M40B18 manual tranny swap

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Racer75
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Post Mon Nov 11, 2013 1:20 pm

Hi all, back again for more advice 8)

I'm interested in swapping the auto trans to a manual to make the pokey M40 a bit more exciting. There are a lot of great write ups online from people who have done the swap, but all there cars are LHD (not to mention M20s). Is there anything different between a LHD and a RHD or engines that I may have to look into further or is the swap or less the same?

Thanks in advance
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Brianmoooore
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Post Mon Nov 11, 2013 1:33 pm

First rule if you own an E30 is don't look anywhere for info., other than the zone! I can assure you there are very few, if any, LHD M40 conversions on here.
The M20 swap guides should be applicable to M40 conversions as far as I can see, apart from somedifferent specific parts, of course.
A M20 flywheel and M20B20 clutch assembly are a worthwhile mod. if you are sourcing individual parts from different sources. Need the M20 starter motor as well.
daimlerman
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Post Mon Nov 11, 2013 1:52 pm

LHD E30 uses the same fluid thingy for both brake and clutch,proper side drive requires a clutch fluid thingy adding to the o/s front( :D )suspension turret.The correct bracket will be available to order from your dealer,or you can fabricate something suitable yourself.

Pedal boxes are vastly different between LHD and proper side drive,assuming we are talking a proper side drive car the easy option is to bolt up the manual type pedal box.

Be aware that auto's have a cunningly arranged wiring loom add on that prevents you starting the thing in D or R,this needs to be removed,trace the start signal wire,black/yellow,from the ign switch to the area behind the glovebox,there you should find that it is split with a pair of black wires wandering off in a sub-loom.Remove the black wires and as much of the sub-loom as is possible...it disappears beneath the carpet to re-appear at the back of the gear selector...re-join the two black/yellow wires.At the gear selector end,you only need the plug that connects to the reverse light loom that should come with your manual 'box from the reverse light switch on it's r/h side.

The 'proper' way to remove this sub-loom requires the carpet to come out,this also makes the pedal box swap a touch easier,but just hacking the wiring away at each end will do the job!
Grrrmachine
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Post Mon Nov 11, 2013 2:52 pm

Second time today I've posted this...

http://www.e30zone.net/e30zonewiki/inde ... _To_Manual
Racer75
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Posts: 60
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Location: Motherwell, Scotland

Post Mon Nov 11, 2013 4:27 pm

Thanks guys for the advice. Much appreciated :D