Subaru hydraulic clutch time..., Need help from the gurus! Options

[Chris H.]

Hey all,

I'm at the point where the hydraulic clutch setup needs to be mapped out for my Subie conversion. The donor trans is from a 2006 WRX with a 13/16 slave cylinder. Initial reaction is to buy a 13/16 generic (wildwood or CNC) master cylinder so they match and give a “factory” clutch feel but after some internet searches it seems that pedal travel is also a factor and might mean a different size would be better. I’ve seen some GREAT hydraulic clutch threads but could not find one for the Subie trans setup.

I’d assume the pedal throw is probably similar but could be wrong. BIGKAT is using a 3/4 and mentioned he might rather have a 5/8. His trans likely has a ¾ slave.

Any insight or thoughts on this? You don't have to be right! Brainstorming is great too. (IMG:style_emoticons/default/biggrin.gif)

[Mike Bellis]

Matching the existing size is the rule of thumb.

If you had a 3/4 slave and push it with a 5/8, it would take longer throw of the pedal for full motion of the slave.

If you have a 5/8 slave and push it with 3/4, it would take less throw of the pedal.

This doesn't take into account of pedal force (foot pressure) that it take to push the larger master.

The good news is that Wilwood masters are cheap. Around $50. So you could experiment without breaking the bank.