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DISCUSSION => Engine + Driveline => Topic started by: 2002maniac on February 22, 2007, 07:56:28 PM

Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on February 22, 2007, 07:56:28 PM
i didnt really feel like taking my starter apart.  Why not just swap the toothed rings?  Not that hard actually!

(http://img.photobucket.com/albums/v485/2002maniac/IMG_0618.jpg)
Title: to skin a cat (m20 flywheel swap)
Post by: asubimmer on February 22, 2007, 08:16:29 PM
will the m42 ring fit the m20 flyheel?
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on February 22, 2007, 08:29:50 PM
looks like it.  I ran out of acetylene before I could get the ring off the m20 flywheel.  I'll have to get the bottle filled saturday.
Title: to skin a cat (m20 flywheel swap)
Post by: D. Clay on February 22, 2007, 10:08:55 PM
Tha sum in ja noo uh tee!
Title: to skin a cat (m20 flywheel swap)
Post by: mcfir7 on February 23, 2007, 06:52:27 AM
could it fit?nvr taught of that..u r smart ass dude
Title: to skin a cat (m20 flywheel swap)
Post by: dude8383 on February 23, 2007, 12:05:45 PM
i believe this is what MM do...
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on February 23, 2007, 12:13:21 PM
Quote from: dude8383;20041
i believe this is what MM do...


I guess great minds think alike :p
Title: to skin a cat (m20 flywheel swap)
Post by: D. Clay on February 28, 2007, 02:59:39 PM
Any update?
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on February 28, 2007, 11:25:03 PM
Oh yeah, it worked.
Title: to skin a cat (m20 flywheel swap)
Post by: asubimmer on February 28, 2007, 11:43:14 PM
awsome!
Title: to skin a cat (m20 flywheel swap)
Post by: BrandC on March 01, 2007, 12:04:44 AM
aaawesome
Title: to skin a cat (m20 flywheel swap)
Post by: dude8383 on March 01, 2007, 09:33:02 AM
shit thats pretty cool.

exactly how did you do it, an air chisel of some sort?
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on March 01, 2007, 04:38:41 PM
Quote from: dude8383;20356
shit thats pretty cool.

exactly how did you do it, an air chisel of some sort?


I just heated up the gear with the torch and beat it off with a hammer and chisel.
Title: to skin a cat (m20 flywheel swap)
Post by: dude8383 on March 01, 2007, 05:10:28 PM
Quote from: 2002maniac;20367
I just heated up the gear with the torch and beat it off with a hammer and chisel.


and vice versa right?
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on March 01, 2007, 07:42:54 PM
Yup.

I also discovered that if you have the flywheel lightened on the engine side, you dont need to space out the M20 flywheel as described in a few of the writeups.  

So basically:

 Have flywheel lightened
 Swap gears
 Use the 323 TOB and M20 clutch set

I'll post some more pics after I finish lightening the flywheel.

Here's a sketch showing why you need to space out the flywheel unless you have it lightened.  The engine side of the flywheel is to the left.  The M42 (did I write M44? oops!) flywheel is flat but the M20 one it is recessed.  Removing .230" would essentially make it flush like the M42 part.  Over .350" can be removed and will save quite a bit of weight.
Title: to skin a cat (m20 flywheel swap)
Post by: Bunta on March 01, 2007, 08:15:14 PM
so if you need change the toothed rings or the starter gear, use m20 clutch/flywheel(lightened) and 323tob your made in the shade?
Title: to skin a cat (m20 flywheel swap)
Post by: franz on March 01, 2007, 10:54:52 PM
this is the first time hearing this
what do you gain by chaning the flywheel to a m20

lighter flywheel is good
but by how much lighter and what is the cost lightening a flywheel
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on March 01, 2007, 11:17:18 PM
Quote from: franz;20400
this is the first time hearing this
what do you gain by chaning the flywheel to a m20

lighter flywheel is good
but by how much lighter and what is the cost lightening a flywheel


the stock M42 dualmass flywheel is 27lbs
The M20 flywheel can be taken down to 12-15lbs  

I dont know about the cost as I'm doing mine myself.  I would expect it to be under $50
Title: to skin a cat (m20 flywheel swap)
Post by: nickmpower on March 02, 2007, 12:55:05 AM
when is this going to be running? let me know if you figure out a starter to use. Mine hits the flywheel a tad since im not using the spacer, but i think an m2 one might work. I wont be home for a month so if you figure out something let me know.
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on March 02, 2007, 03:27:12 AM
Quote from: 2002maniac;20403
the stock M42 dualmass flywheel is 27lbs
The M20 flywheel can be taken down to 12-15lbs  

I dont know about the cost as I'm doing mine myself.  I would expect it to be under $50


Will you balance it by your self?
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on March 02, 2007, 10:40:14 AM
Quote from: nickmpower;20413
when is this going to be running? let me know if you figure out a starter to use. Mine hits the flywheel a tad since im not using the spacer, but i think an m2 one might work. I wont be home for a month so if you figure out something let me know.


stock starter should work with the 42 gear on there.  You can see in my sketch that the location of the gear on the flywheel is the same (1mm difference)
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on March 02, 2007, 10:41:50 AM
Quote from: romkasponka;20415
Will you balance it by your self?


no, the machine shop that bored my block is going to balance the bottom end with the flywheel and pressure plate installed.

nick,
  it wont be running until my motor is built.  mid-summer probably.
Title: to skin a cat (m20 flywheel swap)
Post by: black318i on March 04, 2007, 01:05:46 PM
Anyone know how much HP a stock m20 Clutch is good for?
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on March 04, 2007, 02:17:51 PM
Quote from: black318i;20527
Anyone know how much HP a stock m20 Clutch is good for?


there was no problem with 240hp , sachs 325ix kit....
Title: to skin a cat (m20 flywheel swap)
Post by: nickmpower on March 04, 2007, 03:09:27 PM
Quote from: 2002maniac;20421
stock starter should work with the 42 gear on there.  You can see in my sketch that the location of the gear on the flywheel is the same (1mm difference)


o yeah. The problem i have is that the m20 gear is longer then the m42 gear
Title: to skin a cat (m20 flywheel swap)
Post by: D. Clay on March 04, 2007, 08:23:15 PM
So:
1) Swap M42 ring onto M20 flywheel
2) Machine .23 to .35 from engine side of M20 flywheel
3) Balance flywheel
Anybody know how closely it needs to be balanced? Could you do a cleanup pass on the lathe and accomplish the balancing?
What 323i TOB is required.
Title: to skin a cat (m20 flywheel swap)
Post by: rob_e30 on March 05, 2007, 08:19:28 PM
Quote from: 2002maniac;20381
I also discovered that if you have the flywheel lightened on the engine side, you dont need to space out the M20 flywheel as described in a few of the writeups.  


Yep, this works and boy was I pleasantly surprised (I had not seen this thread yet)!  M20 flywheel is down to about 12.5lbs and I'm using an M20 starter along with the transmission that was in the car (from a 325i) so no other changes.
Title: to skin a cat (m20 flywheel swap)
Post by: nickmpower on March 05, 2007, 11:00:15 PM
Quote from: rob_e30;20640
Yep, this works and boy was I pleasantly surprised (I had not seen this thread yet)!  M20 flywheel is down to about 12.5lbs and I'm using an M20 starter along with the transmission that was in the car (from a 325i) so no other changes.


so is the starter bolted up and you know the pinion doesnt touch the flywheel? if so, sweet
Title: to skin a cat (m20 flywheel swap)
Post by: rob_e30 on March 06, 2007, 08:42:36 AM
Quote from: nickmpower;20660
so is the starter bolted up and you know the pinion doesnt touch the flywheel? if so, sweet


I was unaware that this was a concern.  I don't recall seeing this as an issue in the threads I read, but I certainly could have missed something.  I thought that the M20 flywheel and M20 starter could be transfered as a set?  I've not bolted up the tranny yet but expect to this week.

Any additional insight is appreciated.
Title: to skin a cat (m20 flywheel swap)
Post by: nickmpower on March 06, 2007, 12:53:52 PM
well i didnt need to use a spacer with my jb racing flywheel and my m42 starter with m20 pinion hits the flywheel, as the m20 pinion is longer then the m42 pinion. it needs about 1mm more room. if you could tkae a pic of your starter i could probably tell you if it will wok
Title: to skin a cat (m20 flywheel swap)
Post by: rob_e30 on March 06, 2007, 04:26:49 PM
Well I'm using a complete M20 starter, as pictured here...
Title: to skin a cat (m20 flywheel swap)
Post by: nickmpower on March 06, 2007, 06:26:20 PM
he is mine
Title: to skin a cat (m20 flywheel swap)
Post by: nickmpower on March 06, 2007, 06:31:01 PM
looks like the m20 one will work fine, though its hard to tell exacly as their end cases are different. You might want to to take the motor of the starter off so you can spin the gears then set the starter in the bellhousing and spin it to make sure they dont touch, thats what im going to do.

let us know when you get it bolted up
Title: to skin a cat (m20 flywheel swap)
Post by: 2002maniac on March 06, 2007, 07:49:44 PM
update.  

Well, this isnt going to be as easy as I thought.  The ID of the gears is different and I'll have to turn down the OD of the flywheel to get it to work.

It will probably be easiest for most to just use the M20 pinion gear.
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on March 07, 2007, 04:23:57 AM
Is it posible to fit stock starter motor if m20 flywheel gear was replaced by M42?
Title: OT
Post by: romkasponka on March 07, 2007, 06:57:41 AM
(http://img141.imageshack.us/img141/1249/img0003mediummf1.jpg)
Title: to skin a cat (m20 flywheel swap)
Post by: steve321 on March 07, 2007, 12:56:09 PM
what sort of weight is the M20 wheel then? i have an M40 flywheel to go into my 318is, but i have turned alot off or it, so mine weighs about 7.3kgs, i believe the M40 is a straight swap for the M42, but i hav'nt got mine fitted just yet.

steve
________
MERCEDES-BENZ M275 ENGINE (http://www.mercedes-wiki.com/wiki/Mercedes-Benz_M275_engine)
Title: to skin a cat (m20 flywheel swap)
Post by: steve321 on March 07, 2007, 12:58:51 PM
standard M40 (http://i34.photobucket.com/albums/d117/stevemitchell321/M40flywheelstandard.jpg)

my M40 one
(http://i34.photobucket.com/albums/d117/stevemitchell321/flywheel2.jpg)

steve
________
Infants wellbutrin (http://www.classactionsettlements.org/lawsuit/wellbutrin/)
Title: to skin a cat (m20 flywheel swap)
Post by: johna on March 07, 2007, 04:58:55 PM
M40 flywheel was simple replacement for me. Used shorter M40 flywheel bolts and M40 clutch kit. Wish I had reduced weight like you have though as the flywheel didn't make much difference.
Title: to skin a cat (m20 flywheel swap)
Post by: Jimmy Lewis on March 07, 2007, 09:01:30 PM
If anyone else attempts this and finishes before 2002maniac please share the results. This seems much less of a headache than trying to deal with modifying the starter as seen in m42boy's thread. Good deal.
Title: to skin a cat (m20 flywheel swap)
Post by: Jimmy Lewis on March 07, 2007, 09:02:02 PM
If anyone else attempts this and finishes before 2002maniac please share the results. This seems much less of a headache than trying to deal with modifying the starter as seen in m42boy's thread. Good deal. :cool:
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on March 08, 2007, 03:23:59 PM
Lightening flywheel by Lancia guru Guy Croft.

http://www.guy-croft.com/viewtopic.php?t=570

http://www.guy-croft.com/viewtopic.php?t=668&highlight=flywheel

http://www.guy-croft.com/viewtopic.php?t=607&highlight=flywheel
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on March 15, 2007, 11:48:03 AM
(http://img253.imageshack.us/img253/3280/img0004mediumtr9.jpg)

(http://img443.imageshack.us/img443/9065/img0005mediumgk1.jpg)

(http://img253.imageshack.us/img253/205/img0006mediumaq4.jpg)

don't know weight yet..
Title: to skin a cat (m20 flywheel swap)
Post by: steve321 on March 15, 2007, 02:30:50 PM
whats that one, an M20 one? looks like it would be well light

steve
________
Does cocaine help you study (http://www.rehab-forum.com/ritalin-rehab/5752-does-cocaine-help-you-study.html)
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on March 15, 2007, 03:25:34 PM
Yes, it's m20 flywheel, but slightly lightened.. :)
Title: to skin a cat (m20 flywheel swap)
Post by: rob_e30 on March 16, 2007, 10:09:50 AM
The M20 lightened flywheel with the M20 starter and no spacers, etc. seems to be fine.  I've bolted it all up and cranked it a few times.  Engine is not running yet as I need some software and fabrication work for the intake and exhaust but it's coming along!
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on October 13, 2007, 12:03:02 PM
My m20 flywheel (with 0.5mm preload) installed and runing with: m20 flywheel bolts, M42 starter motor, m20  325 free wheel pinion which was shortened to M42 free wheel pinion dimensions, 325 sachs clutch, 325 TOB. Everything works fine ;)

5.4kg flywheel + 7kg clutch = 12.4kg

http://romkasponka.blogspot.com/2007/10/sankabele.html

p.s. It is with E36 gerabox.
Title: to skin a cat (m20 flywheel swap)
Post by: Vladi on October 13, 2007, 12:47:00 PM
I didn't machine my flywheel before installing it...looks like i'll have to do it this monday...:mad:
(http://i214.photobucket.com/albums/cc92/184S1/PA131085.jpg)
(http://i214.photobucket.com/albums/cc92/184S1/PA131088.jpg)
(http://www.m42club.com/forums/%5BIMG%5Dhttp://i214.photobucket.com/albums/cc92/184S1/PA131088.jpg%5B/IMG%5D)
(http://www.m42club.com/forums/%5BIMG%5Dhttp://i214.photobucket.com/albums/cc92/184S1/PA131085.jpg%5B/IMG%5D)
Title: to skin a cat (m20 flywheel swap)
Post by: ispierrot on October 13, 2007, 03:34:11 PM
Hello
I just changed the gear in the starter to make the conversion.
(http://img515.imageshack.us/img515/1313/volantmoteur140ma4.th.jpg) (http://img515.imageshack.us/my.php?image=volantmoteur140ma4.jpg)(http://img138.imageshack.us/img138/992/volantmoteur141pp8.th.jpg) (http://img138.imageshack.us/my.php?image=volantmoteur141pp8.jpg)
Title: to skin a cat (m20 flywheel swap)
Post by: Shift_Now on January 05, 2008, 05:17:07 PM
So How has it been decided that the flywheel should be balanced after it is machined?  Would your avarage machine shop be able to balance it, without needing to balance it on the crank?
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on January 06, 2008, 02:36:39 PM
Quote from: Shift_Now;40504
So How has it been decided that the flywheel should be balanced after it is machined?


Yes.
Title: to skin a cat (m20 flywheel swap)
Post by: Shift_Now on January 06, 2008, 05:03:09 PM
But can a machine shop balance it? or does it have to be balanced with it attached to the crank?  Sorry for all of the questions, I just want to cover all of my bases before I have the flywheel machined
Title: to skin a cat (m20 flywheel swap)
Post by: romkasponka on January 07, 2008, 02:36:03 PM
It would be better to balance it with crankshaft if your engine is disassembled but you can balance only flywheel...
Title: to skin a cat (m20 flywheel swap)
Post by: pbgd3skier on January 12, 2008, 01:30:09 PM
best to balance flywheel, then balance assembly.

If you balance the assembly with the crank out of balance and the fly wheel out of balance it will blow itself apart at high rpm.

Remember that some people balance their wheels w/ tires brakes and axle.
Title: to skin a cat (m20 flywheel swap)
Post by: Appletree IS supercharged on February 06, 2009, 11:36:27 AM
Just to clarify, if you use an M20 flywheel lighten it to remove the step from the block side and then fit the M42 ring gear to it  ( after the FW been moded to take it) you dont need the spacer and you can still use the stock m42 starter motor, and then just buy a 325 clutch assembly and a e21 323 T/O bearing.

another thing ive been thinking of is if you do the above and dont use the spacer then the flywheel is then going to be the thickness of the spacer further towards the block, will this cause a problem with the starter?

2002maniac did you use the m42 starter motor and was it with or without the spacer?

Cheers Matt
Title: to skin a cat (m20 flywheel swap)
Post by: e30guydownunder on February 08, 2009, 05:48:51 PM
I have an early e30 323i flywheel (its 2 kilos lighter than the average m20 flywheel, so is 6kg from the factory, no need to lgihten :)) And will be bolting a 323i starter straight to the engine. Was intending to run the 3mm spacer to maintain factory spacing of the ring gear.

I'm also intending to run the m20 TOB as i got one with the clutch kit. I will be modifying the clutch fork if neccessary to get the extra travel as the e21 323i TOB was $190!!!!. But really i just think it will mean you have to push the clutch pedal further. Will have to find out with some testing yet.

When i am doing stage 2 or 3 of the build i will consider removing the flywheel and doing the modifications neccessary to fit the m42 ring gear...the m20 starter motor is 4kilos heavier!