

Non-eh 4hp22 transmissions can be found in the e28 535 (except the IS). I'm not sure what other cars they came in. I'm 99% certain that a m30 transmission will NOT bolt up to your m30 motor... I think there are some e34 535's with the non-eh trans as well. I'm sure there are probly 2-3 in my local yard right now @ $250 a piece.

I don't know what you mean by "a m30 transmission will NOT bolt up to your m30 motor" however if you mean M20 transmission, you are correct, which is why I specified swapping an m30 bellhousing onto an m20 4hp22h. That WILL bolt up and function in the car.

[dangerwillrbnsn]

I don't know what you mean by "a m30 transmission will NOT bolt up to your m30 motor" however if you mean M20 transmission, you are correct, which is why I specified swapping an m30 bellhousing onto an m20 4hp22h. That WILL bolt up and function in the car.

Apologies, my fingers sometimes move more quickly than my brain can keep up with. But you are correct.

[Binjammin]

Apologies, my fingers sometimes move more quickly than my brain can keep up with. But you are correct.

Ain't no thang...

[E34GRRR]

Hi Guys!
I'm new to the forum and just bought myself an 1990 E34 535i/A. I'd like the end result to be Turbo'd to 400-500 HP, Zeemax Widebody Conversion, dropped with gunmetal 18s or 19s. From what I've been reading over the years the M30 with stock internals can be reliable up to 500 HP. This has been a dream/goal of mine for at least 15 years. I finally am in a position to begin the project.
I'm VERY satisifed that I found this thread as I'm trying to learn as much as I can about what needs to happen to Turbo the Auto. From my understanding the stock auto only handles 300 lb/ft.
Is the best plan to just swap the Auto for a 5 speed? I plan on dumping a couple grand a month into my baby until she's complete.
Any help is greatly appreciated!

Alan

[Binjammin]

Hi Guys!
I'm new to the forum and just bought myself an 1990 E34 535i/A. I'd like the end result to be Turbo'd to 400-500 HP, Zeemax Widebody Conversion, dropped with gunmetal 18s or 19s. From what I've been reading over the years the M30 with stock internals can be reliable up to 500 HP. This has been a dream/goal of mine for at least 15 years. I finally am in a position to begin the project.
I'm VERY satisifed that I found this thread as I'm trying to learn as much as I can about what needs to happen to Turbo the Auto. From my understanding the stock auto only handles 300 lb/ft.
Is the best plan to just swap the Auto for a 5 speed? I plan on dumping a couple grand a month into my baby until she's complete.
Any help is greatly appreciated!

Alan

Alan, get ready for a reality check. I don't know how you plan to perform a widebody conversion, but assuming you have the money to do that we can assume you have the money to get an m30 to 500hp. For the record, it's a big jump from 400-500 hp, and you'll need to plan your build accordingly before you start buying parts for one goal and attempting to hit the next goal with them.

For the record, you won't see 500hp on a stock m30. If you want to boost an m30, go to the FI subforum and find member good & tight, he's built an m30 powered e30 pushing right around your goals, uh... on a budget. You'll find the rest of the time, that power number is very high to attempt on an archaic motor like the m30. If you really want to make close to that, swap to an m50 and your options open up.

[E34GRRR]

Alan, get ready for a reality check. I don't know how you plan to perform a widebody conversion, but assuming you have the money to do that we can assume you have the money to get an m30 to 500hp. For the record, it's a big jump from 400-500 hp, and you'll need to plan your build accordingly before you start buying parts for one goal and attempting to hit the next goal with them.

For the record, you won't see 500hp on a stock m30. If you want to boost an m30, go to the FI subforum and find member good & tight, he's built an m30 powered e30 pushing right around your goals, uh... on a budget. You'll find the rest of the time, that power number is very high to attempt on an archaic motor like the m30. If you really want to make close to that, swap to an m50 and your options open up.

Widebody conversions are on EBay every once in a while. I could just order it from Zeemax directly but shipping across the pond will be pricey. $4k just for the kit. Drops vehicle weight 150 lbs too.

I've read 21 psi with 36 lb injectors was good for 518hp on stock internals. I don't need 500. Anything over 400 would be solid and cool with me . I've been in touch with Todd over at TCD. Hopefully he can help guide me down the path of Turbo Ecstacy.

Thanks for the referral to Good & Tight. I'll definitely be catching up on some reading.

*Edit: $4578.68 shipped to New Hampshire. £2599.00 for the kit and £450.00 to pack/ship.

[E34DIYer]

E34GRRR:
First, glad to hear that my thread is useful to someone! Regarding your build: As I understand it, the M30 guts are fine for turbocharging to 500HP. I think the 12-valve cylinder head is one of the main restrictions, and sadly you can't easily swap a 24V head (S38, M88/3) onto the M30B35 bottom end. You can make your HP goal with enough boost, but you'll want good knock detection and possibly meth/water injection to quench the combustion chambers.

Your 36lb injectors will be way too small though, unless you up the pressure to like 60psi. At standard 40-45psi, you'd be better off with 40-50lb injectors (like the 42lb Bosch injectors I was going to use).

What will you do for engine management? W.A.R.? Megasquirt? VEMS? Or something pricier?

If my powdercoated intake or oil pan sells, I may take my 535i/A to the dyno just to see what it's putting down. My turbo is only pushing 4.5psi on the stock AFM, but it's definitely a bit quicker than stock!

[E34GRRR]

E34GRRR:
First, glad to hear that my thread is useful to someone! Regarding your build: As I understand it, the M30 guts are fine for turbocharging to 500HP. I think the 12-valve cylinder head is one of the main restrictions, and sadly you can't easily swap a 24V head (S38, M88/3) onto the M30B35 bottom end. You can make your HP goal with enough boost, but you'll want good knock detection and possibly meth/water injection to quench the combustion chambers.

Your 36lb injectors will be way too small though, unless you up the pressure to like 60psi. At standard 40-45psi, you'd be better off with 40-50lb injectors (like the 42lb Bosch injectors I was going to use).

What will you do for engine management? W.A.R.? Megasquirt? VEMS? Or something pricier?

If my powdercoated intake or oil pan sells, I may take my 535i/A to the dyno just to see what it's putting down. My turbo is only pushing 4.5psi on the stock AFM, but it's definitely a bit quicker than stock!

I'm not sure about engine management hence joining the forums. Id like a reliable 4-450hp. Thanks for the insight on the injectors. I'd definitely be interested to know how the dyno goes. I won't have the funds for the TCD kit for another few months.

On a different note I cant keep the ol' girl from running hot. I flipped in a new thermostat and belts and it went away but today it started creepin up to the red again. I know from my 3 E30s that they tend to get warm when idling but this seems to be different. And, I'm not blowing hot air either. Heater control valve?

[E34GRRR]

E34GRRR:
First, glad to hear that my thread is useful to someone! Regarding your build: As I understand it, the M30 guts are fine for turbocharging to 500HP. I think the 12-valve cylinder head is one of the main restrictions, and sadly you can't easily swap a 24V head (S38, M88/3) onto the M30B35 bottom end. You can make your HP goal with enough boost, but you'll want good knock detection and possibly meth/water injection to quench the combustion chambers.

Your 36lb injectors will be way too small though, unless you up the pressure to like 60psi. At standard 40-45psi, you'd be better off with 40-50lb injectors (like the 42lb Bosch injectors I was going to use).

What will you do for engine management? W.A.R.? Megasquirt? VEMS? Or something pricier?

If my powdercoated intake or oil pan sells, I may take my 535i/A to the dyno just to see what it's putting down. My turbo is only pushing 4.5psi on the stock AFM, but it's definitely a bit quicker than stock!

I'm not sure about engine management hence joining the forums. Id like a reliable 4-450hp. Thanks for the insight on the injectors. I'd definitely be interested to know how the dyno goes. I won't have the funds for the TCD kit for another few months.

On a different note I cant keep the ol' girl from running hot. I flipped in a new thermostat and belts and it went away but today it started creepin up to the red again. I know from my 3 E30s that they tend to get warm when idling but this seems to be different. And, I'm not blowing hot air either. Heater control valve?

[Binjammin]

Guys, seriously, it's going to take more than you think to hit even 400whp on an m30. Don't think I'm crapping around in here, bring it to the FI subforum and ask in there. Don't go believing everything you read on the internet.

[Binjammin]

Guys, seriously, it's going to take more than you think to hit even 400whp on an m30. Don't think I'm crapping around in here, bring it to the FI subforum and ask in there. Don't go believing everything you read on the internet.

[E34GRRR]

Guys, seriously, it's going to take more than you think to hit even 400whp on an m30. Don't think I'm crapping around in here, bring it to the FI subforum and ask in there. Don't go believing everything you read on the internet.

"e34biturbo" posted posted pics of his dynos. Go to .com/forum/showthread.php?t=1180201
Stock injectors, stock ecu, 10psi: 315hp / 336 lb/ft
stock internals, standalone ecu, 36 lb injectors 21 psi: 521.5 hp 544.4 lb/ft

[Binjammin]

"e34biturbo" posted posted pics of his dynos. Go to .com/forum/showthread.php?t=1180201
Stock injectors, stock ecu, 10psi: 315hp / 336 lb/ft
stock internals, standalone ecu, 36 lb injectors 21 psi: 521.5 hp 544.4 lb/ft

And Redfive went with a fully built motor and barely cracked 400whp. IIRC it was below that where he ended up setting his tune, and that was at 18psi. There's a lot to consider when calculating what you're going for, including what turbo you'll be using. You can get 21psi out of a t25, but that won't flow anywhere near the cfm that a larger, more efficient turbo will.

Seriously, go post a thread in the FI subforum. Ask around and see what people are building and have built. One person's postings on a forum should absolutely NOT be taken as gospel.

[E34DIYer]

Do try posting a thread in the FI forum, but feel free to keep an eye on this thread too. I'll document things as I try them. For now I'm looking into piggyback options that would let me retain the stock ECU for now. e34biturbo isn't too far form me, so we might be able to meet up and discuss things in person.

EDIT: My current goal is to take the car to 300whp, then go from there. I'll remove restrictions as I encounter them.

[E34DIYer]

Well, I may be saying goodbye to my 535i project... I may be purchasing an E24 M6 in the next couple of weeks, in which case my 535i would go up for sale. Will probably ask $4500.

[E34DIYer]

Long-overdue update: Bought the 1988 M6, love the styling but miss the agility of my 535i, so I'm selling the M6 and keeping the 5'er! On a related note, my 535i turbo has developed an interesting new issue... The other day I was driving down I-185 when I slowed for a tollbooth. As the RPMs dropped below 1200, the engine stalled out. I rolled to a stop at the booth, paid the toll, and managed to coax the engine back to life with deft feathering of the gas pedal. But I couldn't let the RPMs drop below 1200 or it'd stall again - so for the rest of the two-hour drive, I had to use both feet at stoplights to keep the engine revv'd while sitting still. Finally got home, popped the hood, and saw that the idle control valve had popped out of the intake boot! I promptly reinserted it, at which point the engine ran normally.

Actually, I noticed that the engine's running better than normal... the turbo has been whistling more loudly, and there's definitely more power all of a sudden. But the ICV keeps popping out! I'm going to add a hose clamp to keep the ICV on the intake boot, but I can't help but wonder if the turbo's wastegate has become stuck in the "closed" position...? May hook up a vacuum gauge this weekend and see where I'm at. I'm still running the stock AFM (with tweaks from Korman Auto for the T25 turbo), so I need to be careful not to over-boost beyond the current setup. Anyway, interesting update.

[JesterMX6]

yeah i'd get a boost gauge on there asap if you haven't already.

also, all turbo cars should have hose clamps on everything. or else you end up popping off the loosest hose of the bunch (which in ur case ended up being the ICV lol).

glad to hear you stuck with the 535i.

[Binjammin]

Absolutely everything should be clamped down, and you shouldn't be driving it without a boost gauge either. Surest way to kill something.

[E34DIYer]

Car was professionally tuned & limited for specific boost, ran fine until this issue popped up (15 years later). But it's back to normal now. I suspect the wastegate is seizing, as it now seems stuck in the "open" position and the car is under-powered. On an unrelated note, I also ordered an Armor Garage epoxy floor kit. Tired of the grimy stains on the floor. Will snap pics when done.

[BigM62]

I have always respected Ray Korman's products. Great find!