3 Identical wilwood master cylinders, instructions say I should have a 5/8"?

[jemorgan3]

Hi, while preparing my M/C's for installation, I noticed the instructions say I should have 3/4" AND a 5/8" master cylinders for the brakes... I have 3 3/4 inch M/C's.. two for the brakes and one for the clutch. Am I supposed to have one 5/8" M/C for the rear braking system??

James

[Jeff Kleiner]

3/4” for both front and rear brakes; 13/16” for clutch.

Jeff

[Lugnut Mark]

How do I tell the difference between the 2 sizes … is one bore diameter larger than the other… and can I tell just by looking ? I already installed my pedal box and cannot remember any differences in m/c sizes… I have a coupe I don’t know if that makes a difference or not

[LSX]

Here’s mine. Hopefully this is correct?

223148

[Dgc333]

How do I tell the difference between the 2 sizes … is one bore diameter larger than the other… and can I tell just by looking ? I already installed my pedal box and cannot remember any differences in m/c sizes… I have a coupe I don’t know if that makes a difference or not

They are marked on the body of the mc.

[Lugnut Mark]

All 3 of mine are marked as 3/4 2 for front and rear brakes and one for hydraulic clutch …. Hopefully I have the right setup

[TXeverydayDad]

When I ordered the hydraulic clutch as part of my kit, all 3 supplied mc’s were 3/4”. I just bought a 13/16” for the clutch and am keeping the last 3/4 as a spare. The clutch works with 3/4 as well, it’ll just be a bit more effort.

[jemorgan3]

The coupe instruction manual says the 5/8th's is for the rear, 3/4 for the front and 3/4 is generally the recommended size for the T56 Magnum with an LS motor. Im guessing FF updated the manual brake setup to have two 3/4" master cylinders without updating the instructions. My packing list references all 3 as being 3/4" as well.

[JsMoose]

I have 3 identical 3/4" M/C's as well... just hoping for the best. I imagine the main difference will be pedal-feel. The P/N and part description are labled on my boxes if that helps:
223172

I have to ask the dumb (but related) question. I can skip the "clutch quadrant" steps if using an hydraulic clutch, correct? The M/C just attaches straight to this adapter on the top of the clutch pedal, I believe. If anyone can substantiate this, I would appreciate it just seems to make sense to me.
223173

Thank you!
Jay

[RoadRacer]

Yes ignore quadrant instructions

[Papa]

My kit came with three 3/4" master cylinders as well. Should I be swapping out the clutch now while I have easy access? Not sure what FFR will provide for the slave cylinder as I haven't ordered my engine package yet. Is there a "magic" combination that is recommended? I don't mind swapping out parts for those that are known to work better.

[TXeverydayDad]

My kit came with three 3/4" master cylinders as well. Should I be swapping out the clutch now while I have easy access? Not sure what FFR will provide for the slave cylinder as I haven't ordered my engine package yet. Is there a "magic" combination that is recommended? I don't mind swapping out parts for those that are known to work better.

Yes, there is a magic combination, but as always, it depends on your entire set-up: which clutch and slave cylinder/HRB you’ll use. Tilton HRB recommends 13/16 for their throw out bearing with 1.0-1.1” mc stroke with an 11” diaphragm-type clutch and it feels just right in my leg when driving.

[Papa]

Yes, there is a magic combination, but as always, it depends on your entire set-up: which clutch and slave cylinder/HRB you’ll use. Tilton HRB recommends 13/16 for their throw out bearing with 1.0-1.1” mc stroke with an 11” diaphragm-type clutch and it feels just right in my leg when driving.

Thank you. Since I know zero about setting up a hydraulic clutch, I guess I need to start getting smart.

[Jeff Kleiner]

Forte recommends 13/16" master when using his external slave setup. I have a customer with a Blueprint Windsor 427 and TKX with a HRB. He wasn't getting enough throw with a 3/4" master; it works beautifully after changing to a 13/16".

Jeff