Clutch Qustions

[mphmotorwerks]

If I was going to replace my clutch, Could i replace a M3 clutch on a 318ti tranny or must I have a M3 tranny in my ti??

[FATHER]

i think the clutch disc fit but the pressure plate not, i'm not 100% sure

[L84THSKY]

You can put an M5 clutch in.

Originally Posted by mphmotorwerks

If I was going to replace my clutch, Could i replace a M3 clutch on a 318ti tranny or must I have a M3 tranny in my ti??

[FATHER]

wath is the diferences between the 3 cluths??

[L84THSKY]

All I know is the lightweight flywheel I bought was recommended to mate with the M5 clutch, all works well together.

Originally Posted by FATHER

wath is the diferences between the 3 cluths??

[mphmotorwerks]

does it offer any type of performance upgrade.

[L84THSKY]

The only upgrade a clutch can provide is better clamping force. I can drop the clutch and smoke the tires.........BOTH tires......LSD

Originally Posted by mphmotorwerks

does it offer any type of performance upgrade.

[mphmotorwerks]

well....yeah I understand that but is it better to install a m5 clutch vs a upgraded 318ti clutch

[mooseheadm5]

IMO the M5 clutch is WAAAY overkill for a 318ti. The clamping force is high, sure, but the pedal effort is too. A 325 clutch can hold all the power the ti will ever make, and an M3 clutch can hold even more. If you put a heavier clutch in, you can lighten the pedal effort with an M3 slave cylinder.
Whatever you use you have to have a matching clutch and flywheel. 318 is 215mm, 325 is 228mm and M3 and M5 are 240mm. Note that the M3 and M5 are the same diameter, but the M5 is designed to hold loads more HP/TQ. This is done with more spring pressure. Overcoming this requires more pedal effort.
-Paul

[L84THSKY]

Originally Posted by mooseheadm5

If you put a heavier clutch in, you can lighten the pedal effort with an M3 slave cylinder.

Been there done that

Originally Posted by mooseheadm5

This is done with more spring pressure.

I think that is why they recommend the M5 clutch. The higher spring pressure/design, reduces chatter of the LTW flywheel when idling.

[mooseheadm5]

Originally Posted by L84THSKY

Been there done that



I think that is why they recommend the M5 clutch. The higher spring pressure/design, reduces chatter of the LTW flywheel when idling.

The spring pressure I was referring to is the diaphragm spring that holds the pressure plate to the disk. Don't think the flywheel should ever chatter when the car is idling clutch engaged or disengaged. In fact when dual mass flywheels chatter it usually means that you need a new one. They recommend an M5 clutch because psychos that put LTW flywheels on their cars tend to be the kind of people that sidestep the clutch for smokey burnouts.
That, and the clutch disk has the necessary damping springs to be used with a single mass flywheel (dual mass flywheels are internally damped so the clutch disk has no springs on it as the flywheel takes up the driveline lash.)

Weights listed below are from ETK shipping weight. In my experience, the flywheel will weigh less than quoted shipping weight.
Stock E36 ti twin mass flywheel: 215mm friction surface, ~27lbs!
E30 318i (M10) single mass flywheel: ~14lbs (but is 215mm)
Below are single mass 228mm flywheels
E30 325e flywheel (up to 5/86): ~23.6lbs
E30 325i flywheel: ~18.5lbs (depends upon year)
1982 528e flywheel: (drumroll) ~13.5 lbs (realoem says $350 for a new one)
If you insist on 240mm flywheel:
533/633/733 (up to 1/84) + M5/M6 flywheel: ~16.5 lbs
but I have no idea if it will fit the motor (it probably will not, I'll check monday.)
Remember, you'd have to get the matching clutch kit. Also, a single mass flywheel may be thinner than your dual mass, so your clutch slave pushrod must be lengthened TWICE the difference in thickness between the new and original flywheel for the clutch to work properly. IMO, it is worth the effort for the money saved. New or used single mass flywheel + new clutch costs less than LTW flywheel alone and though it is heavier, there is less of a tradeoff when driving your car on the street. My boss put an 82 528e flywheel on his E30 327i and it revs fast and leaves my indentically prepped(actually mine is more heavily ported) 327i behind. My M50 325ti will probably get an E30 325i single mass to make it rev faster but harder for wifey to stall on hills (flywheels store energy...) My M50 E30 325i supercharged will get the 13.5lb flywheel for sure. Trust me, the 228mm flywheels and stock clutches hold 200hp easily even though mine is over 250,000 miles old, and I am not easy on it (I tow up to 1200lbs with my car!)
Any other questions?
-Paul