Motor Swap E3?

[Fernando Gutierrez]

Hey Guy!

I recently aquirred a 1972 BMW Bavaria,
it has been sitting for 12 years by the previous owner,
but he purchased it from someone who had it in storage,
I am new to this forum and I'm curious what you guys think I should do with the motor,

current options are to check to make sure its not "Frozen" or seized,
or swap another M30, but i called a local shop and my quote for a fuel injected m30 was over 10k,

I actually am an e3o guy, and I have swapped a m20 in my previous car for about 500$

can anyone give me some insight or advice I would greatly appreciate it !

I will post pics soon as well!

 

[naccer]

An M30 in all of its various incarnations is a pretty good engine. Find a beater / junk car - any engine variant from the 60's through the early 90's will bolt in with some fiddling. Arguments can be made for carbs, or ljet or motronic, etc. If it's been sitting it might simply be the first thing you find that works.

Al Taylor on this forum usually has engines for sale, I don't want to quote for him, but I'd imagine a 500-1500 charge depending on the displacement, accessories, and year / type of head etc for a good running M30 swap. We've seen several donor cars on the side for 500 -1500 bucks...they're out there if you have a nice body / interior.

But before all of that, don't panic, I think that quote would be appropriate for a shop converting a car to a new built 3.5 motronic, 5 speed, and having all systems updated with working AC...etc.

Your '72 should be a carb car, make sure it has some oil / coolant in it, see if you can turn it over, then see if you can get it to fire up with some starter fluid in the carbs. Check the points, gap the plugs, then if it'll run go from there on jetting it, tuning it, valve adjustment and you may have a decent motor in there...

If it's locked, pull the spark plugs, squirt marvel mystery oil in the plug holes wait a few days and try to turn over again. If it turns freely remember to change the oil before running it.

E3 life...

 

[HB Chris]

Doing a b35 motor for $10K is very reasonable and I would think hard to find one for that price, but don't expect tranny and A/C for that price either.

 

[Mike Goble]

I put an M30B35 in my Bav for about $200 total, such is the value of doing your own work.

 

[Fernando Gutierrez]

Naccer,
thanks for your input! Luckily I have a few close by junkyards to source our a good m30 from a later model,
but I do have a head that came out out a b35 so i think with just carb adjustment that later model head should work on my current block,
I have an engine stand and a puller so I'm ready to do either, but if i just pul out my motor I'm most likely going to take my time and replace most of what i can little by little. And I'm going to try that marvel mystery oil trick! I just want to hear the thing run already!

Mike,
Is there a post or thread on this site that shows someone doing the m30b35? I don't mind doing it my self i just want to make sure I know what I'm getting my self into, I hear you need to redo the fuel lines and fuel pump, etc..

HB Chris,
if I had 10k to spend on a motor swap, I would probably to a s54 swap on my e30 first, but I totally understand the demand for those motors now on these early model BMW's, especially a 5 Speed swap, I hear that like finding gold if i wanted to source one out haha.

 

[Mike Goble]

Fernando -
I did mine back in early 2011 and made a few posts with questions about problems I was having. Here's a link to some of my posts: http://www.e9coupe.com/forum/search/21873/?page=5
Basically, it's a 1988 motor that I found in Sacto for $100 ( half price day at P-n-P), put my Weber carbs on it, adapted the cam to drive the stock distributor with a BMW cam adapter nut, bolted it in the car and it fired right up. I had to plug a hole in the oil filter cavity to get good oil pressure, and it's been running great since then.

 

[naccer]

I do not know if that head is compatible. It likely is. These things are like Legos it's pretty neat. You want trip webers or a motronic with a Dinan chip or whatever you can do it.

For mystery oil I had a Bentley T2 locked up and it took 3 treatments but eventually we could turn it over. Drained it out oil in it plugs in it and it started.

Please let us know how it goes. It's a 10 minute job to pull the plugs. Check the gaps while they're out. Mine were all way off when I got my 3.0. .28 works for my setup.

 

[afeustel]

Keep the M30 but go to a B34 or B35 motor.

If you are mechanically inclined this is not difficult to do. I had to rebuild my M30B34 and the machine work and head rebuild was $2.5k. Add the cost of parts (pistons about $900 and all the other bits) and you can have a fresh motor for about $3.5k. If you do all the assembly yourself you could probably do a swap for under $4k when it is all said and done. 5 speeds are going from $500-1000 now. A/C is not impossible, you just need the in-car console parts and evaporator, and a mount for the compressor on the block. Condenser, compressor, and dryer can all be aftermarket and look/work great. Compressors are about $250 new.

Megasquirt fuel injection system will add about $1.5-2k depending on how you source your parts and assuming you do all the work for the install.

If you find a motor that is used but decent (usually around $300-500 from a yard) then it really is just a swap in and if you use the intake from your old motor with some larger carbs it should be fairly straightforward. As Naccer mentioned, be careful with the head/block match-up if you do not purchase a complete motor. I think a B35 head has a smaller combustion chamber and only works with the flat pistons. If you have a M30B34 block/pistons, it may have dome or piano pistons that can create some pretty high compression ratios and possibly clearance issues with a B35 head.