m20 flywheel on m42

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hoshy
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Tue Aug 21, 2007 11:59 am

Has anybody actually DONE it ?
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Dan318-is
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Tue Aug 21, 2007 5:17 pm

Gallafant?
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hoshy
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Tue Aug 21, 2007 5:24 pm

you tempted to get the parts together and do a group fit dan ?
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Dan318-is
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Tue Aug 21, 2007 5:27 pm

Group fit now that would be fun! Not lol im not sure ash. Have a butch on m42 club, its easy with the engine out but i reckon its a nightmare with it in! I have an m40 flywheel and a brand new clutch in garage waiting to go on but i cant be bothered to fit them at the moment.

Stuartgallafant had his engine out the car and so rightfully got on and did it (which i would if my engine was out of the car also!) but unless you plan to take the lump out i wouldn't bother. Don't you need a 323 throw out bearing and longer bolts etc etc etc?

Its also a question of how far you go when you have them out. Shifter bush etc. can all be done but it depends how deep your wallet is / access to ramps and tools i guess!
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hoshy
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Tue Aug 21, 2007 5:30 pm

I got quoted 120quid by the local garage to bolt it up assuming I got all the parts and it was a simple bolt up job.

I heard you need the bearing and either the m20 starter or the pinion from it and the 323 bearing too.. Hoped the 323 bearing was available from the stealers and the starter should be easy to find.

Didn't know about the longer bolts though. You sure?

Is the m40 fly an option too? bettter weight saving than the m20?
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Dan318-is
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Tue Aug 21, 2007 5:35 pm

Not sure about the longer bolts but i remember reading it somewere?

The m40 is allegedly 9.7 kils compared to the 12 kilos of the m42; its a straight swap and you could have it reskimmed etc before you put it on. The problem is some m42s had dual mass & some had m40 flywheels from what i have seen, there really is no way of telling until you get it all apart!

£120 sounds fecking cheap, is that your old mans garage?
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hoshy
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Tue Aug 21, 2007 5:40 pm

lol - na. My dad usually tells me to do it myself :) Then help once I've fucked it royally up.

if you can't tell if it's got an m40 in it or not til you open it... it it worth bothering with the swap?
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Tue Aug 21, 2007 5:47 pm

Well thats the debate ash!! Half the reason why im waiting until my clutch goes / needs doing. I remember tim saying that two engines he has pulled have both had m40 flywheels in! But gallafants definatly had an m42 one in. All this talk of alluminium flywheels is good but would you spend £450 quid on one and put a 3kg one in a road car? I am not one to be bothered about comfort or noise in the slightest but 3kg is race spec in my opinion.

Be a hero and do it hosh!
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hoshy
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Tue Aug 21, 2007 5:51 pm

lol - I'll get done. At the moment I'm chatting with my house mate about getting a spare m42 and doing all the work out of the car, SC included. So would probably do the m20 fly also. If it'll happen or not is a different story :)
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Tue Aug 21, 2007 6:09 pm

8O
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hoshy
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Tue Aug 21, 2007 6:24 pm

yeah. should be sweet. I've got the space for it now. Could just about muster up the cash. Would be a nice project to make a sweet blown m42 - but... I dunno if I want to take such a big project on.. That's why i wanna see if my house mate wants to get involved.
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Tue Aug 21, 2007 8:54 pm

I've still got that block which you could use to make things easier with the flywheel conversion... :D
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Tue Aug 21, 2007 8:56 pm

I am in the middle of putting an M20 flywheel into my 318is, the clutch has gone so why not!

Try the following link - it has pictures and a comprehensive guide:

http://www.blackforestindustries.com/m20flywheel.htm

I have the flywheel, the cluch assembly but I'm having nightmares trying to find the right release bearing - I have one on the desk in front of me which is allegedly for a 323 but it looks completelly wrong!

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Tue Aug 21, 2007 8:58 pm

Daf318is wrote:I am in the middle of putting an M20 flywheel into my 318is, the clutch has gone so why not!

Try the following link - it has pictures and a comprehensive guide:

http://www.blackforestindustries.com/m20flywheel.htm

I have the flywheel, the cluch assembly but I'm having nightmares trying to find the right release bearing - I have one on the desk in front of me which is allegedly for a 323 but it looks completelly wrong!

Daf
Thats the sight i was looking for but couldn't remember :)
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hoshy
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Tue Aug 21, 2007 9:43 pm

Theo325 wrote:I've still got that block which you could use to make things easier with the flywheel conversion... :D
I've still got it in mind mate.

What sort of condition is it in?
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hoshy
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Tue Aug 21, 2007 10:09 pm

Daf318is wrote:I am in the middle of putting an M20 flywheel into my 318is, the clutch has gone so why not!

Try the following link - it has pictures and a comprehensive guide:

http://www.blackforestindustries.com/m20flywheel.htm

I have the flywheel, the cluch assembly but I'm having nightmares trying to find the right release bearing - I have one on the desk in front of me which is allegedly for a 323 but it looks completelly wrong!

Daf
Great write-up. Thanks for the link.

Can you not get the bearing from the stealers?
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Dave_M3
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Tue Aug 21, 2007 11:00 pm

I'm doing mine when the Clutch goes. Can get a smell off it the odd time.
I'm going to do it with the engine out altogether.

That way I'll do the flywheel and a Z3 rack in one go winkeye
Last edited by Dave_M3 on Tue Aug 21, 2007 11:08 pm, edited 1 time in total.
M42 rightness above 6500rpm, nobody can hear you scream
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hoshy
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Tue Aug 21, 2007 11:04 pm

Dave_M3 wrote:I'm going mine when the Clutch goes. Can get a smell off it the odd time.
I'm going to do it with the engine out altogether.

That way I'll do the flywheel and a Z3 rack in one go winkeye
nice :)

done much else to the car ?
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Dave_M3
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Tue Aug 21, 2007 11:24 pm

No not much so far only just service to get ther past the NCT next week or the week after

It was Beemertoms car off here up to a month or too ago.
I must put up a few pics sometime with the few jobs I'll be doing to it

I have a list already on E30owners.com over here in IRL.

http://www.e30owners.com/forums/showthr ... #post15916

Should be a nice little car when finished
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Dan318-is
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Tue Aug 21, 2007 11:28 pm

How do you plan to do electric pop out rears mate?
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Tue Aug 21, 2007 11:37 pm

lol, thats really gettin quite alot of interest winkeye

Instead of Hijackin this thread I'll start a new one on it altogether :wink:
Besides I want to get some opinions on if it will work anyway
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Tue Aug 21, 2007 11:40 pm

I would like to see it work!

Sorry for the hijack ash!
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hoshy
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Tue Aug 21, 2007 11:44 pm

interestin' stuff. it will be nice. I like the sound of the elec pop-outs too :)
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Wed Aug 22, 2007 12:19 pm

I've delt with 3 M42s so far and all have had the M40 flywheel.

Got my engine out at the moment but i've decided to go a bit extreme since i don't actually drive mine loads and certainly don't do much town driving. I've got a JB flywheel on its way, been looking around and not seen anyone really comment on these apart from how well made they are so i'll let you all know what it's like once it's up and running.
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hoshy
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Wed Aug 22, 2007 1:21 pm

hmm - interesting. so there's at least a chance I've got an m40 fly wheel. so the question becomes - what's the weight difference between an m40 and m20 fly ?
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Wed Aug 22, 2007 11:15 pm

Heard about some Fly on the M42club that makes 4th gear feel like 3rd after its put in 8)
Costs a sh!t load I suppose. Meh, my M20 will do just fine. Maybe I might try something abit more interesring on my track car then. Release bearing all ready going so I think she is crying out for the 323 one winkeye
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thetomc
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Thu Aug 23, 2007 10:58 pm

I've done this conversion this week. I used a lightened e21 Alpina C1 flywheel.
Only fiddly bit is changing the pinion on the starter motor. This needed to be swaped out for a e21 323i pinion. If anyone wants details of this I'm quite happy to expand on the subject.
Diffenence in mass between the two flywheels is ridiculous!!
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Kos
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Thu Aug 23, 2007 11:04 pm

Kedge wrote: I've got a JB flywheel on its way
:clap:

nice one, you wont regret it, and its bolt on aplication which enginered to work proberly

i cant see the point in dicking about with the m20 on, its still heavy. with the JB ones you will have asignificant impovement
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hoshy
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Fri Aug 24, 2007 2:35 pm

Kos wrote:
Kedge wrote: I've got a JB flywheel on its way
:clap:

nice one, you wont regret it, and its bolt on aplication which enginered to work proberly

i cant see the point in dicking about with the m20 on, its still heavy. with the JB ones you will have asignificant impovement
I hear what you're saying Kos - it's all about degrees of improvement. A balance of weight, cost, effort.

I was looking only for stuff that I can bolt in, no machining.

Have you got the various weights ?
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Fri Aug 24, 2007 6:05 pm

The M42 Dual Mass is 27lbs, The M40 one which is the only one i have seen on an M42 is 22lbs, i think the M20 is 17lbs and the JB one is 8lbs! 8)

Should be just over a week by the time i get mine, Kos have you driven a 318iS with one of these fitted yet?
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Mon Aug 27, 2007 1:40 am

never order or fitted one to my IS, it was the next thing i would have done if i kept it, and if i every buy an other one its one thing that i will deffo do.
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Mon Aug 27, 2007 11:25 am

jb do a 8lbs flywheel for M20's too :D
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