Clutch pedal height

CR67rep · #1 (**permalink**) 06-02-2018, 12:13 AM

Those who are running hydraulic clutches.... I am attempting to set up my new hydraulic system and I'm running into a problem with the clutch pedal being substantially higher than the brake. I spaced the clutch master cylinder off the firewall but now the pedal bottoms out before the clutch disengages. Do I need to modify my pedal box or pedal to make the heights correct?

DanEC · #2 (**permalink**) 06-02-2018, 04:36 AM

You would need to provide more information on your pedal box set up and maybe some pictures of it to get a good answer. Is this a slave cylinder or hydraulic TO bearing set up?

Ron61 · #3 (**permalink**) 06-02-2018, 06:41 AM

I agree with what Dan said. And do you have any adjustment for the travel of the pedal? I have seen two ways that people fixed this but without seeing your setup I am hesitant to mention either of them.

Ron

CR67rep · #4 (**permalink**) 06-02-2018, 09:43 PM

As far as I can tell its the "factory" CR pedal box looking at build manual it's done up the same. Using Tilton 75 series master and Tilton 6000 series release bearing. Pedal currently has adjustment using nut on front and back of pedal connection.

Gaz64 · #5 (**permalink**) 06-03-2018, 02:55 AM

As other have said, photos please, but your master cylinder to slave ratio is not high enough. The master needs to bigger, or the slave smaller.

Also a brand new clutch might be a little "furry" and not fully disengage.
Needs to be run-in a bit.

Gary

DanEC · #6 (**permalink**) 06-03-2018, 04:44 AM

Quote:

Originally Posted by Gaz64

Also a brand new clutch might be a little "furry" and not fully disengage.
Needs to be run-in a bit.

Gary

That's the best description I heard of this phenomenon, but it's true. I've noticed on two recent clutch jobs that after a few miles the engagement point in the pedal travel has come up from the floor and engagement travel overall decreased.

CR67rep · #7 (**permalink**) 06-03-2018, 06:27 AM

I'll get some pics today, clutch itself actually has about 7k miles on it. The master is matched per specs by Tilton to the release bearing. I changed the hydraulic system as it was an older build and I changed the bellhousing to get rid of the 17 degree tilt (SBC originally using Camaro T5 bell).

CR67rep · #8 (**permalink**) 06-03-2018, 06:42 AM

Already had the pedal box out, if pics are need with it in I can hang it.

patrickt · #9 (**permalink**) 06-03-2018, 07:20 AM

If you find you need more pedal adjustment, like me, try using a 7/8" bore Tilton master cylinder -- that makes quite a bit of difference on an ERA car and is relatively cheap and easy.

CR67rep · #10 (**permalink**) 06-03-2018, 09:30 AM

Currently using 13/16 bore Tilton based off the guide referencing release bearing and clutch size. Unfortunately time is not my friend right now as I'm supposed to be heading to Power Tour on Friday.

Gaz64 · #11 (**permalink**) 06-03-2018, 04:05 PM

Sounds like a step-up from 13/16 to 7/8 should sort it.

CR67rep · #12 (**permalink**) 06-03-2018, 06:08 PM

Thanks for the info all. I'll likely deal with the higher pedal for now until I have time to step up to a 7/8 bore.

Ron61 · #13 (**permalink**) 06-04-2018, 03:20 AM

For a short term fix could you put a thicker pad on the brake pedal to make it more even with the clutch pedal? I know this isn't a good fix to keep but if you aren't doing any heel/toe braking and shifting it might make it feel more normal when driving.

Ron

tortuga · #14 (**permalink**) 06-05-2018, 06:27 AM

Do you have an adjustable rod between the slave and the clutch fork? If not it's simple to Make one out of some all thread (used ~5/8 I think) and a nylock nut: just cut a piece of all thread, nicely round it where it goes into the slave and then use the nylock (round nylon side to fork) to adjust out slack with slave bottomed out leaving about 1/8" slop. To do this I put a clamp on the slave between the back of the slave and the end of the rod to LIGHTLY seat the slave piston, then loosen the nut while holding the rod with vice grips away from where the nut runs until the fork has about 1/8" of "rattle".
Cured similar woes in my SPF...

CR67rep · #15 (**permalink**) 06-05-2018, 07:26 AM

Tortuga, I'm running a hydraulic release bearing so there's no adjustment point or shift fork at the trans end.

tortuga · #16 (**permalink**) 06-05-2018, 07:23 PM

Quote:

Originally Posted by CR67rep

Tortuga, I'm running a hydraulic release bearing so there's no adjustment point or shift fork at the trans end.

Got it didn't catch that all important fact...good luck with it.

MaSnaka · #17 (**permalink**) 06-05-2018, 08:44 PM

I put threads on the end of the rod for my brakes and made it adjustable. Not hard to do but I know you want the brake pedal slightly out front of the clutch. Also looks like your brake pedal ratio in the pedal box is set up for power brakes not manual. I have a pic of the mods I made to my pedal for the manual ratio in my gallery.

Good luck
John

CR67rep · #18 (**permalink**) 06-07-2018, 09:29 AM

I'm running power brakes with 7" dual diaphragm booster and corvette style master cylinder. I've got the pedals set up satisfactorily for now, slightly higher than I'd really like but they work safely