M40 to M42 or IS?

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RRRR
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Sat Sep 13, 2008 4:06 pm

Toying with the idea of swapping my M40 to either:

1) M42 from a e36 318i
2) the e30 318is engine

which will give me more power?

Not considering the 2litre or 2.5litre engines.

TIA
DHFiS
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Sat Sep 13, 2008 4:12 pm

GrindCulture
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Sat Sep 13, 2008 5:49 pm

E30 318is motor is an M42, and as far as I'm aware they produce exactly the same figures.
Not in E30s any more :(
Alex
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Sat Sep 13, 2008 10:12 pm

RRRR wrote:Toying with the idea of swapping my M40 to either:

1) M42 from a e36 318i
2) the e30 318is engine

which will give me more power?

Not considering the 2litre or 2.5litre engines.

TIA
both the same, e36 m42 is what is fitted into e30 IS

you could go for the later e36 IS with the 1.9 m44 engine but iirc most people prefer the 1.8 m42's better

the early e36 318i had an m40 and later ones m43?
GrindCulture
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Sat Sep 13, 2008 11:57 pm

I've never driven a car with an M44 myself but people tend to say they're not a revvy as M42s, and only have an extra 4bhp, plus the crank is cast with only 4 counter weights where as the M42 has a forged crank with 8. E36 motors will need the E30 inlet manifold (and probably a few other little bits) to run in an E30.
Not in E30s any more :(
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RRRR
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Sun Sep 14, 2008 10:56 am

DHFis, GrindCulture & Alex

Thks for your inputs :D

Guess its M42 then and easier for a swap since I can keep the most of the M40 parts.

Cheers guys!
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R0yalratch
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Sun Sep 14, 2008 11:02 am

M44 has a fair but more torque and will be available in much lower mileages as you can get them from Z3's and E36 Compacts.

But the M42 is a much easier swap.
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RRRR
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Sun Sep 14, 2008 4:47 pm

R0yalratch wrote:M44 has a fair but more torque and will be available in much lower mileages as you can get them from Z3's and E36 Compacts.

But the M42 is a much easier swap.
pardon my ignorance, but the m44 is also a 4 pot?

TIA
Alex
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Sun Sep 14, 2008 4:48 pm

pardon my ignorance, but the m44 is also a 4 pot?
yep very similar to m42
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RRRR
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Mon Sep 15, 2008 2:07 am

Alex wrote:
pardon my ignorance, but the m44 is also a 4 pot?
yep very similar to m42
Thanks Alex.

M42 it is then. :D
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Brianmoooore
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Mon Sep 15, 2008 9:40 am

The only practical way to fit an E36 M42 into an E30, is if you have a complete scrap E30 iS M42 engine to source parts from. Most of the parts bolted on to the basic block and head, etc., will have to be changed.
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RRRR
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Mon Sep 15, 2008 11:04 am

Brianmoooore wrote:The only practical way to fit an E36 M42 into an E30, is if you have a complete scrap E30 iS M42 engine to source parts from. Most of the parts bolted on to the basic block and head, etc., will have to be changed.
rite, that might presents a bit of a problem coz its hard to find a e30IS half cut.

maybe i shd go for the 1.8L M40 - that would be a relatively simple affaire with most of the existing bits still reusable rite?

sorry for being indecisive - lack of knowledge :o:
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Mon Sep 15, 2008 11:06 am

just slot an e30 M42 in there.. Job jobbed :)
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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GrindCulture
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Mon Sep 15, 2008 5:07 pm

E30 M42s are easy enough to come by for reasonable prices, they seem to be broken for spares more and more as tinworm sets in.
Not in E30s any more :(
ric325i
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Mon Sep 15, 2008 5:17 pm

Yeah get the e30 318iS motor in there! 8) can get them for pretty good money and will be ok on the juice too.
if you keep it out the revs
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robbo86
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Thu Oct 30, 2008 11:18 pm

just bought a complete swap for 250

might do a step by step photoguide when i tackle it
GrindCulture
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Thu Oct 30, 2008 11:19 pm

Do it, I wish I did when I did mine but I got carried away.
Not in E30s any more :(
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Thu Oct 30, 2008 11:29 pm

no worries, will need pictures of the m40 lump when its out to sell it, certainly isnt much on the wiki about it
GrindCulture
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Thu Oct 30, 2008 11:47 pm

It's so unbelievably simple it doesn't really warrant documenting, but it would be a good thing to have if people are unsure if they can do it or not.
Not in E30s any more :(
robbo86
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Fri Oct 31, 2008 12:04 am

GrindCulture wrote:It's so unbelievably simple it doesn't really warrant documenting, but it would be a good thing to have if people are unsure if they can do it or not.
You mean me???

More than likely is, but mine is further confused by the exhasut issue and the fact I am going from auto to manual (clutch master cylinder, pedal box etc)

Guess I better also look into renting an engine crane aswell
GrindCulture
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Fri Oct 31, 2008 12:08 am

robbo86 wrote:
GrindCulture wrote:It's so unbelievably simple it doesn't really warrant documenting, but it would be a good thing to have if people are unsure if they can do it or not.
You mean me???
No, just generally. If people have never done an engine swap before (I hadn't before I tackled mine) it would be a good thing to have as a reference point, or just something to show people it's not as daunting as it might sound.
Not in E30s any more :(
robbo86
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Fri Oct 31, 2008 12:52 pm

No, I meant me really to be honest. It seems pretty daunting but my dad WILL help me (not sure he knows that yet) as he has done it before. He had a 3l granada engine in his ford corsair with a straight through exhaust back when he was my age so its not alien to him. It just seems far more daunting then I reckon it will be.
GrindCulture
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Fri Oct 31, 2008 7:48 pm

Best advice would be take your time, I took about 2 days going over everything methodically when taking the M40 out, making sure everything was disconnected, where it should have been, getting all the ancillaries out and making sure I knew where they were all connected. If you're not sure take pictures and label bits. After I'd done the first step, the M42 was out from one car and into the other within a day, by lunchtime the next day it was running (most of that morning was spent pissing about with the propshafts.) The M42 slots in exactly the same way as the M40, you just need to weld the coilpack bracket to the inner wing. If you need any pointers or get stuck at any point let me know and I'll do my best to point you in the right direction.
Not in E30s any more :(
robbo86
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Mon Nov 03, 2008 2:47 pm

The M42 slots in exactly the same way as the M40, you just need to weld the coilpack bracket to the inner wing
Time to borrow a welder then....

I might well have to take you up on that offer
GrindCulture
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Mon Nov 03, 2008 6:54 pm

You could probably drill some holes in the inner wing and bolt it down. Make sure you rustproof it afterwards though.
Not in E30s any more :(
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Brianmoooore
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Mon Nov 03, 2008 10:55 pm

GrindCulture wrote:you just need to weld the coilpack bracket to the inner wing.
Or convert to individual coilpacks.
robbo86
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Mon Nov 03, 2008 11:07 pm

Or convert to individual coilpacks
Where do these come from them Brian? I would assume they would still need to be attached somewhere so how do I go about attaching them?
GrindCulture
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Mon Nov 03, 2008 11:10 pm

You'll need 4 M54 coilpacks. You also need to make up a bracket to hold them in place. They sit on top of the spark plugs, removing the need for HT leads. You'll need to modify the loom accordingly too. Look in breakers yards for E46 6 pots and get pillaging.
Not in E30s any more :(
robbo86
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Mon Nov 03, 2008 11:26 pm

GrindCulture wrote:You'll need 4 M54 coilpacks. You also need to make up a bracket to hold them in place. They sit on top of the spark plugs, removing the need for HT leads. You'll need to modify the loom accordingly too. Look in breakers yards for E46 6 pots and get pillaging.
Worthwhile mods do you reckon.... modifying the loom though, sounds scary, I am fairly handy with a spanner but no mechanic, but when it comes to the dark art of auto electricals I want to run away and hide under a pile of coats till it goes away. Whence why I bought a sport mirror 6 months ago and havent fitted it. I dont have the advantage of having a check control panel to remove, making fitting even harder.
GrindCulture
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Mon Nov 03, 2008 11:29 pm

Very worthwhile mod, something on my endless to do list. Stronger spark, better combustion, much more efficient. To be honest I don't know whats required as far as modding the loom goes, it's nothing major I guess, just re-routing and tidying up in order for it to fit.
Not in E30s any more :(
robbo86
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Mon Nov 03, 2008 11:37 pm

Hmmmm probably worth giving the BMW breakers at charing a tinkle then!!! See what they go for.

Brian (or Brain seeing as you always have an answer for peoples technical questions), you any idea what is involved in modifying the loom, seeing as you suggested it an all?
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Brianmoooore
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Tue Nov 04, 2008 8:53 am

The standard iS coil pack is four seperate coils built into one housing, with four seperate connectors, so it's just a mater of extending/rearranging the loom so that these four connectors reach the coil packs. The iS connectors are similar to the M54 ones, but I don't know if they are identical.
robbo86
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Tue Nov 04, 2008 12:41 pm

Well seems like a plan. I will investigate further and possible do a write up when I do it, or has someone beat me to it do we know?
GrindCulture
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Tue Nov 04, 2008 5:44 pm

Brianmoooore wrote:The standard iS coil pack is four seperate coils built into one housing, with four seperate connectors, so it's just a mater of extending/rearranging the loom so that these four connectors reach the coil packs. The iS connectors are similar to the M54 ones, but I don't know if they are identical.
As fas as I'm aware they are, at least I've not read anything saying that the connectors need to be swapped in order to run the M54 items.
Not in E30s any more :(
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Tue Nov 04, 2008 5:50 pm

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M42 with coil on plug conversion (In a 2002 I think) just so you know :wink:
Not in E30s any more :(
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