JB racing flywheel question

[OSM e30]

im wondering if i can us the JB racing m20 single mass flywheel on my m50? and then what clutch kit should i use?

[Mako18]

YES and use a m20 pressure plate, the clutch disk can be from either a e36 or e30. I used a m20 HD PP and e36 325 disk. The starter will then need to be a m20 325i starter and you'll use a e36 salve cylinder unless your using a getrag 260 then the e30 slave will work but I am assuming you'll be using the getrag 250.. This has all been covered but I am feeling helpful.

[Nick325is]

I'm running the JB racing flywheel and clutchmasters clutch kit for the m20. I'm using the m20 trans btw. Make sure you get the correct pilot bearing.

[madjurgen]

Im also planning on using my m20 JB ltw fw with my 24v, so I'll piggyback off this thread since the original ? has been answered. What are you guys doing about flywheel bolts when transferring the JB fw? I thought you were supposed to replace the bolts everytime, but OEM bolts are too short when using the steel spacer plate. And Im not about to ditch that and bear up against the Al. This last time I just reused the ones that came with the JB kit but was wondering what others did.

[mazur]

So let me get this straight. When using the stock getrag tranny, an E36 clutch may be used in conjunction with the M20 pressure plate and flywheel?

[Mako18]

Yes it works & the tranny shouldn't matter be it a 250 or 260. I belive the shafts have the same spline pattern. I am using the e36 325i clutch disk + m20 hd pp + m20 jb racing flywheel, no problems here with the 250 trans. PLEASE NOTE!!!! My car isn't moving under its own power yet but I have tested this setup by rolling the car while engaging and disengaging the clutch..again no issues. I don't predict any issues no hard racing here.

The clutch disks aren't very complex basically as long as the diameter is the same and the inside spline are the same or matches the corresponding tranny then its usable. The only other difference would be sprung or unsprung disks & of course material of the disk.

If you want something that grabs better or has a higher clamping load for more pOwA, then an upgrade of the pressure plate is a must along with a beefier disk. I have heard the stock e36 (325) disks don't like to be in the higher rpms some come apart I guess. My setup is just to get the car moving and sorting out other odds and ends then I will upgrade for future needs/mods..

Bolts.....I reused my bolts & never had a problem doing this with any other cars but thats up to you. For the power I will be putting out now there is no sense in uprgading but later I will replace or upgrade!!

[MIKe30]

Fuck this topic is so confusing. I need to find a transmission/swap guru. For 24v/g260 and m20 to 318 powertrain.

[318isbmw]

Fuck this topic is so confusing. I need to find a transmission/swap guru. For 24v/g260 and m20 to 318 powertrain.

Stick to what you know works. Don't worry about the others if it doesn't make sense. That being said, Mako, I believe the diameters are the same and believe you on all of that, but I'm leery about taking advice on using it on other cars before its ever been tested on on, actually at rpm and such.

[Roz]

What are you guys doing about flywheel bolts when transferring the JB fw? I thought you were supposed to replace the bolts everytime, but OEM bolts are too short when using the steel spacer plate. And Im not about to ditch that and bear up against the Al. This last time I just reused the ones that came with the JB kit but was wondering what others did.

I bought my 325 with a NV M50, which had a JB Racing Flywheel. When I replaced it with an S50, I called JB Racing. They said you can reuse their flywheel bolts, since they don't stretch.

[MIKe30]

Stick to what you know works. Don't worry about the others if it doesn't make sense. That being said, Mako, I believe the diameters are the same and believe you on all of that, but I'm leery about taking advice on using it on other cars before its ever been tested on on, actually at rpm and such.

I would, but unfortunately I still haven't found anywhere that has SOLID information on what combinations of clutches/pp's/fw's work with different combinations of tranny's/motors.

Ex:

For m50 family motors with Getrag 260 tranny, you can use the following combinations regarding internals:

1,
m20 clutch
m20 flywheel
m20 pressure plate
m20 throwout bearing

2,
e36 clutch
e36 flywheel
m20 pp
euro 323i e30 t/o bearing
note: if using e36 flywheel, you must use e36 starter. flywheel must match starter.

3,etc etc etc...


Something like that would be EXTREMELY helpful. I read lots of "you can do this" or "that should work" but then you read things like "the reason I know is because I slapped it together and my car rolls up and down the driveway when I push it." Thats not a good enough answer for me. I'd love to know what works best, and what is most perferred. Perhaps it's just me, but it seems difficult to find a solid answer. Maybe I'm looking in the wrong places.

[318isbmw]

I would, but unfortunately I still haven't found anywhere that has SOLID information on what combinations of clutches/pp's/fw's work with different combinations of tranny's/motors.

Ex:

For m50 family motors with Getrag 260 tranny, you can use the following combinations regarding internals:

1,
m20 clutch
m20 flywheel
m20 pressure plate
m20 throwout bearing

2,
e36 clutch
e36 flywheel
m20 pp
euro 323i e30 t/o bearing
note: if using e36 flywheel, you must use e36 starter. flywheel must match starter.

3,etc etc etc...


Something like that would be EXTREMELY helpful. I read lots of "you can do this" or "that should work" but then you read things like "the reason I know is because I slapped it together and my car rolls up and down the driveway when I push it." Thats not a good enough answer for me. I'd love to know what works best, and what is most perferred. Perhaps it's just me, but it seems difficult to find a solid answer. Maybe I'm looking in the wrong places.

I know for a fact that method 1 on your stuff does work. The only stuff I've ever heard of the 323 T/o bearing working w/ is the e30 getrag 240 from the m42. Hope that helps some. I'd look around, cuz I know its been mentioned, but doubt it has its own thread sadly. I'll check around too and see if I can find anything for you.

Edit: only deal about method 1, is you need to shave down the back of the flywheel inorder to make it fit against the m50 pan. Otherwise they will rub. But I have heard of instances where it didn't, and I have heard of people shaving off a hair from the pan to make it work too.

[Mako18]

I would, but unfortunately I still haven't found anywhere that has SOLID information on what combinations of clutches/pp's/fw's work with different combinations of tranny's/motors.

Ex:

For m50 family motors with Getrag 260 tranny, you can use the following combinations regarding internals:

1,
m20 clutch
m20 flywheel
m20 pressure plate
m20 throwout bearing

1 works fine, yes!!

2,
e36 clutch
e36 flywheel
m20 pp
euro 323i e30 t/o bearing
note: if using e36 flywheel, you must use e36 starter. flywheel must match starter.

2. e36 flywheel and m20 pp... no they don't work together I just went through this on my swap. The pins in the flywheel are in a different location, the m20 pins are closer to the bolt holes for the pp and visa versa on the e36 flywheel thus not allowing the mating of this combination of flywheel and pp.

However the e36 clutch and pp can be used on the m50 with a e36 starter... haha thats simple since it comes that way dar dar dar. I am not sure while using this combo on a 260 trans if it will clear the bellhousing on the 260? and you would use the m20 t/o bearing. I don't know if the e36 to/bearing could be used?

Its simple the pp and flywheel must match that part is easy, the clutch disks center spline needs to match the trannys shaft spline that you plan to use. for example m20 disk with 260, m50 disk with 250. I am not sure if the spline pattern is the same on the 250/260.

The clutch disk also needs to be the same diameter (actually bit smaller only about 1/8 inch maybe 1/16) as your pressure plate & flywheels friction surface. I believe most bmw e30,e34,e36,z3,m3,m5 disks are all the same diameter. not 100% on this yet.

Starter needs to match the flywheel. done & simple!!

t/o bearing should match the tranny. unless someone can confirm the use of a m20 t/o on a 250 or e36 t/o on 260..? I would still keep this the way its ment to be.

My opinion screw the dual mass e36 hunk of garbage. free up some hp.

I will find out soon if the e36 disk likes the jb flywheel but before any serious abuse its getting the sprung 6 puck.