Re bored Girling slave cylinder

[Warren]

My local pals Rick J. and Mike M. we're doing a 5 speed conversion. I was visit and watching their work in progress. I was limping about and told them my clutch was aggravating my knee.
I described it as a heavy diaphragm clutch. With the small scale between Mike's foot and the pedal it read a shocking 40 plus pounds.

The fix involved boring the Girling booster to fit a 1" piston from a 20 dollar MG slave cylinder from Moss motors. Now it's like a 20 lb clutch and happy knee happy me...

Although I have no 5 speed I do have a tolerable clutch. Thanks guys.

 

[Hoghead]

I once had a far too stiff Weber clutch that would flex the firewall using a lot younger knee

 

[sandy]

Wait, so you put a larger master in and the clutch got easier? Or was this on the slave side?

 

[HolyCat]

Wait, so you put a larger master in and the clutch got easier? Or was this on the slave side?

According to the title of Warren's post, it was his slave cylinder that was rebored and got the larger piston.

 

[66TigerMK1A]

Centerforce clutch users don't have that heavy pedal issue... I've had to do 2 rebuild on the slave but switched to DOT 5 when I did the clutch 12 years ago and both are still alive and well...
P.S. no hangup on the 6k rpm 1-2 shift either

 

[michael-king]

Mine has the king cobra 10.5" clutch and pp .. Heavy AF.... 😰

 

[Warren]

Jim , 66TigerMK1A
Centerforce II pressure plates. with throw out and discs. In other words BF stupidly heavy diaphragm clutch. I don't drag race the car. Plus burnouts are discouraged and aren't fast on the autocross course. But they are more fun in a rental car or one that you don't have to fix.

Sandy, when I first heard of the idea it struck me as different as we are used to hearing replacing brake booster and going to a 3/4 brake master.


CTF 360048 is the pressure plate in the car. I gave the invoice to Dan W. who's lightening the load in the cars he plays with. So I don't have the donor slave bracket part number.

 

[66TigerMK1A]

Jim , 66TigerMK1A
Centerforce II pressure plates. with throw out and discs. In other words BF stupidly heavy diaphragm clutch. I don't drag race the car. Plus burnouts are discouraged and aren't fast on the autocross course. But they are more fun in a rental car or one that you don't have to fix.

I’m not really sure ( as usual) what you’re on about but I have a Centerforce ‘dual friction’ and pedal pressure is no more than a Supra…I don’t drag race but do wind it up occasionally and don’t do burnouts as my $$ ‘wide’’ 14” tires are hard to replace. Autocross?? No comment

 

[sandy]

According to the title of Warren's post, it was his slave cylinder that was rebored and got the larger piston.

My bad, my brain saw master not slave. Makes perfect sense.

 

[spmdr]

Back in the mid'90s, Tom Sakai bought some of Tom Patton's used race parts,

among them was a 8" Dual disc, DUAL diaphragm clutch and light weight flywheel.

I'm here to tell you, THAT clutch, with the standard Tiger hydraulics, is the HARDEST clutch

peddle I have ever put a Foot on!!

It is SO HARD, I had Tom give it the FOOT while I looked at the 2 bolt Alloy clutch Slave cylinder

Bracket, to see how bad it flexed!

In spite of how rigid some may think that bracket is, It flexes!


From that point on, I have been temped to change the clutch slave cylinder bore size BIGGER

But it was just yet another thing that would be nice to do, but didn't get done, YET!


I was party to Warren's BIG BORE clutch SLAVE cylinder change and it's a VERY GOOD thing!!

HOWEVER, it MAY not be GOOD in every clutch application!

IF your clutch engages near the floor, you may NOT be able to Disengage the clutch.

...With the Bigger bore.

DW

 

[66TigerMK1A]

HOWEVER, it MAY not be GOOD in every clutch application!

IF your clutch engages near the floor, you may NOT be able to Disengage the clutch.

...With the Bigger bore.

DW

Makes sense…bigger volume of fluid to move = less ‘stroke’
My first Lakewood/6 bolt swap in the ‘70’s for some reason had limited stroke…it was a fine line between being able to release the clutch or have it slip. I think I only had about 2 turns of the adjusting nut to have one or the other. 😱

 

[sandy]

Back in the mid'90s, Tom Sakai bought some of Tom Patton's used race parts,

among them was a 8" Dual disc, DUAL diaphragm clutch and light weight flywheel.

I'm here to tell you, THAT clutch, with the standard Tiger hydraulics, is the HARDEST clutch

peddle I have ever put a Foot on!!

It is SO HARD, I had Tom give it the FOOT while I looked at the 2 bolt Alloy clutch Slave cylinder

Bracket, to see how bad it flexed!

In spite of how rigid some may think that bracket is, It flexes!


From that point on, I have been temped to change the clutch slave cylinder bore size BIGGER

But it was just yet another thing that would be nice to do, but didn't get done, YET!


I was party to Warren's BIG BORE clutch SLAVE cylinder change and it's a VERY GOOD thing!!

HOWEVER, it MAY not be GOOD in every clutch application!

IF your clutch engages near the floor, you may NOT be able to Disengage the clutch.

...With the Bigger bore.

DW

I run a 2 disc 7.25" tilton on my Mustang and it is nice except for the on off nature. Not at all recommend for street. I had looked at some McLeod street twin for a while but figured overkill. My experiences with centerfoce are mixed. Do not really like weights spinning around at high rpm. Just me being paranoid 😀

 

[Warren]

Dan gets some thanks too.

The engagement needs a little clevis rod adjustment but that'll wait.

I've had heavy clutches in my big bore VWs but then I was fit. Cables stretched and busted often now it's me that busts.

 

[Tiger]

As with many of our modifications, beefy clutch assy's push the limits of the original design. Regarding the flexing of firewalls and brackets.... take that as a heads up called metal fatigue. Eventually, this flex may lead to cracking. I've seen it happen, fortunately not on a Tiger.

 

[IvaTiger]

As with many of our modifications, beefy clutch assy's push the limits of the original design. Regarding the flexing of firewalls and brackets.... take that as a heads up called metal fatigue. Eventually, this flex may lead to cracking. I've seen it happen, fortunately not on a Tiger.

Tigers get arthritis when they get old and fatigued