There are something like 3-4 different arms for the 915 of different eras. The earlier ones had just a plain as as you've possibly got and the later gear boxes had the springs which are used as an assistance to reduce the pedal effort required to get the arm moving.

....i am speaking my thoughts here so please chime in with any of your thoughts.
I am running the saco slave AND MC. My gearbox has the same TOB release set up as the one pictured - with the omega spring.

Ive set my clutch pedal up to have 2mm of freeplay on the push rod - same as the brake MC. My pedal wont return all the way back (obviously as there is no return spring)


now......standard beetle has a return spring on the clutch release lever arm.

Am i right in thinking the porsche set up has a return spring on the pedal cluster?
I understand that the porsche box has the omega spring as a 'helper' spring but this seems to work the other way.

I am thinking i should probably try and do something similar? I just dont like the fact that my pedal doesnt return fully.

Imho, its not about the pedal not returning, but your fluid is not returning for some reason. Or your master pedal rod IS returning and just not connected to your pedal arm in the same way that it is releasing. Hope that makes some sense to you?
So, what exactly is not returning besides the pedal itself? This should help trace the problem.

I'am still running the same original SACO master cylinder since... I think 6 years now and counting.

The pedal returns back to a point ( clutch isnt slipping) but then it doesnt "snap" back like you would get with a cable operated clutch with a return spring on the lever arm (which is why i mentioned the return spring on the porsche pedal cluster)

I gues the best way to see if the fluid is returning would be to crack the bleed nipple and see if fluid comes out under pressure.

Wally is your MC the mk1 cast version or the billet ally one out of interest?

Cast or billet alloy? Hmm, I really wouldn;t know tbh, its been too long since I peaked into the tunnel.
Mine was the old set which still had the nylon tube to connect the slave to the master. I replaced it with copper brake line and was afraid the brake inner diameter would be too small, but it isn't.

I think maybe you just don't need or want the free play in the pedal? So the slave needs to be engaged somewhat at all times? My return comes purely from the pressure plate pushing the slave back after releasing. No further springs at all (besides the spring inside the slave I now remember...). I think thats what I meant by my last post.
Hope that helps some and you get it sorted mate.

Sounds like maybe i am worrying too much as my pedal return is purely down to the pressure plate also. Maybe i'l adjust up the slave a little more to bring the biting point a little higher therefore bringing the pedal back up higher when released.

Having not worked with this set up in the past it's difficult to know how it should be - thanks for sharing your experience with it.

Deano

So what size master did we end up thinking worked out the best?
19mm= 0.748 or would a little smaller provide a little softer pedal with better snap back. Would 17.75mm=0.700 have enough volume for say a Sachs sport clutch, IE stiff sob?