So the clutch slave was changed from the McLeod throwout bearing to a standard setup with the fork and pivot stud. Because the fork had to be cut to fit the space between the tranny and the tunnel wall it made a change in the force requried to push the clutch in. It also meant that the travel of the clutch pedal was cut way donw – felt like it was on or off within a 1/2 inch. It worked but was not fun to drive.
My solution was to find a master with a smaller diameter piston. The normal setup is a 3/4″ piston in both the master and the slave. I checked around and found a 5/8″ master. That would mean about a 40% increase in travel needed but also less force. I got the 5/8″ unit I’ll look for the model later and post it, I think it was a Nissan pickup. To mount it I had to drill new holes in the mounting block. Then make a push rod for the piston. The one that came with it was way too long. I grabbed a bolt of the right length and used the grinding wheel to form the head. It worked great. The clutch feels much more like a normal unit. The travel is good and the amount of pressure needed is way donw. I’m happy with it so far. We’ll see how it works out once I drive it a bit and a better feel for things.
Here you can see it in the upper left corner – it’s tilted because the mounts were and there isn’t room to turn it the right way and still fit.
Leon
When you converted from the Mcleod to the external slave, I am assuming that you removed the HTOB, what parts did you use. I am in the same boat and think that this is the way to go. Also, what changes if any did you make to allow you to remove the transmission without removing the engine?
Thanks
Hi- I remove the HTOB. I used a Perfection 39754 Clutch Master Cylinder from Advance Auto parts. If you put “Perfection 39754″ in Google it will bring up a few sources. It’s for a 1989 to 1994 Nissan 240SX. It has the 5/8″ bore vs the 3/4″ that’s normally used. That way you need more travel but less force. Turn’s out it’s not noticable in the pedal once it’s together.
I had to redrill one of the mounting holes in the pedal box where the clutch and brake master cylinders mount. It means the clutch master is tilted a bit but the difference isn’t enough to make a difference. Here’s a pic:
http://leonsmgb.com/wp-content/uploads/2012/01/2011-12-14_13-08-56_830.jpg
ON the bottom I used a pull type slave cylinder I got from Speedwaymotors.com. It has a 7/8″ bore. There’s a model without the fittings on the end, I got the one with the fittings – made it real easy to mount: # 556NP102U. It was $56.99. The banjo fitting made it easy to mount. The clutch fork is available from Speedway also # 91018100, also available at a lot of local parts stores. It’s listed as a GM Standard clutch throwout fork.
The end that the slave cylinder is normally mounted to has to be ground away so it fits between the tranny and car floor. You can see most of it here:
http://leonsmgb.com/wp-content/uploads/2012/01/2011-08-29_15-32-47_483.jpg
The mounts at each end have play – it needs to be able to float a bit because of the change in angles as it’s used.
Here’s a couple more pics:
Clutch fork, throwout and slace-
http://leonsmgb.com/wp-content/uploads/2011/09/2011-08-29_15-38-45_918.jpg
Tranny before it goes in the car with the bracket Terry made for it, also you may have to grind a bit off one of the side of the tranny to get the bracket on –
http://leonsmgb.com/wp-content/uploads/2011/07/DSCN0796.jpg
http://leonsmgb.com/wp-content/uploads/2011/07/DSCN0794.jpg
To remove the tranny – undo the drive shaft and pull it out. Unbolt the cross member (need a tranny support under the tranny) and tilt things down enough to get the bolts out of the bell housing. take the cross member off and slide the tranny out. May have to also disconnect the exhaust.
The clutch works very nice now, a bit heavier than my HHR SS, but not much different than I remmeber my 327 Impala being years ago. Of course “years ago” helps here.
Next time it’s up on a lift I’ll see if I can get a few more pics of the mounts and such.
leon …