s50 vs. s52.. Need some advice.. please!
 

Hey guys.. looking to do a swap, but am not sure what I want to do just yet. I've been hearing mixed reviews about both motors and want to know what the concensus was here on the forum.. especialy for those of you who have already swapped their motors out.

So here's the deal. I have a 95' OBDI 318ti. I know the s50 is pretty much a direct bolt on, but have heard that I'd be happier with the more powerful s52. I did buy Jim's swap manual and it seems that he pushes for the 95 OBDI owners to have the s50 to make things easier. I know the s52 motor will be harder to install and more obstacles to run into, but I'm the type that would rather do the job right the first time. I don't want to have any regrets if I'm going to go through the trouble in the first place.

My brother keeps on telling me that the s50 and s52 are identical when placed in my motor bay because of the obdI restrictions; however I am not sure that this is entirely true since he's not an e36 owner (e30). I know the difference is about 10-15 hp different (to be on the conservative side), but he seems to think that my car wouldn't be able to utiltize this. Hmmm.. this is why I am here.. I need more opinions.. instead of one that thinks he knows all.

Jim mentioned a few things that I'd need different for the s52, but if you are one that pushes for the s52, can you please give me a list of things I would need different for this as opposed to the s50 swap?

I am very new to this.. have been doing hours upon hours of research (I know.. same story for anyone who is contemplating this sort of thing) and still do not have a definitive answer.:confused:

Any advice would be greatly appreciated.

Thanks! :)

Erica

(and yes, I will be posting a swap thread as soon as it commences if I get enough interest).

Well you can have the best of both worlds with a little work. I have an OBDI S52 installed in my Tis. The conversion isn't that involved and you might as well but an M50 manifold on it also. If needed I have some spare parts that you will need. Check my swap thread for more info on this conversion.


BTW the power difference isn't that big of a deal (if any) I would be more concerned with the differences in the head.

Also for software TRM is the only way to go.

hmmm... the only difference i would know about doing a OBD I S52 is that you would use the S50 engine harness. But i'm sure there other things to do...
sry, i can't be much of help.
however, i can tell you that either way you go it'll be worth it. the power difference is there and when i did it, i was thrilled.

GL with it...

Interesting thread. What about the opposite? A OBDI engine into an OBDII car? difficult?

My only piece of advise is if you decide to go with an S52, do not try to leave it obd2. Im currently working on a swap with a motor, harness, dme, trans, rear subframe, and cluster from a 99 M-roadster. Everything is just fine until you get to the nitty gritty with the motor. the small things like the wiring which is completely different and a lot of other small things that can be avoided by converting the S52 to an OBD1 setup. Check out Treehouse Racing, they have a complete conversion kit but i warn you its pretty expensive.

The s52 only puts out more torque, not hp. Doing the obd1 conversion on it utilizes te obd1 manifold which had wider runner openings which help with higher end power, hp and torque. To gain the maximum power levels requires tuning. The conversion is a little involved but nothing too difficult. As far as dropping it in all e36 engines are drop in with no issues.

Does anyone have a part number on the s50 dme/ecu? I am pushing for the S52 engine so far. I know I am going to have to use a s50 dme and wiring harnesss. I haven't had much luck finding either one of these by itself.. only people wanting to sell them with the complete engine. I've seen on a few websites, that they reference the s50 dme as being the red label 413. Can anyone confirm this? And if it is the 413, do I need the ews key?

If so, I have someone that can give me the 413 red label, but am still without the wiring harness. If you know anyone with a s50 wiring harness (complete) that wants to sell it for a reasonable price, please pm me or email directly. eboss0523@gmail.com. Also, if the dme is not the red label 413, I will need to get the dme too. If you've got these or any info, please respond. Thanks so much. :smile:

Erica

The 413 DME will work. I think even if it was out of an obd I 325, it could be still utilized by a simple chip from Turner, Active Autowerk or TRM for different maps. They also offer an EWS delete chip. I would recommend buying Jim's swap manual to answer alot of your questions before getting deep in the swap.

I've got Jim's swap manual already. While it is helpful, it doesn't answer all of my questions. He hasn't done a "dumbdown" from an obd2 to obd1.. just compiled advice from others (that is what he told me himself). I've got a red lable 413.. and think that bavarian auto recycling might have the 506 ecu for $275. I got a quote on the phone today, but forgot to make sure it was the 506.

And now for some more feedback.. would anyone be interested in another swap post? I don't mind documenting everything as long as there is enough interest. Let me know if you're someone that would like to see another swap thread. Thanks. :wink:

Erica

Simple searches on topics that have been done for many years, bfc.

http://forums.bimmerforums.com/forum...bdi+conversion

I don't have any personal interest since I don't plan to be doing a swap any time soon. However, document the process with a swap thread because it's sure to answer someone else's question at some point. Plus, you might need to refer to it some time in the future. E.g., "why did I put that there?" :biggrin:

Cliff notes: DO EEEEET!

Per Jim's swap manual, the m roadster subframe/brakes would be an ideal swap. I just grabbed a the complete suspension/subframes off of an m roadster.. it'll be here soon. :) $2K though :(

Okay.. so I'm going with the S52 OBD I conversion.

I have a quick question though. I know I need the S50 wiring harness for my S52 swap, but just found out that the one I got was from an automatic. My question now is if the automatic and manual wiring harnesses are different or if they're the same, just different DME. If anyone with some knowledge on this could help, I greatly appreciate it. Thanks.

different harnesses, but im sure you can modify it to work with a manual. or atleast thats what it seemed like when i read through the auto to manual swap on bfc

you'll have to wire up the reverse lights circuit, it will also light up the transmission idiot light in the cluster because it's trying to communicate with a computer that's not there, I'd just pull the bulb