New sportster builder after advice

[mcramsay]

Hey guys, I posted up a few months ago that I was looking to buy and build a sportster kit! Well I am now the owner of a brand new kit! I completely forgot about my last thread so I figured I would start a new one and give every one an update and ask advice!

Basically due to marlins situation at the moment I decided to order al parts from them that I could, so I have the chassis, all the body work and suspension, interior trim kit and a new style roof aswell, all sat out in the garage to be built!

I am going to use the m3 s50 b32 engine and was wondering if there was any one that has gone this route and who I can ask advice! Basically from the wiring diagrams I have studied and advice I have been given I will need the ecu,ews boxes and key and transponder all from the same car. It looks like the engine loom has a main relay and fuel pump relay in it which go to the engine to main loom on the x20 connector? Any wiring advice would be much appreciated things like is it possible to wire in the obd connector and engine warning light? And will the ecu go into safe mode if I do not have and on the car?

[MartinClan]

Welcome to the unique club of Sportster builders.

I can't help you with the engine I'm afraid - I used an M20 which has relatively simple electronics.

I re-used as much of the original BMW wiring loom as I could. I spent one winter removing all the stuff I didn't need (about 75% of it). But it has big benefits in the long term as you keep the standard wiring colours and can retain much of the original switchgear and fusebox without having to worry too much about exactly how its wired.

I wasn't aware of any problems at Marlin. Would someone care to enlighten me?

Cheers, Robin

[Mike]

Originally Posted by mcramsay

Hey guys, I posted up a few months ago that I was looking to buy and build a sportster kit! Well I am now the owner of a brand new kit! I completely forgot about my last thread so I figured I would start a new one and give every one an update and ask advice!

Basically due to marlins situation at the moment I decided to order al parts from them that I could, so I have the chassis, all the body work and suspension, interior trim kit and a new style roof aswell, all sat out in the garage to be built!

I am going to use the m3 s50 b32 engine and was wondering if there was any one that has gone this route and who I can ask advice! Basically from the wiring diagrams I have studied and advice I have been given I will need the ecu,ews boxes and key and transponder all from the same car. It looks like the engine loom has a main relay and fuel pump relay in it which go to the engine to main loom on the x20 connector? Any wiring advice would be much appreciated things like is it possible to wire in the obd connector and engine warning light? And will the ecu go into safe mode if I do not have and on the car?

Hi Mcramsay

Welcome to MAKC, and particularly the Marlin section.

I can't help with the Sportster side of your build as I am about to complete IVA with my Cabrio, so am not directly going to help, but I do have a BMW M50TUb25 engine, so did a lot of research about the electrics, and I have photos of your proposed engine in a Sportster!





This was built by John Clemence. I'll PM his email for you to try to make contact.

Do you know if the S50 wiring is similar to the M50, as it is M50 derived?
If it is, I needed only 7 wires to run my engine including fuel relay, and did not require keys, transponders, or the binnacle guages to make mine work.
If you would like I can email a spreadsheet of the 7 X20 wires required to run the M50 that Nigel Beats forwarded to me and solved my wiring concerns?

Good luck with your build and have fun.

Mike
PS - just don't take as long as I have!!

[NigelB]

Welcome to the forum and congratulations on a great choice of kit car. It's not the easiest. You don't get the greatest support from the supplier and it's going to take a whole lot longer than the hours Marlin quote on their website. But if you like a challenge, you enjoy problem solving and your after a traditional sports car with a little more style, comfort and practicality than the average seven clone, then you've made the right choice. And with the help and support you can get from this forum when you need it, you'll end up with a great car.

I went down the M50B25 route which eliminates most of the immobiliser issues and the wiring was quite straight forward. I barely touched the engine wiring loom other than to move the alternator to the RHS of the engine. I made up my own main loom based on the CBS distribution panel plus some additional relays and bus bars and there were only 8 wires needed to connect to the X20 engine loom interface. (It was originally seven but then both Mike and I realised we needed a 12V supply to the reversing light switch!!)

I don't know how the M50B25 compares with the S50 but I believe that Rob Nichol (Bobnic) used the same engine. No doubt he will pop up here and can give you some advice.

There's a whole load of built threads on line as well which will be useful. Check these out when you can

http://www.flickr.com/photos/58068042@N07/
http://www.flickr.com/photos/mikes_bmw_marlin_cabrio/
http://www.flickr.com/photos/peters-bmwmarlin/
http://www.msportster.co.uk/
http://www.greatoldone.co.uk/
http://www.flickr.com/photos/99543879@N03/

and last, but not least..............!!

http://www.flickr.com/photos/marlinbuild/

Keep us up to date with progress. I was down at Marlin at the end of October and there was a pre-powder coat chassis there. If you've only just taken delivery it may well have been yours.

Best of luck and don't forget. Just ask.

Nigel