I need to get a new clutch slave cylinder, since all I have on hand is clean housing with no guts. No idea where the one from the donor car went. I found I can get the stock or "long throw" version at bpnorthwest.com.

https://www.bpnorthwest.com/clutch-slave-cylinder-long-throw-tr3-to-tr4a-gt6.html

Anyone use something like this ? Their description indicates you need to get the stock one really down to get the clutch to release.

---

Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

Deleted.



Edited 1 time(s). Last edit at 2019-02-04 01:01 AM by Tonyfixit.

John,
I have never had a problem with the stock slave cylinder's throw length. I would be reluctant to use a long throw cylinder because it might put too much strain on the diaphragm spring in the clutch pressure plate assembly. I have had problems with the diaphragm spring cracking, but I think that may have been on Quinton-Hazel clutches, not the greatest brand.
All the best,
Paul

It all sounds a bit like a bad "band-aid" fix, either for a problem that really doesn't exist or one where the true problem should be addressed rather than applying a questionable workaround? Similar to the dreaded external rocker arm oil feed, etc.

Just my opinion....

---

http://www.fairpoint.net/~herald948/database/

I will go along with Paul Mugford's comment, that the long-throw slave could put additional pressure on the springs. But also, if a long-throw slave is necessary to allow the clutch to release, it could be because the thrust washers in the engine are either too far gone or are missing completely, in which case you are buying into some very expensive trouble.

Go for the normal , the fast acting is for racing , the time it takes to push down the pedal and release the pedal can be reduced by "fast acting" , on the down side some control is given up in exchange for speed . A nice long pedal stroke makes for a pleasant driving . A short stroke is great for a hair faster than the next guy / car .

The operating 'throw' of the slave with each pedal depression depends on the ratio of master cylinder piston area to slave cylinder piston area.
Our clutch systems are hydraulically self adjusting.
Within the total possible physical travel, the 'idle' or 'foot off the pedal' position of the slave piston changes over time as the clutch disk wears,
and the release position changes to establish the free travel.
So fitting a 'longer throw' slave cylinder to a properly fitted and operating yields zero performance improvement.

From the BPNW site, the extended throw cylinder is intended to mitigate issues when the clutch system

It asks: What are the symptoms of a bad clutch slave cylinder?

Given, I have never driven a Triumph, I had no idea if the issue described in the description was even a thing or not. Since all the parts going on the car will be as good as new, I don't suppose I will need the fancy one.

---

Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

John
Get the stock slave cylinder which is a 1" bore.

As I recall the long throw slave is a 7/8" bore which gives it the longer stroke. I've never seen a properly functioning clutch in a GT6 ever require this.

GH

Spitbits only shows the "County" brand that looks to be stamped 7/8. I guess I'll check another source.

---

Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

I'm not fond of the County Brand. I actually like the Moss "House Brand" Classic Gold, had far fewer issues with them. Classic Gold is Taiwan and I believe County has there's made in India.

The 1" bore is what your car came with stock but the 7/8" will work just fine. Doubtful it would have enough throw to somehow cause issues with the pressure plate fingers.

GH

BPNorthwest has a 1" bore version.

---

Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

I put the 7/8" bore unit in my 73 from BPNW and it works fine. Was having trouble with my clutch releasing enough to keep from grinding going into reverse at times (like the motor was not totally isolated from the tranny). It seemed to help a bit but I think my clutch disc (put in 10 years ago and barely driven) must have been a bit too thick. As I continue to drive it things are getting better-probably due to the disc wearing in. The thrust washers on my crankshaft are in good shape. I don't think it could be considered a quicker acting clutch as mentioned above, just more travel at the slave cylinder end.

Hi John: the real solution to this problem is to get a longer plunger rod on the master. Over the years I have seen all sorts of rod designs on the slave and all you do is suceed in pushing the piston further into the slave. Adding a rod 1/4 inch longer will push more fluid to slave and result in more throw on clutch. I have lots of used rods, piece that attaches to the clutch pedal. Feel free to contact me. Just joined but same user name on Porsche forum and ebay. Tons of parts. Wear in pin slot of the plunfer will also take away from the throw geometry. Thanks Rob.