M42 into M40

[ianclapham]

i have just bought a 1989 e30 with a m40 lump for road rallying, if i can find a m42 engine what kind of a job is it to put into my standard m40 car.

thanks

ian clapham

[320ise]

i`d like to know this too just for future reference

[GrindCulture]

Easy as pie to do. If you can find an engine with all needed ancillaries (mounts, loom, exhaust system, ECU etc.), gear box and proshaft, it literally just swaps in where the M40 went. The only extra little bit is welding the coilpack bracket onto the o/s wing. You can avoid doing this by doing a coil-on-plug conversion using a home-made bracket and M54 coils.

The M40-M42 swap was my first major mechanical undertaking, with very little experience in anything else bar basic servicing. That's how easy it is

[320ise]

would e36 i.s items fit?

[robbo86]

yes but you would need all original e30 IS mountings.....

I have just bought an IS engine for the conversion and will be tackling it if I can find a decent sized garage, otherwise wating till the weather improves and doing it in my mates garden.

[robbo86]

http://www.e30zone.net/modules.php?name ... c&t=112713

check this thread, I have asked jus about every anally retentive question known to man on this conversion in that thread. Should answer most, if not all your questions, there was an IS engine for sale about the time I bought mine, might still be available.

[320ise]

will the e36 i.s gear box fit? allso why do you have to change the prop thought 318i/is used the same? would e36 prop be ok to use?

[robbo86]

I dont see why not although someone like Brianmoore is the guy to ask for sure, again may be a case of needing e30 mountings

[GrindCulture]

M40 propshaft does not work if you're using the M42 gearbox. I found this out just as I thought I'd finished, then realised that the centre bearing was wankered...

[Baz666]

speak to bob_s he has an iS engine for sale.

[cass1_5503]

would e36 i.s items fit?

for this you would need to change the sump and timing covers i think not sure if the gearing of the e36 box is the same as the e30 one, if it was me i would wait for e30 items to pop up they do every now and then.

[monkey]

will the e36 i.s gear box fit? allso why do you have to change the prop thought 318i/is used the same? would e36 prop be ok to use?

the e36 318is gear box has a straight through 5th gear and the e30 box has a straight thought 4th gear and an overdrive 5th or a geared up 5th . if you fitted an e36 box it would be reving high in 5th like you where driving it 4th gear .

[GrindCulture]

The only way you would compensate for the E36 box would be to fit a different ratio diff, but even this it would be hard to get it right.

[monkey]

poss a 3.64 would do it may be even higher

[robbo86]

the e36 318is gear box has a straight through 5th gear and the e30 box has a straight thought 4th gear and an overdrive 5th or a geared up 5th . if you fitted an e36 box it would be reving high in 5th like you where driving it 4th gear .

Sorry I am not far off fitting an IS engine with an IS box. What do you mean by this! i know I porobably sound pretty thick but..... well...... I am!

[monkey]

5th gear is the same as 4th on an e30 box = e36 gearbox in to an e30 means the engine will be reving it nuts off all the time as the gear ratios will be too low

[robbo86]

5th gear is the same as 4th on an e30 box = e36 gearbox in to an e30 means the engine will be reving it nuts off all the time as the gear ratios will be too low

Had to read that a couple of times to figure out what you mant, but I get you now.