Messages

1

Photoshop, Media, & Artwork / M42 Autocrossing

« on: July 04, 2012, 06:22:28 PM »

318is (1991) with M42 is in G-stock.   Modifications may bump the car into STX or DSP.  Note that in DSP definitions this car is described as "3 series (16V, NOC)"       NOC means Not Otherwise Classified, or in other words, if you don't find your car in any other subclass of SP.

2

How-To's / DIY M20 flywheel conversion

« on: April 06, 2012, 09:51:56 PM »

So i've been reading up on flywheels for our cars and would love to get a lighter one. A direct fit solution seems to be only from JB @ turner motorsport for ~$630. These are the most expensive of all other E30 lightened flywheels. Even more so than E30 m3's.

Ive been reading through some M20 conversions, and this seems like a viable solution. However, i dont see many people posting their end costs for the entire job, in parts, or whatever.

So, how much cheaper is the M20 swap compared to a direct fit job? If significant then for me its worth it. If only slightly then why bother?

The price depends on what flywheel you work with.  If you start with a 13lb flywheel from a '79 323 then it depends on whether you buy this new or used.  I started with a used one for $120, got it resurfaced for $30. If you start with a 325 M20 flywheel and get it machined down to 12 lbs, it might cost you $150.


11221264517     used 323 flywheel       $150
OR
11221264517     new 323 flywheel      $315.95
OR
325 M20 flywheel     used + machining   $150(estimate)
PLUS
21211223174    clutch disk      $84.95
21211223026    pressure plate   $64.95
21511204525    throw-out bearing   $57.95
11221717840    flywheel bolt      $3.95 each x 8
07119901023    pressure plate bolt   $0.95 each x 6
Used starter from ’89 325 (Bosch)     $50


Other parts you might want:

pilot bearing  11211709681  (or11211720310 depends on prod date)  $13.95
rear engine seal 11 14 1 706 785     $10.95
locating dowel 11 11 1 743 118     $1.95
exhaust gasket 18 30 1 711 969     $18.95
exhaust nuts 18 30 1 737 774       $1.50 each x 4

Now, bear in mind that this is not just a lighter flywheel that you are getting, it is also a new upgraded clutch.  You don't get that for your cost of a custom aluminum flywheel.

3

Engine + Driveline / 4.10 LSD now slipping

« on: February 09, 2012, 11:15:41 AM »

Harv - how does the Torsen do in everyday driving?  Does it help much with snow?

Sorry, Dave but I couldn't say.  This car isn't a daily driver so It doesn't go out in the snow, and I'm pretty easy going on the street especially in the rain so it never really gets pushed enough to notice.

4

Engine + Driveline / 4.10 LSD now slipping

« on: February 08, 2012, 08:39:50 PM »

Thanks for clarifying Dave.  I also wanted to mention that the improvement of going from an open diff to the Torsen was, shall we say, "Mind-Blowing!", in autocross competition.  Its also nice to know that a Torsen doesn't wear out cause it has no clutch plates, and it doesn't cause any sudden push or pull of any sort at any time going into, apexing or coming out of a corner.  Very smooth.  

The only thing that it does cause is confusion.  My mechanic had the car up on a hoist and did the classic check for an LSD by spinning one wheel by hand.  That test doesn't work with a Torsen, so he said "hey, you got ripped off, that's not an LSD".  Driving is the real proof, and yes it really is an LSD.

5

Engine + Driveline / 4.10 LSD now slipping

« on: February 08, 2012, 08:05:35 PM »

Guys, I'm puzzled by your mention of changing the rear cover on the Z3 Torsen diff.  I've got a stock Z3 torsen diff in my '91 318is and it was a straight bolt-in, with no fit problems.  Why change the rear cover?

6

Engine + Driveline / Lightweight flywheels..how light is too light?

« on: September 20, 2011, 11:48:53 AM »

I also have the 13lb flywheel from a 323 with the M20 clutch and I have no issues at idle at all.  The idle seems unchanged from stock.

7

Exterior / Restoring faded paint - help

« on: August 01, 2011, 09:11:48 PM »

If you have time to do some reading, this forum might be useful:

http://forum.roadfly.com/forums/22-Detailing-Forum

8

How-To's / DIY M20 flywheel conversion

« on: June 26, 2011, 02:29:11 PM »

Couple of points of clarification.  I have a 1991 E30 318is.  I want to put in an aftermarket lightweight flywheel and clutch.  
In order to do the conversion do I need:
1) 323i or 325i throw out bearing?
2) 12x22mm or 12x28mm Flywheel bolts?
3) Longer slave cylinder rod or stock M42 slave cylinder rod?
4) Which side does the spacer go on (closest to engine or tranny)?
5) Any other parts needed other than 325 starter pinion gear?
6) Is there a writeup on swapping the starter pinion gear?  It looks anything but straight forward.  
7) What is the part number for the pinion gear?

-Scott

Scott, I'm a bit confused.  Your list suits the installation of an M20 flywheel and clutch, but you say that you want to put in an aftermarket lightweight flywheel and clutch.  Aftermarket, to me, means an aluminum flywheel, and to my knowledge these are usually tailored to the car.  So, for example, if you are going to purchase a unit made specifically for your M42 and Getrag 240, then most of your list is unnecessary.  I guess perhaps you are thinking of a flywheel made for the M20.  Can you confirm this?

9

Engine + Driveline / Power mods for the M42

« on: May 11, 2011, 07:26:05 PM »

wow i didn't realize the steel flywheels were so light. i was looking to the 9lb aluminum ones, but at $450, i've been hesitant, and it'd be the most expensive part I've put on the car to date.  think I'll go with a steel one and have it lightened as much as possible. it does have a limited slip diff, and i agree, it's an excellent upgrade. makes a world of difference when you start pushing the car in corners

Indeed, this is why the conversion to an M20 flywheel and clutch is so popular, because it is relatively cheap.   You have to calculate the total including an M20 starter motor but if you do some research on this conversion on this site, you will find what you need.  

Don't rule out the 9lb aluminum one just yet.  The steel one can't be brought down to that weight as far as I know.  

The stock flywheel is dual mass.  The conversion to M20 changes to a single mass unit.  This means that you lose the flywheels ability to absorb shock and vibration.  With the M20 setup, this is dealt with by a different clutch plate that includes shock absorbing springs.  These springs are not found on the M42 clutch plate because they are not needed.  Changing both flywheel and clutch together to M20 type deals with this problem.  Now, if you were to change to an aluminum flywheel which is single mass, and you don't change the clutch plate then you have no element in the driveline to do that job of absorbing vibration.  I think this is why some that have done a conversion to aluminum flywheel (to flywheels made to fit M42) suffer additional noise, especially during idle, at least that's my theory.

10

Engine + Driveline / Power mods for the M42

« on: May 10, 2011, 09:56:07 PM »

don't need to upgrade the fuel pump, because the injectors operate at very nearly the same psi. the injectors are plug and play and do make a difference. nothing earth shattering but it is noticeable. the injectors are from the 5.0 mustang. i got mine for a '90 mustang GT with the 5.0L V8.

I have been absolutely satisfied with the power upgrades on my 91 318is. it is remarkably quick and a lot of fun. Personally i think the M42 is very underrated

i have done the following:
mustang injectors
advanced the intake cam timing by 6 degrees (big improvement in top end)
done a custom high flow cold air intake filter setup
Coil over pug conversion (excellent upgrade)
swapped in a slim electric cooling fan and ditched the heavy factory fan
dinan chip (a bit disappointed. will swap for a markD 93)
custom free flowing exhaust (big improvement, fantastic sound)
cleaned up all the vacuum lines, and made sure no breather lines feed back into the intake. (no more oil and hot air getting sucked back into the intake)
AC delete
Power steering delete
ABS delete
stripped the interior
lightweight front racing seats

One of the most important things you can do is just sort the controls. suspension should be tight and aligned, firm up the brake pedal, make sure the throttle linkage is free, clean the throttle body and manifold. Then your power upgrades will be all the more noticeable

the car's an absolute kick in the pants. i've gone for lightweight and instant response. on windy roads, very, very few cars can hang with it. will still do an aluminum m20 flywheel swap

Nice clean engine bay, good work!  The M20 flywheel swap is a good mod and the upgrade to the M20 clutch is a nice improvement too.  If you go this route, using an M20 steel flywheel, have it lightened as much as you can, like down to 11 or 12 lbs.  Mine is 13 lbs (stock flywheel from older 323i).  I would go lighter if I was doing it over again, perhaps a 9lb aluminum one.  

Are you running a limited slip diff?  That's a good mod if you don't have one.

11

Engine + Driveline / Pic comparison of 323i TOB vs 325i TOB

« on: May 10, 2011, 03:59:41 PM »

I can't for the life of me find the thread that has a comparison of all three TOB's sitting side by side.

Does anyone remember where or have a pic?

It was the 323i tob, 325i tob and 318i tob...

I remember those photos quite well, and thought I could find them, but after a long search, I'll be damned if I know where they are.  It was one of the longer threads, I think.

12

WTB/WTT / WTB: Dual Mass Flywheel

« on: April 19, 2011, 01:54:10 AM »

I was about to throw mine out but you can have it for nothing if you want to cover the shipping (from Canada, so more expensive, maybe as high as $45).  I believe it has about 85,000km on it but don't know for sure.  It was taken out to convert to lighter M20 flywheel.  Photos avail if you want.

13

For Sale / FS: New M42 motor mounts

« on: April 13, 2011, 02:53:03 PM »

What part no. is this and from what manufacturer?

14

General Topics / Feeler: M20 LW Flywheel & Clutch kit....etc

« on: April 10, 2011, 03:09:37 PM »

The 13lb-er is friggin awesome man. No increased effort really. I have the 323i, M20 clutch, pressure plate and 325i TOB on mine now.

Engagement is nice, pick up is great, pretty sure the only difference you'll notice is the wider grin on your face!

Glad to have another m42 again btw:

Just chiming in to add my "hear hear" to dude's comments.  The 323i M20 flywheel, around 13lbs, is a no-brainer.  No bad habits at all, its great.  If I were to do it all over again, I'd go even lighter than that.

15

Engine + Driveline / M42 single mass VS M20 single mass conversion

« on: March 03, 2011, 12:06:48 PM »

i badly need a clutch too!

a year or two ago i wanted to get (e21) 323i flywheel as someone else on here did.  but what clutch kit do I need with that, 323 or m20 (325i)

and would a 325i starter still work with that. i'm confused as hell :confused:
pelican parts catalog is further confusing me. i won't shop there again but they had reliable info..

Yes indeed, it is very confusing.  My experience is that for the E21 323i flywheel (which is what I used) the M20 clutch kit is a perfect fit.  See my list of part numbers in post #42 of this thread for details.

I also used a starter from a 325i, in fact a 325ix, and it fit correctly.