My e34 swap, mods, experiences and advice

[bimmerd00d]

Thanks Brandon, I didn't know anything about the details of the S52 powerband, and that makes a lot of sense. I really appreciate the information, I am glad you took the time to post.

Now we need some comparison sheets between the S50/S52 and S38. It would be interesting to see how they line up to eachother.

[Brandon J]

You cannot do a S38 conversion unless you have a donor M5. There are way too many parts to swap. You would need the wiring harness, tranny, driveshaft, radiator, all ancillaries, intake, full exhaust, etc. etc.

Now if you have an M50tu already, all you need is the M3 engine longblock and a chip. Obviously there might be things you want to replace (wear parts) or you may choose to use the larger injectors of the OBDII engines, but that is nothing compared to all the specific parts you need for a S38.

As far as engines are concerned, the S52 is more reliable than the S50. It came with stronger valve springs and retainers. These are known weak points in the S50 valvetrain. It is also difficult to compare an OBDI 3.0L to the OBDII 3.2L because the 3.2L will be converted to OBDI. I say, go for the extra displacement. No replacement for displacement. The extra .2L does help when using it as a base for adding power. Oh btw, I am talking about the US versions.

Thanks I've always been wondering about that car. Nice work. I'm thinking about an engine conversion but like repent I'm undecided between the S50 ofr the S38. Theres plenty of power to be made out of the S50 and isnt the S50 alittle more reliable and better on gas mileage?

[Sam-Son]

You cannot do a S38 conversion unless you have a donor M5. There are way too many parts to swap. You would need the wiring harness, tranny, driveshaft, radiator, all ancillaries, intake, full exhaust, etc. etc.

Now if you have an M50tu already, all you need is the M3 engine longblock and a chip. Obviously there might be things you want to replace (wear parts) or you may choose to use the larger injectors of the OBDII engines, but that is nothing compared to all the specific parts you need for a S38.

As far as engines are concerned, the S52 is more reliable than the S50. It came with stronger valve springs and retainers. These are known weak points in the S50 valvetrain. It is also difficult to compare an OBDI 3.0L to the OBDII 3.2L because the 3.2L will be converted to OBDI. I say, go for the extra displacement. No replacement for displacement. The extra .2L does help when using it as a base for adding power. Oh btw, I am talking about the US versions.

Wow as always a great bunch of useful info. Really thank you

[Sam-Son]

Brandon I was wondering if you could tell me a little more about the mods you did to the 2.5 M50. It seems that modding the M50 will be a little more affordable at this point. What kinda HP did you get and was it reliable HP? also What did those mods run you if you don't mind my asking?
Thanks
-Mike

[Brandon J]

Brandon I was wondering if you could tell me a little more about the mods you did to the 2.5 M50. It seems that modding the M50 will be a little more affordable at this point. What kinda HP did you get and was it reliable HP? also What did those mods run you if you don't mind my asking?
Thanks
-Mike

Well, look-up how much S50 camshafts and a performance chip cost and there are your parts. I would say, there was a very nice bump in power in every rpm with the cams and chip. I know Turner Motorsport had that package for a while. With all my mods I listed in this thread, I was around 240hp, but not the same torque as an M3. I would say, go for the S50 cams, vlalve springs, retainers, and chip. If you want more power, then wait and just do the engine swap. It was a fun engine, but I did have to push it hard and work the clutch a lot to get to the upper rpms all the time. I always tell people to wait and save-up for the engine swap. By the time you spend on camshafts, valve springs, retainers, and a chip, you are more than halfway in price to an engine. Knowing how power is addictive, just doing this cam upgrade will definitely make you want more.

I did not like the lightweight flywheel for the street. It was too noisy and I lost lower end torque because of less mass and inertia. A 3.46LS is a nice upgrade, but it is a little short. Unless you spin your engine to ~7200rpm, you won't reach 60mph in 2nd gear. So, just a tad too short for the street. After having these mods, I was exhausted and realized that this isn't a Honda engine that I have to spin up for the power. It turned into that.

If you must do an upgrade, I mean a must and can't afford or find a M3 engine, then go for the 2.8L swap with M3 cams. Get that extra torque from displacement and then add the camshaft, retainers, valve springs, chip. That is a good monetary compromise. Just remember that with this, you are 3/4 of the way to a whole M3 engine.

[Sam-Son]

As always Brandon I thank you very much for that wealth of knowledge and heldful info

[Booster]

Thanks Brandon, Lots of good info there. I still think I'll join JonK and do a top mount single turbo and MegaSquirt on the Non Vanos M50.All my cars are Turbo'd except the 525I and I just love the boosted feel.

What did you end up doing with your swapped cams,springs etc ?
Cheers,Vinny

[Brandon J]

Thanks Brandon, Lots of good info there. I still think I'll join JonK and do a top mount single turbo and MegaSquirt on the Non Vanos M50.All my cars are Turbo'd except the 525I and I just love the boosted feel.

What did you end up doing with your swapped cams,springs etc ?
Cheers,Vinny

I got rid of those years ago when I did the swap. Good luck with your turbo project.

[Sam-Son]

Brandon could you tell me a little bit more about the intake setup you had on the M50?

[healtoeit]

Brandon could you tell me a little bit more about the intake setup you had on the M50?

Go to my "My CAI set up" thread

It's not the one he had but he comments on it and so do a bunch of other guys here.

Btw, why isn't this a sticky anymore?