My 1990 325is s52 swap project.

[Songj91]

Im sorry but I don't have the patients for people who post just to post. I apologize for the short temper towards those posts buy I had a point to my topic so I dont appreciate unnecessary posts about my choice of format on the forum. If u don't have anything to throw in ABOUT my topic then keep it to yourself please.

Damn 240 to the wheels sounds awesome.

Anyone ever use the same chip a I am? (TRM obd1 performance chip)
It looks pretty legit with specific tunes.

[Wanganstyle]

Finally decided to post this even tho I'm in the middle of the build. Im in OC cali & I picked up a 1990 325is about a year ago but it was a automatic & had 140k on the m20 motor. I was joking with a few friends about having my dream car...a s52 swapped e30! The joke soon became a dream come true when we went to pick up a 99 s52 motor in san Diego with around 70k. My buddies & I lugged that beast of a motor home & from that day I started buying part by part. For the tranny I needed to do a 5 speed swap (such a bitch!)so I decided to go with a 99 zf with 73k on it. The biggest hassle for me was buy everything individually to insure quality, for example, the motor & tranny were bought separately as well as the clutch & flywheel. buying every little nut & screw was a BITCH! I suggest to anyone who are planning on doing this swap to purchase motor & tranny together. Then the obd1 conversion was under way. If I had a buddy with a m50 that he wasn't using, I would have jacked all his parts but that was not the case. I bought every sensor, the wiring harness, m50 headers & cats (making CARB legal) 413 dme & tuning chip etc all one by one. After months & months of gathering parts, we were finally ready to drop it in. My buddy robin is a good friend I met on forums & I gave him my old m20 (that he rebuilt) to help me with the swap. We have the motor in the car but just need to do driveshaft, break booster & m50 manifold then all the other little stuff like my 540 MAF & 24lb injectors. I'm using a tmr obd1 chip that is tuned to m50 Mani, light weight flywheel, 540 MAF & 24lb injectors. I'll post pic when I get to a computer. Any guys out there with s52 swaps? Any smog legal? How about dynos or track times with the same set up as me? CANT WAIT TILL mines done!

FYI: This is NOT carb legal.

S52 is an OBD2 engine, to be carb legal and able to legitimately "BAR" the swapped car, you need to be installing OBD2 with the engine, or an OBD1 engine with the OBD1 brain.


Regarding CA and swaps - the transplanted engine with EVERYTHING the manufacturer made must stay as a unit. This includes DME, Carbon canister for emissions, everything.

if you want a SMOG LEGAL CA s52 harness with OBD2 to plug and play into an E30 it is avail - just email Market Motorworks; they make it for e30 swaps.

you can mod just like how you have, TRM chips S52 OBd2 brain also!! S52 obd2 brain = newer smarter brain.

[10Toes]

Do you have any pics of the car?

[Songj91]

I'll post pics with full edit. Sorry I'm a my mobile phone.
& for smog, I thought there u could have ref check it out?? Or I was thinking about swinging it by an old friend of mine if you kno what I mean. Haha

[Pudmunkie]

I'll post pics with full edit. Sorry I'm a my mobile phone.
& for smog, I thought there u could have ref check it out?? Or I was thinking about swinging it by an old friend of mine if you kno what I mean. Haha

I know you just publicly proposed circumventing the law, Billy Badass.

Sent from {smartphone;}

[Wanganstyle]

I'll post pics with full edit. Sorry I'm a my mobile phone.
& for smog, I thought there u could have ref check it out?? Or I was thinking about swinging it by an old friend of mine if you kno what I mean. Haha

IF your car was done SMOG LEGAL, then you can just drive the car to the BAR referee and they will give you legal swap papers- then the CHP cannot say anything about it. no need to play shady smog games.

I'm not sure you read what was posted earlier- please read it again, engine AND ecu must stay as a PAIR. OBD2 stays obd2. if you convert an OBD2 to obd1 or OBD1 engine to OBD2, it is ILLEGAL in This state (California).

[pandaboo911]

IF your car was done SMOG LEGAL, then you can just drive the car to the BAR referee and they will give you legal swap papers- then the CHP cannot say anything about it. no need to play shady smog games.

I'm not sure you read what was posted earlier- please read it again, engine AND ecu must stay as a PAIR. OBD2 stays obd2. if you convert an OBD2 to obd1 or OBD1 engine to OBD2, it is ILLEGAL in This state (California).

Actually if the car was sold from the factory as obd1, the engine upgrade law limits you to using obd1 engines (doesn't really make sense, obd2 is cleaner). So technically an s52US isnt legal in an e30 no matter what.

Generally people do an obd1 swap, and as a result the s52 looks almost identical to the s50US, an obd1 engine. Another way of doing it is to just run a complete obd1 exhaust, and hope that the referee can't spot the obd2 intake manifold etc..

Either way youre fooling the referee into passing it as an s50 when in reality it isn't. As long as he runs a stock looking obd1 exhaust, full e36 evap system, and a stock intake (CA legal k&n cone filter), he should pass no problem. Also your CEL needs to function properly.

[JrCamacho]

Actually if the car was sold from the factory as obd1, the engine upgrade law limits you to using obd1 engines (doesn't really make sense, obd2 is cleaner). So technically an s52US isnt legal in an e30 no matter what.

Generally people do an obd1 swap, and as a result the s52 looks almost identical to the s50US, an obd1 engine. Another way of doing it is to just run a complete obd1 exhaust, and hope that the referee can't spot the obd2 intake manifold etc..

Either way youre fooling the referee into passing it as an s50 when in reality it isn't. As long as he runs a stock looking obd1 exhaust, full e36 evap system, and a stock intake (CA legal k&n cone filter), he should pass no problem. Also your CEL needs to function properly.

Thanks for clearing this up, i have been looking for an answer, and you sir have done it.

[Wanganstyle]

Actually if the car was sold from the factory as obd1, the engine upgrade law limits you to using obd1 engines (doesn't really make sense, obd2 is cleaner). So technically an s52US isnt legal in an e30 no matter what.

100% incorrect info. you can bar any LSX swapped E36 (obd1 or 2 chassis). also BAR a LSX swapped bmw 2002. or a toyota 2jz obd2 swapped camaro or datsun 240z. These have all been done in california.



Here is a bar sticker of a 80's toyota with 2001 honda transplant. LEGAL, BAR certified in California.






READ before posting incorrect things:)
California BAR website:

http://www.bar.ca.gov/80_BARResources/07_AutoRepair/Engine_Change_Guidelines.html

quote from california BAR website:


COMPUTER CONTROLS
If a computer–controlled engine is installed in a non–computerized vehicle, the "CHECK ENGINE" light, the Original Equipment Manufacturer (OEM) diagnostic link, and all sensors, switches, and wiring harnesses needed to make the system fully functional must also be installed.

this clearly states that you can install a computer control engine (i.e. obd 1/2 or Can-BUS) into a NON-computerized vehicle (i.e. 1967 camaro). The full system needs to be installed, functioning properly. No specification to OBD1/2/whatever. Stating a non-computerized (carburated) vehicle can install a computer controlled engine is as open game as it gets.

Generally people do an obd1 swap, and as a result the s52 looks almost identical to the s50US, an obd1 engine. Another way of doing it is to just run a complete obd1 exhaust, and hope that the referee can't spot the obd2 intake manifold etc..

And the average public likes to hodgepodge and do illegal modifications to their car because they are lazy to READ the California BAR website or simply dont mind having an illegal engine swap setup. Junk yard poop everything with used sensors; this is the R3v way.

No need to obd1 swap to a dumber brain.... Level up the skills and install the complete S52 brain+emissions control + air pump - its not hard to do, if you cant wire things send it to MMW to get done professionally. This also = perfect BMW OEM Tune for s52.......nobody tunes a bmw engine more reliably than the factory does.

[Songj91]

Thanks pandaboo911. Ya I'm running stock headers, down pipe & exhaust so the motor looks obd1. U think I can get it to pass? Don't most places just pipe a obd1 car & then ur off?