Will a concentric slave cylinder give a lighter pedal?

[Triggsy]

Hi,

I have an AP Racing uprated clutch in my BMW M70 / Audi 01E transaxle combo in my Diablo replica. Naturally this has resulted in a pedal just that bit harder than i'd like - i can live with it (done 2500 miles with it so far) but would prefer a lighter pedal if possible.

I currently have a 0.625 master cylinder and this gives the perfect bite point. I did initially have a 3/4" master cylinder but that was even harder. The engine and gearbox are currently apart while i have been refreshing the engine so if i'm going to do anything about it now is the time.

I know that the Mondeo and Saab CSC's are popular fitments and i think they would fit in the available space but the question is will it make a difference? I've found loads of comments on the web that concentric slave cylinders result in a lighter pedal but is it that noticeable going from an external to internal slave cylinder?

Thanks
Simon

[robbocop33]

From what i generally read people say cable clutches tend to be lighter than hydraulic, never heard many people noting differences though between internal and external hydraulic slaves, if there is a noticeable difference it'll probably be due to some obscure internal design difference if it makes it lighter.
I've got an rs225 megane with an internal slave cylinder, and it's the stiffest clutch i've ever driven!

[Happy Jim]

It will only make things lighter if the bore changes size compared to the original slave. You could also try changing the clutch pedal ratio (change the pivot point to give more leverage & travel will make it feel lighter).

Rgds

Jim

[Steve_D]

Or fit a remote servo.

Steve

[Triggsy]

Thanks for the replies.

I've tried different pivot points but it always ends up as a compromise between bite point and firmness.

I did look into remote servo's last year but wasn't sure if it was the right solution. However i notice a thread in the TVR section has been updated with good results so i think i'll go down that route, probably with the MGB unit.

Thanks
Simon

[stevieturbo]

If all the leverage ratios are the same ( whether mechanical or hydraulic )...then pedal effort will be the same for cover pressure etc

[Triggsy]

Just to update, i've bought a Powertune 1.9 ratio remote brake servo. Will fit it over the next couple of weeks and hopefully it will do the job.

I'll report back.

Cheers