Getting the most from the M40B18

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pac1982
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Post Thu Jul 11, 2013 11:24 pm

Dont worry not your usual post on how can i get 200bhp by spending 50p on my M40 lump.

I know the M40 is quite a weedy engine but i have decided to keep my car standard seeing as its one of the Neon design limited editions.

My current engine runs fine but as i'm driving it at the moment i plan on buying another M40 lump to fully rebuild.

without going silly and bolting turbos, super chargers etc on is it worth doing anything to get just a wee bit more from an M40, or should i just do a full re fresh and leave it at that?
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Billwill
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Post Fri Jul 12, 2013 8:48 am

Turbo is the only thing that will give you more power.

Dropping an M42 engine in would be the best solution but not if you want to keep standard. :wink:
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cal1993
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Post Fri Jul 12, 2013 4:22 pm

CLEARLY put stripes on it 10bhp per strip mate.... :mad:
suedenim
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Post Fri Jul 12, 2013 5:13 pm

Does a lightened M20 flywheel do anything to liven them up, anyone done it?
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Grrrmachine
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Post Fri Jul 12, 2013 5:31 pm

There's fuck-all you can do to an M40 other than make sure the camshaft hasn't turned into a Toblerone. Fully rebuilding one seems massively pointless considering its such an inferior engine.
DanThe
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Post Fri Jul 12, 2013 7:26 pm

To get the most from an M40 you take it to the scrap metal merchants and drop it on the weigh bridge
Morat
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Post Fri Jul 12, 2013 10:55 pm

It's not a _bad_ engine. It's pretty sprightly and reliable if the cam is in good nick - but it's just not worth tuning.
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Post Fri Jul 12, 2013 11:04 pm

mine done 125 mph :D
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suedenim
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Post Sat Jul 13, 2013 12:00 am

Morat wrote:It's not a _bad_ engine. It's pretty sprightly and reliable if the cam is in good nick - but it's just not worth tuning.
It is what it is, never going to set the world on fire but it can withstand abuse, free revving and can be quite rewarding if you keep it on cam.
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pac1982
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Post Sat Jul 13, 2013 12:18 am

when i say a want a bit more from the old donk i'm really just trying to make it feel a bit more alive it feels such a lazy engine.

I would love a better lump and prehaps i'm looking in to this limited edition thing to much although I have seen really nice original ones with average miles sell for strong money
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suedenim
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Post Sat Jul 13, 2013 12:29 am

Why not bite the bullet and fit an M42, you won't have to butcher it to make it fit so it's always reversible.
I don't personally understand being burdened with a mediocre driving experience when you could easily be enjoying it more. If anything, you'll preserve the original donk.
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ajay
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Post Sat Jul 13, 2013 9:59 am

Fitting an M42 IS lump will not affect the value of your car, i have done the swop from M40 to M42 in our cab, it still looks original the insurance ( norwich union) have been informed and accepted it with no extra cost on the policy ( due to same cc). The car now flies and can still be thurther improved, ie m20 flywheel, bbtb, ecu upgrade, cams. Its now a totally different car to drive, i have another E30 with S54 conversion, but still enjoy going for a blast in (the misses M42 cab) they are great engines and a wholely satisfying conversion, i say as above forget about improving your M40 if you want a real improvement fit an M42!
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jonesy318
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Post Sat Jul 13, 2013 4:23 pm

im in the process of fitting m42 conversion in mine, the old m40 cam was totally shot and as everyone says its a simple swap and far better engine, don't see much point in wasting money on the old m40 to be honest
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Post Sat Jul 13, 2013 4:36 pm

All BMW's should have proper,six cylinder engines.

I have a 2.7 M20 in my neon green cabbie.All totally reversable should I ever sell to an OEM buftie type.
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