I'm going down the M42 road.

[kura2]

Hi Guys,Blown my m20b20 head gasket a few days back and decided to do M42 swap but are a bit wary cause most info found online is on M40 to M42 conversion. Here are some of my questions on the swap. Please comment/add/shoot:1. Read somewhere mine is getrag 240 so can use back with m42?2. Can use back m20 mounts cause its fairly new? Or need to find m40 mounts?3. Can use back m20 radiator? fan clutch can fit?4. Can use back m20 starter? or use the one that came with m42?5. Any recommended workshop around ampang/pandan?6. Any recommended exhaust shop for modifying the exhaust manifold? No budget for custom header yet.As for engine management I'll be using megasquirt with COP from toyota camry.

 

[fabianyee]

- M20 Getrag gearbox has slightly different bolt pattern to the M40 G240 gearbox... the 2 bigger bolts will not aligned to the engine block..
- longshaft length is different...
- M20 engine mounts can be used.
- u can use M20 starter if u use the M20 flywheel... the pinion teeth were supposed to be different...

A lot of things are different... Though can be done but needs more time compared to M40 to M42 swap...

If u want header, I have header for M42... hehe...

 

[kura2]

So gearbox kenot use ke? Or can make do without those two bolt. Your old header still got ke?

 

[mizhan]

kura2.. put in a M20B25 instead, you'll have lesser worries moving from M20B20.

 

[chili e30]

kura2.. put in a M20B25 instead, you'll have lesser worries moving from M20B20.

agree with mizhan just put in m20b25 motronic is just plug & play...

 

[munk3ong]

kura2.. put in a M20B25 instead, you'll have lesser worries moving from M20B20.

Haha..dah offer him de internals from m20b23..plug n play..but mention fc n weight was de main concern..hence good luck bro n enjoy ur ride..cheers

 

[mizhan]

Haha..dah offer him de internals from m20b23..plug n play..but mention fc n weight was de main concern..hence good luck bro n enjoy ur ride..cheers

oh well.. one can't have everything one desires

 

[ICEMAN 68]

get an m50b25 ...

 

[fabianyee]

my old header is with jonniez in KK...
U can check with Berserkdroid whether he still has his old header...

the M20 gearbox still can be used with the M42 engine, similar to what the E34 guys running M20 gearbox with M50 engines. (M4x and M5x blocks have the same gearbox bolt holes)..
U need a M40 long shaft...
M20 Radiator can be used but the fan shroud not compatible... but u can consider running custom electric fan...

 

[kura2]

Thanks for the b25 suggestion. Couldn't agree more that b25 is the natural upgrade for my car if I'm using it for daily drive but I rempit with kapcai most of the time hehehe, car intended for genting sempah/kelawang/bukit tinggi/bukit putus road only.

 

[kura2]

my old header is with jonniez in KK...
U can check with Berserkdroid whether he still has his old header...

the M20 gearbox still can be used with the M42 engine, similar to what the E34 guys running M20 gearbox with M50 engines. (M4x and M5x blocks have the same gearbox bolt holes)..
U need a M40 long shaft...
M20 Radiator can be used but the fan shroud not compatible... but u can consider running custom electric fan...

Hmm, so I need to get M40 oil sump and long shaft only? M20 long shaft too long or too short? If too long can potong..

 

[kura2]

I manage to source E30 RHD M42 headers and mount arms from UK. He also have the complete intake manifold. Wonder if you guys know if E30 intake manifold is better than E36 DISA intake manifold.

 

[morpheus5039]

Thanks for the b25 suggestion. Couldn't agree more that b25 is the natural upgrade for my car if I'm using it for daily drive but I rempit with kapcai most of the time hehehe, car intended for genting sempah/kelawang/bukit tinggi/bukit putus road only.

Bro if you like to climb hills then M20B25 will be even a better choice since it has longer stroke = more torque down lower rpm. (Greater pleasure at acceleration)
For the weight difference between M20 and M42, are you sure you will fully utilize the handling advantage of lighter front end everytime you attack the hill corner? (I do not mean that I suspect your driving skill, I mean do you really take the car to the limit everytime you climb the hill?)

 

[kura2]

Bro if you like to climb hills then M20B25 will be even a better choice since it has longer stroke = more torque down lower rpm. (Greater pleasure at acceleration)
For the weight difference between M20 and M42, are you sure you will fully utilize the handling advantage of lighter front end everytime you attack the hill corner? (I do not mean that I suspect your driving skill, I mean do you really take the car to the limit everytime you climb the hill?)

The answer is yes but then i cruise most of the time, hati tak cukup kering hehehe. Right now it kinda nose dive at corner. Hopefully m42 will cure this.

 

[morpheus5039]

The answer is yes but then i cruise most of the time, hati tak cukup kering hehehe. Right now it kinda nose dive at corner. Hopefully m42 will cure this.

Bro, you mean understeer? I think it can be reduced(If not fully) by adding adjustable sway bar, I am not sure about available products for E30, but you can ask fabian.

Or adding counterweight at the back of the car?

 

[mizhan]

morpheus is right about the sway bars helping. get those by H&R or better yet Ireland Engineering - that ought to address understeer and excessive body roll.

 

[kura2]

hmmmm, not really understeer, maybe i don't like the way the weight transfer during braking upon corner entry or maybe not enuff skill to handle e30 yet, dunno la. Might be getting UR bars in the distant future but right now I'm good with my IE stage 3 springs.

 

[kura2]

Bumping my old thread, had lot of track fun since the swap. Below are my current/future so called cheapskate mod list:

Current:

Use back b20 gbox, clutch, flywheel
Change diff to 4.1
MS 1 board v2.2 (cheapest standalone i think)
AEM wideband
M52 coil packs
IE Stage 3 Springs

Future:
4 throttle upgrade(curi from 4age),
lsd(or just weld it?)
shorten current shocks (billy black)
ultra Racing goodies
dyno tune MS ecu