Dual mass flywheel in an M50..it's not what you think.

[joshh]

As far as I can tell the E flywheel is exactly the same as the I flywheel just thicker.
I had the backside of the flywheel machined off already 6mm.
As long as the E flywheel is used the E clutch assembly should be used as well. I really don't know if the assemblies from the I and E are the same because Real OEM has all E30's listed with a dual mass flywheel, which is incorrect.
The motor came out of an auto so I also had to buy a pilot bearing and don't have a slave for the M50.

[Beej '86 325es]

Out of curiosity, what month of '86 was your 325e made?

Mine was made 2/86, and has what I THINK is a single mass flywheel that I had lightened by Metric Mechanic:

[joshh]

That looks exactly like the one I have. Now I don't know if it really is single or dual...searching time again.

[joshh]

Ok, I think I found out. Technically these are not "dual" mass flywheels. They are twin mass flywheels. No moving parts so they are exactly the same as the I flywheel but they are thicker and thus heavier.

[Beej '86 325es]

Interesting. I've been trying to figure that out for a long time. Thanks!

Mine was shaved from 24 lbs down to 12 lbs, can you tell by looking where the weight was shaved from?

[joshh]

I can tell nothing was taken from the front at all so you must have had the guy take it off the back. And inset the back as well for that much to be taken off.

[tjhartge]

Interesting. I've been trying to figure that out for a long time. Thanks!

Mine was shaved from 24 lbs down to 12 lbs, can you tell by looking where the weight was shaved from?

beej,

do you have any flywheel clutter sound, my pal's lightweight m20 flywheel sounds like its a diesel car, it only happens when the engine is at its optimum running temp
he is using MTLs , was going to suggest he change to 75W140NS

which slave pump did you use? is it with a longer rod?
i'm thinking there is some freeplay in the clutch/flywheel causing the sound, its nothing major, just abit irritating at times, as the engine is very smooth and quiet

[Beej '86 325es]

beej,

do you have any flywheel clutter sound, my pal's lightweight m20 flywheel sounds like its a diesel car, it only happens when the engine is at its optimum running temp
he is using MTLs , was going to suggest he change to 75W140NS

which slave pump did you use? is it with a longer rod?
i'm thinking there is some freeplay in the clutch/flywheel causing the sound, its nothing major, just abit irritating at times, as the engine is very smooth and quiet

Every once in a while, I'll get some clutch chatter, but that comes with having a lightened flywheel. I'm using MTL, but I don't think the tranny fluid would affect anything.

I actually don't have S50 in yet, but I'm planning on using the 260 tranny and 325es clutch slave. The shop is finally going to start working on my engine after Christmas.

[tjhartge]

check this out

http://www.uucmotorwerks.com/html_techtip/techtips/tranny_rattle.htm

i suppose the rattle could be dampen by using proper fluid, but since the 260 box uses the normal GL4 grade fluids rather than the newer boxes that uses ATF, then it would be a straight usage of 75W140NS then.....

any thoughts on this?

http://www.uucmotorwerks.com/flywheel/gear_rattle.htm

this tech article really makes me wonder why i do the crazy stuff and then go and find a cure for the crazy stuff that i did....

[motors4me]

There is a production date split on 5/86. Cars built before May have a conventional flywheel, and cars built from May on have a dual mass unit. The dual mass flywheel consists of a primary mass with starter ring gear, a spring damper system, and a secondary mass with contact surface for the clutch drive plate.