135 replies to this topic

[Lc69]

Thankyou, much appreciated

[Lc69]

So after scratching my head for a while, trying to work out if I really need to remove the pedal......I thought I’d remove the rubber stop to see how much travel I could steel......

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So it looks like I could fit a different stop and get the travel I need without modifying the pedal.

[S pack]

email sent Tony.

[S pack]

Get a sharp knife and trim the rubber stop down to about 4mm thick?

[Lc69]

Email received, thankyou
I cut it down to 3mm.....about 2mm too short ha ha
I’ll get another and go again.
I think I still might need to increase the hook, but I’ll try it as is without the stop installed

[toryman76]

Hey Tony. I was under the car today giving the clutch a bit of a minor adjustment as it was getting a bit sticky in gears last drive. After readjusting it I measured the fork travel in the bellhousing window to be 40mm exactly as you had established. Interesting though I measured the other dimensions you gave relative to your sketch and I calculated I should have 168mm pedal travel which is exactly what the instructions suggest. (A=290 B=69 D=40) My pedal sits just shy of the brake pedal and it measured 163mm after adjusting. Mind you I didn't play around with the ball as it was just a quick adjustment at the cable so I can go cruising next week.

I’m going through the same pain at the moment......and just found your thread, which is helping a lot.
I haven’t checked the 48mm dimension for the fork adjustment yet, but I would say I am close based on your photos.
Can I ask, How far does the fork actually travel in the bellhousing slot when you full press down the clutch pedal?
Apart from being interested in the fork position, I guess I’m curious to know how much cable pull is required.
The reason I ask is because I’ve done exactly the same thing, New Delrow fork and bearing, similar fork adjustment, and the clutch is not disengaging.
I believe the pedal has the wrong leverage ratio and is also possibly short on travel.
I currently have 60mm from the pedal pivot to the hook on the pedal, and around 110mm under the pedal which provides around 25mm of cable pull.
It looks like I need something like 40mm to disengage the clutch......but it would be really helpful if you could confirm.
I’m currently using a std 4cly pedal (LC), which i was told would work, but I’m guessing for 6cyl not 8cly.
(I’m running 253 with M20)

[Lc69]

Thankyou again, it’s always good to double check these things.
163mm travel would give you almost 39mm, so there’s not much in it.
I’ve seen similar numbers quoted now, so it feels like the stars are aligning.

I have more than 40mm of travel available at the fork now, so I’m reasonably confident with the ball, bearing, fork setup.
I can trim the rubber stop to achieve 170-175mm of pedal travel, still with some buffer, and a good pedal height.
I’m in the process of 3D printing a new hook for the pedal, extending it to 65mm from the pivot.
These changes should give me 40mm of cable travel.
Not strong enough to test for real, but should be ok for s dummy test.

Then I just need to adjust the length of the cable entry at the firewall to make sure the adjustment is in the right position.

Once I’m happy that all this is going to work I will get the new hook made in steel and test everything properly.

I will keep everyone posted. Thanks again for confirming these dimensions.

Hey Tony. I was under the car today giving the clutch a bit of a minor adjustment as it was getting a bit sticky in gears last drive. After readjusting it I measured the fork travel in the bellhousing window to be 40mm exactly as you had established. Interesting though I measured the other dimensions you gave relative to your sketch and I calculated I should have 168mm pedal travel which is exactly what the instructions suggest. (A=290 B=69 D=40) My pedal sits just shy of the brake pedal and it measured 163mm after adjusting. Mind you I didn't play around with the ball as it was just a quick adjustment at the cable so I can go cruising next week.

[toryman76]

Good one Tony. Great to keep a document of the information that works which is why I kept updating this thread along the way.

I reckon I might need to tweak the ball position a little to get the pedal height up but for now I will test drive and if it's ok I'll leave it till next service.

[Lc69]

Bit of an update....
I have fitted a new stop trimmed down to 5mm thick.
This still gives a good buffer and provides 165mm under the pedal.

After a few revisions I have settled on a pedal extension of 10mm, so a hook that is 70mm from the pivot.
By moving the hook towards the firewall a little I will not need to change the cable exit on the firewall.
The pedal extension will be a steel block, fastened by the bolt in the end of the pedal, with a hook that takes a std HZ 6cyl cable.
I have 3D printed a version of the extension and tested the cable pull.

I need to shorten the cable entry on the firewall by about 8mm to allow for the extra cable pull required at the clutch fork.
I will show a pic of that soon.

So the pedal ratio is 280/70 = 4 (very close to a HZ pedal, hopefully not too heavy)
Cable pull = 165/4 = 41mm

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[Lc69]

Latest update. I drove the car on Australia Day with the changes mentioned nd everything worked well.
I plan to document the setup at some stage for anyone else that needs to do this in future.

In summary....
Cable travel required to disengage clutch is around 40mm (Ensure you have the correct thrust bearing and the fork is adjusted to allow this much travel)
The pedal ratio should be around 4 - 4.6 based on the various configurations I’ve seen. (Larger the ratio, lighter the pedal)
So...Travel under foot, divided by ration, needs to give you around 40mm of cable pull.

Thanks to everyone that helped with info.
It seems so simple now, but without your help I would of still been fumbling around using trial and error.

[S pack]

Top stuff Tony . Uncanny as I was thinking about your dilemma today and wondering if you had had any success.