taking parts from M20 to put on m42?

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WhitbysE30

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taking parts from M20 to put on m42?
« on: February 15, 2013, 10:20:52 AM »
I posted this same question in another forum only got one reply tho.

so my buddy is going to part out his modded 325is, so i was wondering what parts should i take to add any type of performance to my 318is? i know most part won't fit my m42, but what parts will? i know taking the flywheel will help make some of the first gears quick but is there anything else?

DesktopDave

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taking parts from M20 to put on m42?
« Reply #1 on: February 15, 2013, 04:09:27 PM »
If you take the flywheel, be sure to keep the starter too.  Early and late units don't match - ring gear and starter are a different pitch.

I'd definitely grab the diff - I have a 3.73 medium case LSD from an '87 325is in mine - great upgrade for highway cruising.  Bolts right in.  I'd grab the whole rear subframe while I was at it - overhaul one & swap it all out at once.  Driveshafts are the same as well.

Lots of other chassis stuff will swap, of course.  Cruise control can be made to fit, gauge clusters are the same except for the coding chip.  I'm not sure of anything else, to tell you the truth.  Maybe the engine accessories?  P/S pump & alternator look similar, but I have no firsthand idea if they'd work.  Many Bosch alternators use the same internal parts inside different case halves.
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

keflaman

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taking parts from M20 to put on m42?
« Reply #2 on: February 15, 2013, 04:56:35 PM »
13 Button OBC...Dave.:D

There's a DB 325is at a nearby junkyard that I'd like to grab the diff out of, but it's sunk down in the clay up to the rocker panels and behind 5 or 6 rows of cars.

DesktopDave

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taking parts from M20 to put on m42?
« Reply #3 on: February 15, 2013, 06:48:04 PM »
I'm going to figure that swap out one of these days, unless I get an Arduino & do it first.  

How much cooler would an E30 be with a small helping of newer BMW tech?  OTOH we never have to replace piezo injectors, suffer through burned-out pixels or have to overhaul VANOS units...or fight with an iDrive system...
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

WhitbysE30

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taking parts from M20 to put on m42?
« Reply #4 on: February 18, 2013, 09:21:24 AM »
Thanks for the help man

bujna

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Re: taking parts from M20 to put on m42?
« Reply #5 on: March 21, 2013, 11:51:47 PM »
See if he's running upgraded brakes, and suspension too!

IlovM42

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Re: taking parts from M20 to put on m42?
« Reply #6 on: March 22, 2013, 02:48:30 AM »
80° thermostat from M20 can be use on M42, but not sure you want to put an old one instead of a new one