Getting ready BMW E30 engine swap

Life has been so busy lately. I haven’t had much time to work on my BMW E30 engine swap or this blog. I’m excited about it and wish I had more time to wrench away. It’s barely driveable and had some big issues. For starters a loud clicking noise coming from the rear. Second, when installing the exhaust from the donor car I noticed a broken motor mount. This was tilting the engine to a point low enough to not let me pull out the exhaust. This was also the cause of the low power in the already slow BMW 325e engine. Third was little to no braking power. I had a lot of work to do.




First, I purchased some new e30 motor mounts on eBay. It took about three days to arrive. They were fairly easy to change out once they arrived. They are held on by one bolt on top and bottom of each engine mount. All I had to do was loosen the bolts. Place a jack and block of wood under the oil pan. Then start jacking the engine up. Go very slowly and look for any hoses, lines or wires that may be stretching. If you see this, STOP, and address whatever may be stretching. Then keep jacking just until you have enough room to pull the old motor mounts from between the engine and the chassis. BE CAREFUL THOUGH, as the engine is only supported by the jack. In some cases it may be helpful to put jack stands under the wood while the engine is up. This will provide extra safety. Now the new motor mounts easily slide in. Loosely connect the bolts. Then slowly lower the engine so bolts slide through the hole on the metal E30 motor mount arms. Then you can torque to spec. Which is 30ft./lbs



The exhaust from the donor car bolted right up and was easy to install also. There are 6 nuts that connect the exhaust to the headers. Some are a tight reach but with some patients go on fairly easy.  Then you need to connect the E30 o2 sensor to the wiring harness. Since the original exhaust was a poorly done straight pipe I had to use all the exhaust hanging parts form the donor car. I also had to cut out some cruddy wire hangers the original owner used to attach the 3″ straight pipe. There is a rubber hanger in the middle and two at the end near the muffler. These were both easy to attach.




Finally, I was able to drive it again. There was still the issue with the clicking noise. At first, I thought It was coming from the transmission. I decided to tackle the brake problem. When ordering the motor mounts for the e30 I also ordered some new brake lines and parts to rebuild the calipers. While installing the new brake lines I found another problem. The springs that hold the parking brakes together were broke. This resulted in the parking brakes constantly rubbing against the e30’s brake rotor. The spring clicking as the wheel turned. I had to once again wait for parts. In the meantime, I cleaned and rebuilt the brake calipers. I installed the new red brake lines and tried to bleed the system. No luck. Apparently, the master cylinder was bad. I ordered a new one and had to wait again. Once the new parts arrived. I cleaned up and installed the parking brake parts. Bench bleed the brake master cylinder. Then bleed the brake lines. I wish I had documented it better.


That took about a month between work and other responsibilities consuming my car time. Finally, though the e30 was drivable again. It seemed to be running good. I would drive short distances careful to avoid cops or an accident. I decided to head for the local DMV. To my amazement the 1985 BMW 325e E30 project I’ve been working so hard on passed emissions. I was able to register it in my state. I was very happy. After 7 months I was able to drive my E30 legally. I could finally drive around town without worrying about the police and suffer the consequences of a big ticket or fine. Another pretty cool thing happened while browsing the Facebook marketplace. I was able to score an awesome set of wheels and tires. A nice upgrade to the stock wheels. The new wheels were 16 x 8.5 and looked sweet. The man I purchase to from gave me a really good deal. He was asking $355 he agreed to sell them for $300. They do have a couple scratches and dings. Most notably a small bend to the lip. It was an awesome deal. Even though I need the money for other parts. I couldn’t pass it up. They look way better than the stock bottle cap BMW e30 rims. I think they really make the car look nice. Here are some before and after pics.

My bmw e30 with stock wheels.
A side view with the stock wheels
bmw e30
A side view of my 1985 BMW 325e with the new wheels. 16×8.5



I’m developing a plan to start the engine swap soon. I have been collecting the last of the e30 parts I need. I will be fully documenting the swap. I will provide a breakdown of the BMW M30B35 engine I purchased. As well as provide a detailed explication of what I’m doing. I’m still a novice mechanic in my opinion and my knowledge is limited. Google and Youtube are great teachers though. Hopefully, this journal will help me as well as others who attempt this M30B35 swap. From the research I’ve already completed It seems fairly straightforward. I will also document my progress in this e30 m30b35 swap guide. I’m excited but still have a lot to do. Work and funds, as usual, provide an obstruction to progress. However, I do have a goal of completing the swap by the end of the year. I don’t want to rush but I also want it to be done sooner rather than later. Recently I purchased a manual pedal unit for the manual conversion. I also purchased a BMW c101 connector to make an adapter for the m30 wire harness. I still need a few parts and have been debating on getting either another parts car or purchasing the parts separately. Although I plan to add a turbo and install a mega squirt wasted spark setup in the future. For now, I am going to just use the original m30b35 engine computer and wiring.


BMW M30b35 engine
The BMW m30b35 engine I plan to swap into my E30. Its from a 1993 bmw 535i


1989 bmw 535i e34
1989 BMW 535i E34 Parts car.



I still need a few parts to complete the basic M30 swap. There might be more I am unaware of. I am debating on if I should purchase the majority of them individually or purchase another E30 parts car. I recently saw one on Craig’s list for $700. Unfortunately, it’s about a 2 hours away and I don’t have access to a truck to tow it. It had some nice decent sport seats and the manual parts I needed. I could also make some money flipping the other parts. I’m unsure. I also am tight on funds so It’s probably a no go. This is a list of the minimal amount of parts I will need.

  • Spark plug wires for the m30b35 engine.
  • Front subframe reinforcement parts from Garagistic’s
  • Shifting selector rod??
  • The right size radiator.
  • other unknown.
  • turbo parts (Future)
  • Megasquirt (Future)
  • New seats (Future)
  • New front and rear bumper (future)
  • ?????


There are also quite a few things I need to do before I would feel comfortable starting the swap. My garage is a mess and If I’m going to be documenting this for other and myself I would need to get more organized and prepared.

  • There are still quite a few things I also need to do in the garage before I start. The first would be to finish building my workbench and organize my tools. If I am going to be fully documenting the e30 m30b35 swap then I will need to be very organized.
  • I need to get some peg board and organize all my tools.
  • I still need to sell an excess amount of computer parts I have laying around. This will help fund some e30 parts.
  • The engine stand I purchased is still in the box and needs to be assembled.
  • I need to decide which side of the garage I will park the car during the swap. Moving the car will be quite difficult once I have it apart and parts organized.
  • I want to develop a system in which I disassemble or assemble apart and document it here before I proceed to the next step.
  • Move a computer into the garage and internet signal.


Still have a lot to do before I can start the swap


I really can’t wait to get my other projects out of the way so I can start on the engine swap. I have a big list of things to do prior to the E30 swap.  In my spare time at night I’ve been doing a lot of research and reading. Looking at other builds and tutorials. Dreaming about rolling around in my turbo’ed E30. There are still a few things I have no clue how to do. I don’t know how to set up a turbo, mega squirt or even an engine swap for that matter. I’m still confident that I will be able to do the engine swap with minimal problems.  The electrical being the largest hurdle. I found some electrical diagrams that seem to make sense and its just a matter of connecting the correct wires together.  I would also like to keep the ac and get that working too because of the hot AZ desert sun. I’ve also debated on and off if I want to finish the swap or not. As a person who likes to flip cars and trade other assets I could put the old wheels on and sell it for a profit. Sell the m30b35 engine too. Then move on to another project. I’m 90% set on the engine swap and pimping this e30 out with new Interior, sound system, turbo, mega squirt, a wasted spark set up, and an air suspension system. Of course, my vision is bigger than my bank account at the moment so I will have to be patient.  I came across this e30 photo while researching that is so pimp. It’s similar to what I plan to do with my interior. I wish I knew who’s build this was and had more pictures because it is so sic. Can’t wait. If you made it this far thanks for reading. I’ll be working on this soon and have more updates. TO BE CONTINUED….


e30 white leather
This is a sick e30 interior. This is the look ill be shooting for on my e30 build. 
Bad E30 interior
A view of the horrible e30 seats. Still needs a lot of work
The horrible condition of the E30 comfort seats in my 1958 BMW 325e.