Hello M42 newbie is here

[e34biturbo]

Hey guys...

My nephew picked up a 1984 E30 318i from his job for nothing...
and asked me to help him build a nice 4cyl project car......

well I am tired of see ing the asian 4cyls making all the power
so i am going to ask for basics on the differences between the M42 and
the M44 motors powerwise and fiting into the E30.......and see if we can come up with a stunner of 4cyl power....

So any help and info on both motors will be of great assistance


http://memimage.cardomain.net/member_images/3/web/2403000-2403999/2403273_1_full.jpg
http://memimage.cardomain.net/member_images/3/web/2403000-2403999/2403273_3_full.jpg
http://memimage.cardomain.net/member_images/3/web/2403000-2403999/2403273_4_full.jpg

[nickmpower]

dis is gunna be insane!!!!!

the m44 has shitty internals. get an e36 m42, replace the crank with the m47 one, and get low comp pistions to fit the longer stroke crank.

[e34biturbo]

dis is gunna be insane!!!!!

the m44 has shitty internals. get an e36 m42, replace the crank with the m47 one, and get low comp pistions to fit the longer stroke crank.

ok

give me a heads up on the diferent motors...

M42 is what year
M44 " " "
M47 " " " "

what is the hp ratings on each one ...or where can i look for this info...:)

[thumper3ld]

The e36 m42 you would want to get up to 1995. After 95 they went obdII and I dont think you would want to mess around with that.

[e9nine]

Your Neph's car has an m10b18. It runs on Bosh K-Jet. This engine was used in e21 and early e30 318s. You can just google it for more accurate info.

Most of the cars on this site have the m42b18 which is found in the 1991 e30s.

The e36s also have a slightly different yet very similar m42b18 and then the m44b19

For help with the m10b18 your best site are e21 sites

The m10 block is more potent in boost form than our m42s. Simpler to get some big power out of in comparison to m42 and m44s.

For example...

http://i3.photobucket.com/albums/y83/lisaotis/dyno001.jpg

http://i3.photobucket.com/albums/y83/lisaotis/IMG_0451.jpg
You can contact that dude to see his m10 build specs on BFc under username: good & tight
(http://forums.bimmerforums.com/forum/member.php?u=51597)

[bmwman91]

M42 is 1990+ 318i/iC, 1991 318iS for the US.
M42.5 (it has knock sensors) is 1992-1995 318i/iS/iC
M44 is OBDII 1996+ 318 cars.

The M47 was a diesel version of the M4x family of motors. Europe had M40 and m43 as well which were single cam economy motors, wheras th M42 was the sport-model motor over there. The US got ONLY the M42...the Germans knew a BMW that got great mileage but didnt go super fast would never sell to Americans, but for your purpose the m42 is what you want anyway.

The M10 in yours CAN be built into a pretty crazy turbo monster with time and $$$. The M42 is significantly harder to go FI with.

Your goals. What sort of numbers are you looking for? It is highly unlikely that you will get an M42 to make bigger numbers than most newer Asian import cars. Now, it'd cost you the same amount on any car to build a bombproof, tasteful, reliable motor, but if you are just tired of getting beat by teenagers with cheap bolt-ons it can be hard to do without $$$. Unfortunately we lack the aftermarket support that the Asian cars have, although 85% of the stuff on the market for them is absolute garbage (so I guess we are lucky to not have an overabundance of aftermarket stuff!).

Nevertheless, it is hard to make an M42 put up better NUMBERS than many rice rockets. Quarter mile times are usually better for them too. The real difference is on the windy roads...unless it is an AWD STI, EVI VIII, or SRT Neon or something, it will not keep up there. Even then, 90% of the owners of the aforementioned cars are irresponsible, spoiled teenagers that think the Fast & Furious/Need for Speed are reality. Lol, sometimes they decide to get some real racing in and play Grand Turismo to hone their driving skills. My advice, don't race them because they will take you out as well when they lose control!

Ok, that was long, and a little off-topic. M42 vs M44...the M44 makes a LITTLE more power (like 4bhp), probably due to its using a MAF sensor. It uses finger-lifter vs. the M42's direct-actuated lifters. Cannot revv as high, but it has less friction than direct actuation. The E36 M42/44 has a variable-length intake system that hinders top-end power. The M44 has cast crank & rods, where the M42's are forged. Ask all the questions you want, I'll try to keep future replies shorter lol!

[e34biturbo]

The e36 m42 you would want to get up to 1995. After 95 they went obdII and I dont think you would want to mess around with that.

what is the power/trq out put and displacement ?

is it belt or chain driven...

[e34biturbo]

Your Neph's car has an m10b18. It runs on Bosh K-Jet. This engine was used in e21 and early e30 318s. You can just google it for more accurate info.

Most of the cars on this site have the m42b18 which is found in the 1991 e30s.

The e36s also have a slightly different yet very similar m42b18 and then the m44b19

For help with the m10b18 your best site are e21 sites

The m10 block is more potent in boost form than our m42s. Simpler to get some big power out of in comparison to m42 and m44s.

For example...

http://i3.photobucket.com/albums/y83/lisaotis/dyno001.jpg

http://i3.photobucket.com/albums/y83/lisaotis/IMG_0451.jpg
You can contact that dude to see his m10 build specs on BFc under username: good & tight
(http://forums.bimmerforums.com/forum/member.php?u=51597)


:eek: :eek: damn I just got a headache....I like that dyno graph.....that is some nice power.....so you are saying that the M10 is more boost friendly than it's sibling M42? with the twin cam and all?HMMMMMMMM

Ok now I know big sixes in and out....but the 4bangers.

Now as far as the M42 goes or M10 a complete standalone is in order...
so u think M10 better under boost than the M42 in that case?

[bmwman91]

Now as far as the M42 goes or M10 a complete standalone is in order...
so u think M10 better under boost than the M42 in that case?

Good. So many people want a turbo setup and fuel amnagement via a pressure regulator & injectors. Kudos for knowing the RIGHT way!

Yep, the M42 is just not very FI friendly. The M10...I have seen some monsters.

Factiods
The M10 is a sibling of the m30 'big six' and the S14 (M3) was based upon it as well. The M42 was a totally new design from scratch. It is closely related internally to the Euro S50, and was the base for the M5X and S5X engines.

[e9nine]

If you want to use an m42 - get a complete m42 car as a whole.
If you want to use an m10 - stay with what you got.

As you do more research you will notice the m10 to be easier to obtain parts for even if you want custom pistons etc. The m42 starts of with a 10:1 compression ratio.

Now it's not that the m42 is a bad option - it's pure preference as usual but seeing the monsters you have built and your experience I see you using an m10 to embarass people. If you choose to go the m42 route it would be awesome. It's all about the power your neph can handle and if he will prefer plastic bumpers over diving boards (the metal bumpers) by having power and looks of if he wants a full blown sleeper and how his deep his pockets are.

[e34biturbo]

:cool: Good. So many people want a turbo setup and fuel amnagement via a pressure regulator & injectors. Kudos for knowing the RIGHT way!

Yep, the M42 is just not very FI friendly. The M10...I have seen some monsters.

Factiods
The M10 is a sibling of the m30 'big six' and the S14 (M3) was based upon it as well. The M42 was a totally new design from scratch. It is closely related internally to the Euro S50, and was the base for the M5X and S5X engines.

I believe in doing it right the 1st time around.......so DTA standalone is a must on a motor that old..
so I will just advise to get a spare M10.....:cool:

[haledj]

I have owned both cars and if you want a strong reliable unmodified car than go m42 for sure.
However if you want a project, something that will fly in a straight line after some work, go with the m10. Another advantage of the m10 318 is its weight. You can get them down to 2100 pounds rather simply. the m10 really has a lot of potential, the 2002 with the m10 ( different head) reportedly produced 1500 hp in qualifying trim (exact number is up for debate but it is rediculous power regardless). Also the m10 is very solid and bullitproof even under boost. Some have reported blowing head gaskets under a lot of boost.
--doug

[nickmpower]

well the only problem with the m42 is its compression right? if custom pistons are bought, it doesnt seems like there would be a problem

[bmwman91]

The 10:1 compression is a big part of the difficulty, for sure. Pistons could fix this.

The thing I wonder is: the M42 can only be overbored to gain ~+150cc's max. Being that there is not much material between cylinder bores/thin water jackets, a really high boost motor could see some serious failure. I am not very knowledgeable about FI system building though, so this may just be my engineering background making me scared.

[e34biturbo]

If you want to use an m42 - get a complete m42 car as a whole.
If you want to use an m10 - stay with what you got.

As you do more research you will notice the m10 to be easier to obtain parts for even if you want custom pistons etc. The m42 starts of with a 10:1 compression ratio.

Now it's not that the m42 is a bad option - it's pure preference as usual but seeing the monsters you have built and your experience I see you using an m10 to embarass people. If you choose to go the m42 route it would be awesome. It's all about the power your neph can handle and if he will prefer plastic bumpers over diving boards (the metal bumpers) by having power and looks of if he wants a full blown sleeper and how his deep his pockets are.

I might just do one of each motor......
but the M10 is sounding like my dream....baby SOHC:D
well pockets are not an issue we will be doing most of the work 98% with pics as with all the others.......this will be my debut tuning the engine with the DTA all by myself no help....I feel the M42 will be able to make 500 to the wheels......the M10 similar......so let the games begin!!!!


Oh talk to me about the tranny variations.......

I got an E30 2.5l tranny and an E36 2.5l tranny.......

[e34biturbo]

The 10:1 compression is a big part of the difficulty, for sure. Pistons could fix this.

The thing I wonder is: the M42 can only be overbored to gain ~+150cc's max. Being that there is not much material between cylinder bores/thin water jackets, a really high boost motor could see some serious failure. I am not very knowledgeable about FI system building though, so this may just be my engineering background making me scared.


Hmmmmmmm Compressionwise I plan to go no lower than 9 0 1......so eliminate the dogginess of the 4banger....add some good internals and hold on tight....I would not over bore either motor....need that meat for the heat and friction...

I might just try a stock motor 1st to see what is what then when it blows rebuild it ..........

[thumper3ld]

Hmmmmmmm Compressionwise I plan to go no lower than 9 0 1......so eliminate the dogginess of the 4banger....add some good internals and hold on tight....I would not over bore either motor....need that meat for the heat and friction...

I might just try a stock motor 1st to see what is what then when it blows rebuild it ..........

I've heard you can run 6 or 7 lbs of boost on a stock m42 motor. I plan on trying the same thing and seeing what happens. But if you want to try first, then please, be my guest.

[e9nine]

I might just do one of each motor......
but the M10 is sounding like my dream....baby SOHC:D
well pockets are not an issue we will be doing most of the work 98% with pics as with all the others.......this will be my debut tuning the engine with the DTA all by myself no help....I feel the M42 will be able to make 500 to the wheels......the M10 similar......so let the games begin!!!!


Oh talk to me about the tranny variations.......

I got an E30 2.5l tranny and an E36 2.5l tranny.......

Do up an e30m42 turbo. We get no love. All talk no show with most boosted m42s in the USA.

Tranny failure hmm...Getrag 240 hasn't been pushed far by most. Check out this dude's page http://www.ticco.com/318tic_e.html and look under 2002 to see what he had done in the past with his m42 before going with an m20 :(.

He ended up with " About 250+ hp. Original 10,0:1 compression. (not safe!) 325 (3,73) differential." as his final numbers when I PM'd him ages ago about his set up.

His site isn't in full english and kinda hard to navigate but u can see what he did with the basics.

The Getrag 240 can be used for m/s50 conversions (but very few choose to say with it) so perhaps a getrag 260 can be mated to the block as well? Sadly you might have to do a lot of trial and error but the good thing is you already have the other trannies handy. It's just the mix of the flywheels and pressure plate along with throwout/pilot bearings and slave cylinders that will get interesting. I don't think driveshafts *might* not be too much of an issue. If you do stick with the getrag 240 you can use the m20b25 flywheel with modification to the starter pinion gear and use a 323i pilot bearing.

When you get your project started others will obvioulsy chime in to help out as much as possible. I don't do turbo stuff - I just appreciate the hard work and try help as much as I can with moral support :D

[bmwman91]

Tranny-wise, zerofrez on here works in a shop and says that and tranny from an S/M5X family motor bolts right on, since the M42 is essentially one of them missing 2 cylinders.

My cylinder-wall concern was not due to boring it out, it was that there is nto much meat in there to begin with. Now, I am not at ALL saying to not try it. The though of one more already-rare M42 going south does nto appeal to me, but my curiosity is even stronger! Dooooo iiiiit!

[Febi Guibo]

the M42 can only be overbored to gain ~+150cc's max.

for N/A applications this isn't quite true... just an fyi.

[bmwman91]

Interesting...what IS the max displacement increase an M42 can reliably undergo?

[e34biturbo]

I've heard you can run 6 or 7 lbs of boost on a stock m42 motor. I plan on trying the same thing and seeing what happens. But if you want to try first, then please, be my guest.

I plan to blow them both
:D

[e34biturbo]

Tranny-wise, zerofrez on here works in a shop and says that and tranny from an S/M5X family motor bolts right on, since the M42 is essentially one of them missing 2 cylinders.

My cylinder-wall concern was not due to boring it out, it was that there is nto much meat in there to begin with. Now, I am not at ALL saying to not try it. The though of one more already-rare M42 going south does nto appeal to me, but my curiosity is even stronger! Dooooo iiiiit!

so the M10 should in theory be able to use a 260/265 box

[Febi Guibo]

Interesting...what IS the max displacement increase an M42 can reliably undergo?

I'm at a little over 2100cc...

[bmwman91]

I'm at a little over 2100cc...

2100...that is stoked AND bored right? Any idea what the max displacement with just an overbore is?

Overbore it and turbo it, if you are gonna blow it up anyway!

[Febi Guibo]

my non-scientific opinion is that for f/I spplications, you could take it out to S50 size pistons... around 86.5 mm or so....