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Posted: Wed Sep 24, 2008 4:06 am
by rob0r
1 step forward, 3 steps back. It was confirmed the E36 mounts are too wide for the E21 chassis, but by a stroke of luck M20 mounts do bolt onto the M50 block on exactly the same place. There is a problem due to the engines sitting on different angles. The M20 mounts aren't particularly suitable as the exhaust side mount is so far low that when the engine is sitting in the middle of the bay and at the correct angle the rubber mount actually sits off the subframe. I plan to get round this by extending the subframe platform. Accordingly, the inlet side mount is going to be very tall, but I'm less worried by that.

E36 vs M20 mounts
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M20 exhaust side mount on M50 block
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M20 Inlet side mount, there's a inlet manifold brace that bolts on behind the mount, but I ground it down so it would clear
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Damn it! I won't be able to use my cheap firm mounts since the M20 mounts are too thick
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Where the exhaust side mount will sit
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Since my car will not be running aircon and all the gubbins had been removed, it seemed stupid to keep the aircon pulley on the crank which takes valuable radiator space away. Since the pulley would be gone, something needed to be done with bolt length. One option was shorter bolts, another was to use spacers, but I chose to butcher the pulley itself.

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Gave it a blast of satin black, looks good I think
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Final engine position
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Posted: Wed Sep 24, 2008 10:08 am
by thetomc
Good work Rob, keep at it!!

Posted: Wed Sep 24, 2008 10:49 pm
by murran
you certainly dont hang about!
looking good. 8)

Posted: Fri Sep 26, 2008 12:25 am
by rob0r
Subframe mutilation

To get the engine to fit where I wanted it and not make or modify standard block mounts, I decided to make the bold move and modify the subframe. I say modify, I actually mean to cut and weld the hell out of it.

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Let the cutting begin!
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Welding
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Ground back
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Tomorrow's challenge
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Posted: Fri Sep 26, 2008 2:18 am
by Jason_323i
Hi Rob

Have you ever had a chance to compare the width of an e21 chassis rails to the e30 ones

Jason

Posted: Fri Sep 26, 2008 11:27 am
by rob0r
I haven't, although I can if you need me to since I have one that's engineless at the moment.

Posted: Sun Oct 05, 2008 10:08 am
by Tikky
For job, max respect :D

I did the similar job with flywheel(M20, 6.4kg) and put M50 gearbox, only what I must is change the starter gear wheel!!
But when I was try put the M20 gearbox on M50, they fit, but they have a diferent angle, how you make shifting arm???

Posted: Sun Oct 05, 2008 2:33 pm
by rob0r
Cheers :)

I have a 525i M50 gearbox, but I heard the ratios combined with the 323i diffs aren't ideal, are you using a 325i box? I also have a spare M42 gearbox which is a direct fit, but I've chosen to use the speedo drive so hence the M20 dogleg I have lying around. When bolted up, the angle isn't that different and just looks a little off centre, I can even get away with bolting up the box on standard mounts and letting the rubber mount take the minimal twist. The linkage will have to be custom, but I'm not too worried, especially as I have to do the exhaust manifolds first...

Posted: Sun Oct 05, 2008 11:49 pm
by --ALPINA--
Thats top job rob, i like that, the pictures are very good!!!! keep up the good work there!!!!



j

Posted: Mon Nov 03, 2008 11:11 pm
by drjim
Rob

Instead of arsing about with a custom made linkage for the gearshift, could you not just alter the angle the engine sits at - like Tom did with his M42 swap? You're doing custom mounts for the engine anyway...

Just an idea from a potentially interested party :wink:

Jim

Posted: Mon Nov 03, 2008 11:39 pm
by rob0r
With the engine sat on the M20 arms, none of the existing holes on the subframe lined up. Rotating the engine in preference to the angle of the gearbox is definitely possible but I chose not to go that route for a number of reasons. With the M20 mounts the rubber engine mount wanted to sit on the subframe on the exhaust side so I thought that was quite convenient to mount the engine like that. Another reason being how low my car will be, and the angle of the sump. Tomc has cut and welded his sump to suit, but I don't have the skills or tools to do that. But I do have the tools and skills to fabricate the subframe and custom mounts though. Another reason is that I reckon, unless you want the engine a lot further forward than mine is, the gear linkage will have to be shortened considerably anyway. Also I have been able to get away with bolting the gearbox as normal as it's not actually that far out. To be honest I'm considering the gear linkage and the mounting of the engine to be discretionary, I'm more worried when I have to chop up my M52 exhaust manifolds!

I can see the positives in doing what you've said though. As well as the gearbox angle you'll gain clearance for the exhaust manifolds between the block and the steering rack, and the manifolds will be slightly further away from the steering link.

On a different note, nothing has been done lately since I went on my hols for two weeks and now I've got back I've been happily insulating my garage... I hoping to get some time in next week though. I've ordered four hockey pucks, which will become my latest engine mounts 8)

Posted: Thu Nov 06, 2008 6:05 pm
by tommi_e21
in the right hand drive vehicles i have a big ass brake servo in the way on the inner wing, if i have to jack the engine over onto the inlet side to clear the servo which engine mounts will be best? would it not be easyer to fabricate custom engine mounts? i really want to do this whole conversion but i never see it done on rhd drive vehicles. any chance you have a servo which you could line up in your engine bay and show me how far clear it is of your engine? cheers T

Posted: Thu Nov 06, 2008 8:13 pm
by rob0r
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You can see how close it is with the M42, now add two cylinders and it's not going to fit. M20 mounts would be best for what you want since they rotate the engine further to the inlet side but I modified subframe so the sump was level. You would still need considerable fabrication though, and there's no guarentees you would be able to rotate the engine enough to clear the servo. Also consider the engine twists towards the servo on power.

This was a photo taken a while back, and I'll get another one. To be honest I just whipped off the servo and didn't even check it because I just don't think it would fit. Plus I'd like to fit a pedalbox just for the sake of it!

Posted: Thu Nov 06, 2008 8:29 pm
by Jason_323i

Posted: Thu Nov 06, 2008 11:13 pm
by tommi_e21
its good little report but again its for left hand drive model which doesnt help with my ol servo problem.