Can I use a 225mm flywheel and clutch in a standard 914 side shift tranny?

We're gonna need more information on exactly which flywheel and clutch you have in mind.

The Cap'n

The flywheel is an aluminum Fidanza for a 70-71 911. The clutch would be for the same same year/car. I would imagine I would need the corresponding pressure plate as well?

For a 6 bolt fly why? when a '69 911 fly and a stock /4 PP and clutch works real good and is a bolt on.
Now if you have a 9-bolt fly it's a different story....

There is a reason the Cap'n wanted to know more about your planned set-up, but if it's secret we might not be able to help you.

The flywheel has to bolt up to the crankshaft and the clutch center has to slide on to the input shaft of the transmission. If you have a 2.7 or earlier it's 6 bolts for the flywheel, 3.0 or later is 9 bolts. So the flywheel need to be what your cranks is. The 901 tranny and the 915 tranny input shaft splines are different, so your clutch needs to match that. The pressure plates are either pull or push, you need a push for a 914 setup unless you plan to make a custom cable and throwout fork.

BTW, I have a 215mm 6 bolt (914-6 or early 911) flywheel for sale for the same $150.00 that I paid for it here. It works with a 914 clutch & pressure plate and a 901 tranny.

If you use the 225mm assembly from a '70 - '71 911, the input splines for the friction disk is the same as the /4. Problem is the clutch cover (pressure plate) was the first (and only for two years) is a "pull type". This means the throwout bearing is locked into the fingers and is pulled out rather than pushed in for release. This would require modification of the 914 tranny to be like the '70 - '71 911/901 tranny.

Also, as stated before ... the /4 is 5 bolt attachment and the /6 225mm is 6 bolt. If the flywheel you want to use is for a /6, then you will have to modify it to fit a /4.

BTW, the '70 - '71 only clutch package from Sachs is $800.00

I have a 1970 911 2.0L crank (6 bolts) and a 225mm flywheel. If I understand what has been said in this thread earlier, a 225mm clutch (friction disk) should not be a problem and fit the splines on the 914 tranny. So, as it stands, sounds like the issue preventing me from a complete 225 bolt-in solution is the pressure plate. I would need a 225mm push type pressure plate. Is there such a pressure plate available anywhere?

Sounds like my other option is to go all 215mm and is all bolt in. Are there any performance advantages using a 225mm vs. a 215mm in a 914/6 (used for DE/track)?

Is your flywheel lightened?