I am looking for the bore size of the clutch master cylinder and if possible the clutch pedal ratio.

I ask because I am installing an LNF engine with MU3 transmission into a custom vehicle. (like Ariel Atom). I will be using a Wilwood or Tilton master cylinder with a overhung pedal assembly with a pedal ratio of 6.2:1.

I have searched and cannot find any information about what the bore size is, I have also searched for what the Atom uses and have had no luck thus far.

If anyone has a loose OEM clutch pedal, I assume it can be easily measured to find the pedal ratio. The bore size is not as easy to measure, but any info that someone can help with would be greatly appreciated.

Thanks

 

Maybe I am answering my own question, but I found an image on an Ariel Atom forum of a master cylinder which uses an Ecotec engine, although an LSJ.

Link to image: Pedals and steering column

You can see one of the brake MC it is a 5/8". On the Clutch MC you can barely make out "X"/8. So it could either be 5/8" or 7/8"or 1 1/8".

Looking at the size of the cylinder compared to the brake cylinder, it doesnt appear to be larger, so at this point I am going to assume it is a 5/8".

As a reference, I would still be interested in knowing the original OEM size and pedal ratio if anyone can obtain the information.

Thanks