Someone put me out of my misery - e46 M3 engine swap.

Post Thu Feb 05, 2009 9:02 pm

OK, those 'how hard can it be' gremlins are perched firmly on my shoulder right now.

There is a real dogs dinner of an E46 M3 up on the bay, ripe for pillaging of all its expensive bits - twice written off M3 - item 280310488083

Has anyone done this swap before? I know that all the ECUs, keys, dash, probably even the rear seat are coded to the car, but still ......

Thoughts?

Martin.

Post Thu Feb 05, 2009 9:06 pm

I've seen/heard of at least 1 S54 E30. It will be stupidly expencive, possibly even cost more than buying an E46 M3 outright.

Post Thu Feb 05, 2009 9:08 pm

A brave undertaking I'd say

Have you got the facilities to do the swap and space to frag the M3?

Post Thu Feb 05, 2009 9:27 pm

Here is a link to a build thread for an s54 e30 -

http://forum.e46fanatics.com/showthread ... 200&page=1

Now I've read the whole of this 50 odd page monster and can summarize as follows -

The guy who built it is an MIT graduate and has a sickening understanding of electronics.
He made it difficult for himself by using the SMG flappy paddle gearbox, which requires the DSC traction control, which requires retrofitting ABS with an e36/z3 hub and sensor set up.
Basically the guy has taken the full electrical system from the e46, ECUs, loom and everything, and built it into an e30 shell.
he also has a friendly BMW dealer onside to help him get all the bits to talk to each other.
The thread tails off with one of the last updates being that the car would constantly get a DSC fault code showing up which puts into a limp mode stopping it from revving past 3000rpm.

You can't just drop the engine and ecu into an e30 and have it just work, it needs signals from all over the car. I'd read the thread before bidding on that smashed up e46.

So to answer the question 'how hard can it be?' Pretty f**king hard!

Best to just go with the tried and tested s50 route.

HTH

Post Thu Feb 05, 2009 9:43 pm

was looking this up today (mainly as i have a spare motec m4)

it seems the best way to do it would be bin the ecu and use an aftermarket ecu setup that can run the vanos - definately not those for the light of wallet or faint of patience

IMO the best option looking at current prices - buying a 2-4k e36 m3 and fragging it. harsh for a perfectly running car (which is where the idea falls down) but the most cost effective i think (i can't believe m3 engines are on ebay for 1900 quid at least - by the market values of most cars ive seen thats 60% of the cost in the engine alone - madess)

Post Thu Feb 05, 2009 9:47 pm

What could be done to get the S50 to 350bhp? Surely even that would be cheaper and easier than the S54 madness!

Post Fri Feb 06, 2009 12:15 pm

mr_dink wrote:Here is a link to a build thread for an s54 e30 -

http://forum.e46fanatics.com/showthread ... 200&page=1

So to answer the question 'how hard can it be?' Pretty f**king hard!

Best to just go with the tried and tested s50 route.

HTH

What a great thread, thanks for posting. So even with an MIT electronics whizz, a talented engineer and a friendly dealer, it still encountered many, many problems

Now part of me is asking myself if I have that dedication, to spend the rest of my life diagnosing and fixing rather than enjoying it.

Another part is saying it has to be easier with a whole donor car, and a manual box, and the fact that at least a couple of people have done it before.

I am sure I could spend far less money going forced induction on my M30, and get near that power. Not sure why really, but that just sounds too easy somehow, I think the fact that it is a damn hard challenge appeals more than the end result.

Off to lie down in my padded cell now ....

Martin.

Post Fri Feb 06, 2009 2:24 pm

Hi,

MJJ_ZX6RR- Just some information for when your
not busy lying down in your padded cell.

For the standalone ECU[Motec]/looms/sensors etc, and then the dyno mapping,
nothing else, just those components, for a Track based car with the
Vanos deleted has just topped 8K +.

Seeing as E46 M3's can be had for circa 8-9K it even
makes S50/S52 conversions seem pointless in the current climate.

And if you want to go stand alone and retain the Vanos,
figure around 2-3k to map it correctly, and you still
only just about equall the factory specs.

Mapping an Engine is one thing, mapping constanlty moving
cam lift and duration and overlap, is a whole new ball game.

Regards,

The Gorilla.

Post Sun Feb 08, 2009 7:09 pm

I've been involved in a couple of s54 projects and its not as bad as you may think, although not in e30 the principles are the same.

Basically dump the standard management and vanos units. Use fixed pulleys, mecanical throttle linkage kit and aftermarket engine management. VAC sell all the bits you need. Cost of around 4k.

Both engines running on kms management and both made around 353bhp and 278lb/ft.

Post Sun Feb 08, 2009 8:32 pm

Dont you just love the cams

Post Mon Feb 09, 2009 12:33 pm

Jesus! I just spent all night and most of the morning reading that E30 S54 conversion thread, he must have really wanted SMG thats all I can say! One very clever fella.

Post Wed Feb 11, 2009 9:39 am

Technically there're no big problems with the swap, of course lots of things need to be sorted out but nothing major.
Electronics are The Problem, but as mentioned before, aftermarket ECU which can handle vanos is the thing to go with.

It won't be cheap swap but if you've the money - go for it!