Confirmation of Clutch Master Cylinder Bore Size Needed.

[Guest nwzeeman]

Ready to replace my Datsun clutch master cylinder on my 1978 280Z to work the T5 5-speed behind my 350 SBC. Searching the archives, it appears that most have bumped up the bore size from the .750 (3/4") listed in the JTR book to a .875 (7/8") bore size. I see several new Tilton and Wilwood versions of master cylinders on Ebay and wanted some feedback from you guys before I purchase. This is not going to a racer Z, just a solid driver. I'm looking at the .875 bore master cylinders with the 1.1" (Tilton) or 1.2" (Wilwood) stroke and the plastic reservoir. I understand going to anything over a 1" bore size would put a lot of strain on the firewall.

 

Any pro/cons of bore size and/or brand would be apprecieated.

 

For reference the Wilwood master cylinder I'm thinking I need is on page 2 of the PDF file link:

http://catalogs.wilwood.com/_pdf/_tech/MasterCylindersFluidsandControls.pdf

 

Thanks. -Rod

[Dan Juday]

I have a f-body WC T5 in my car. I'm using the Tilton 7/8" master cyclinder. Works great. I tried like crazy to get the 3/4" one to work but no dice.

 

Also, I did the drill and tap thing on the slave. I haven't had any problems in the three to four years I've been driving it but I would recommend using an adapter instead. A buddy here on the site made it for me when I did the swap on a friends car. If you ever have to replace the slave it's now a bolt-in.

[Zerrari GTO]

Dan- is the adapter you mentioned something currently available or is it something that must be fabricated?

 

If so, are there any plans, diagrams for it?

 

Thanks!

[wheelman]

I was able to get a Wilwood 3/4" master to work but I had to cut the pedal stop off the floor to get enough travel. If I had it to do over I'd use the 7/8" instead, the 3/4" has a very long throw before the clutch disengages which makes for a slow shift.

 

Wheelman

[Guest nwzeeman]

Thanks for the feedback guys...looks like the 7/8" bore is the way to go. I too did the drill and tap on the slave cylinder.

 

On a side note....my slave cylinder was missing the bleed screw...anybody know the thread size on the T5 slave cylinder bleed screw? I'm thinking of just plugging it and putting in a 'T' just above the input port on the slave and putting a universal bleed screw there. -Rod

[Dan Juday]

Dan- is the adapter you mentioned something currently available or is it something that must be fabricated?

 

If so' date=' are there any plans, diagrams for it?

 

Thanks![/quote']

 

I noticed on Ron Tylers old web site that he made one for himself for the tranny swap on his Vette. I e-mailed him and he turned one for me for what I thought was a very reasonable price. $35.

 

Since then others have contacted him about making more but he was too busy with other things at that time. You could ring him up and see if he'd make you one.

[Guest 73LT1Z]

I just installed a Wilwood .875" clutch master I bought from Summit Racing for $66. This is the MC you referenced.

 

Here is the trick to installing it in a 280Z (copied from my Wilwood brake MC thread):

The clutch pin on the pedal is big time aggravating. I was able to swap out the rod in the Wilwood clutch MC with the Datsun one, so I didn't have to rethread or shorten anything. The clutch rod was an easy swap for anyone else doing this- pop the retaining clip out on the Datsun unit, remove the rod (leave the retainer). On the Wilwood one, remove the snap ring, replace the rod with the Datsun one & use the Wilwood retainer & snap ring. This stuff interchanges so easy it is like it is made by the same company!

 

It fits like factory, same mounting hole spacing, same nuts to hold it in place= NO FABRICATION (for a change ).

 

You also need an adapter for the end if you are running other than a -3AN fitting.

[Guest timmy72240]

bro i am running a t5 with a willwood master 1 inch with a custom made braided hose that pins in to the plastic t5 slave problem solved ....