Rotary Car Club - View Single Post - Help me upgrade clutches in my REPU, rotary GLC and FB

Jeff20B · 10-18-2008, 03:15 PM

Quite.

It's update time! My bro's red '84 FB got one of the RB flywheels, a 225mm HD disc and a centerforce 215mm pressure plate. The pedal effort is easy and apparently grips harder as RPMs rise. It's a new clutch disc that needs time to break in so I haven't tried to feel whether the pressure plate indeed grips harder as RPMs go up, or whether it's just a gimmick. The engine is a 12A so it doesn't necessarily need super grip anyway. It matches the character of the car nicely ie it has power steering, awesome brakes, comfortable seats, nice exhaust note. Basically nothing is extreme on this car, and I couldn't be happier with the way it turned out for him. Note there is a 5mm extra lip of clutch material that extends beyond the friction surface of the pressure plate. No problems.

The GLC is getting a new engine as the one I had built for it had the wrong apex side pieces (the little triangle things) from '74-'75 seals and get damaged tips from a little bit of missing chrome on the rotor housings. The engine will get rebuilt with excellent chrome rotor housings, new correct apex side pieces and an older RB light steel flywheel, already broken in 225mm stock disc and a stock 215mm pressure plate. Stock is more than adequate in this small, light car. Infact the pedal effort is greater in this car compared to a 1st gen 7 due to the pedal being shorter with less travel. Stock feels almost like street strip. I don't forsee any problems with having a 5mm lip as described above.

The blue FB got an old aluminum flywheel with a ferrous friction surface of 225mm but already worn by a 215mm disc. I had an old used 225mm HD disc (7.5mm thickness) and a 215mm street strip pressure plate. I tried this combination and it works quite well. The pdeal effort is high as the spring fingers in the diaphram are shorter than a comparable 225mm SS pressure plate, but thankfully the FB has a long clutch pedal so bumper to bumper driving is acceptable, although tiring. I would not want anything stronger, and thankfully, it is not required at this time. I have plans for increasing the power, as will be chronicled elsewhere on this site, but for now with a supercharger, I haven't noticed any slippage. Again there is a 5mm lip of disc that extends beyond the pressure plate. Everything seems fine.

There you have it. Several clutch jobs with a mismatch of 215mm and 225mm parts.

10-18-2008, 03:15 PM	#12
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	Quite. It's update time! My bro's red '84 FB got one of the RB flywheels, a 225mm HD disc and a centerforce 215mm pressure plate. The pedal effort is easy and apparently grips harder as RPMs rise. It's a new clutch disc that needs time to break in so I haven't tried to feel whether the pressure plate indeed grips harder as RPMs go up, or whether it's just a gimmick. The engine is a 12A so it doesn't necessarily need super grip anyway. It matches the character of the car nicely ie it has power steering, awesome brakes, comfortable seats, nice exhaust note. Basically nothing is extreme on this car, and I couldn't be happier with the way it turned out for him. Note there is a 5mm extra lip of clutch material that extends beyond the friction surface of the pressure plate. No problems. The GLC is getting a new engine as the one I had built for it had the wrong apex side pieces (the little triangle things) from '74-'75 seals and get damaged tips from a little bit of missing chrome on the rotor housings. The engine will get rebuilt with excellent chrome rotor housings, new correct apex side pieces and an older RB light steel flywheel, already broken in 225mm stock disc and a stock 215mm pressure plate. Stock is more than adequate in this small, light car. Infact the pedal effort is greater in this car compared to a 1st gen 7 due to the pedal being shorter with less travel. Stock feels almost like street strip. I don't forsee any problems with having a 5mm lip as described above. The blue FB got an old aluminum flywheel with a ferrous friction surface of 225mm but already worn by a 215mm disc. I had an old used 225mm HD disc (7.5mm thickness) and a 215mm street strip pressure plate. I tried this combination and it works quite well. The pdeal effort is high as the spring fingers in the diaphram are shorter than a comparable 225mm SS pressure plate, but thankfully the FB has a long clutch pedal so bumper to bumper driving is acceptable, although tiring. I would not want anything stronger, and thankfully, it is not required at this time. I have plans for increasing the power, as will be chronicled elsewhere on this site, but for now with a supercharger, I haven't noticed any slippage. Again there is a 5mm lip of disc that extends beyond the pressure plate. Everything seems fine. There you have it. Several clutch jobs with a mismatch of 215mm and 225mm parts. Last edited by Jeff20B; 11-14-2009 at 11:37 PM.