Engine swaps/sensors

F

frogisland

Well-Known Member
Messages
296
Reaction score
99
Location
Cheshire, UK
Initially i am putting a tuned m90 in my car, but eventually building an engine with a combination of b34 block/b35 head/m90 crank and dissy cover. As such i collected a couple of engines at the weekend including a m30b34 engine and also another dogleg box.

Although of no consequence for my build, i am curious...the e28 bellhousing i have has the two holes for sensors. Are these crank position and speed sensor (latter in lieu of no mechanical pickup)? If someone was doing a m30 swap (wih an associated 5 speed) would they need these two inputs for the ecu on the bellhousing or can they be picked up elsewhere? I guess the bellhousing with sensor mounts would be the best way forward (as opposed to the e12 bellhousing that does not have the mounts).

I vaguely remember b34's having a crank position sensor at the front of the engine though like the m20's?

Hopefully someone out there understands my ramblings!

JP
 
JP - see this thread link for what is at the bell housing. Note, you would need the correct flywheel with the pins for the position sensor to read. The after market EFI systems could probably work with either the bell housing sensor position or the front 60-2 toothed wheel. I just use a single VR sensor on the front that measures both crank position and rpm. Not sure if I could measure them separately.

http://www.e9coupe.com/forum/showthread.php?t=10943
 
I think this will help...

b34 with a b35 head is only suitable for a 15 psi or larger forced induction engine.
 

Attachments

  • comp.jpg
    comp.jpg
    74.5 KB · Views: 108
sfdon:

Is an AMC head a b35 head? I have one on a m30 Euro 3.5litre and was told by the PO that the CR was less than 9.0:1

Doug
 
Interim engine will be modified m90. Parts being collected for longer term race engine; b34 block/b35 head will be having alot of internal work done by others. b34 block has same mounting points as m90, will be bored to 94mm and use m90 crank, b35 head better starting point for significant rework/wild cam, will use m90 front dissy plate.

This is the configuration alot of the 12v 3.5 European race cars use.

Re sensors, for those swapping an entire b34 or b35 engine, box and management, then i guess it is prudent to obtain an entire assembly and loom and ensure one gets the bellhousing with sensor mounts. Would be very easy to buy an engine/loom separately from a 5 speed/bellhousing not realising the difference in the latter with respect to sensors (and not forgetting the flywheel). Athough not applicable to my intentions, i learnt this at the weekend after noting the differences in boxes/bellhousings i have.

JP
 
Last edited:
Spanish heads are Standard- they fit everything except the b35 engine.
Real difference is pistons-dished, flat, domed or raised
or piano top.
 
The sensor at the front on the early jet and Motronic engines is only for the diagnostic plug.
 
sfdon - yes, I am running wasted spark. The distributor is gathering dust on the shelf.
 
Can you meet me in Seattle between the 16th and 21st?
I have a 745i turbo wasted spark and a Ferrari job there.
Would like to pick your brain on wasted spark and cs tach issues.
Thanks!
 
Yes, I should be around that time frame. I am located just across the lake. PM me with your info / schedule when the time is closer.
 
You must log in or register to reply here.
Back
Top