Jump to content
HybridZ
zcarnut

A One Inch Diameter Brake Master Cylinder for the S30 Z Cars

Recommended Posts

^ I just came to post a similar question. I have one on order just as a stock replacement for now. I planned on doing the Toyota brake upgrade right away, but I don't think funds will allow for it until winter, so it will be pumping the stock front disks and rear drums on my 77. I assume it will make for a pretty stiff pedal, but I was just confirming that I should remove the front check valve and leave the rear.

Share this post


Link to post
Share on other sites

I installed a 1" Wilwood MC 2 years ago in combination with vented Toyota front calipers (S12 not S12W, same piston sizes as the solid rotor Toyota caliper but configured for vented rotors) and Maxima rear calipers and didn't remove the check valves. I've had absolutely no problems with any brakes dragging or the system being weak. I'm also running a 280Z booster (not the 280ZX) so there is a bit more pedal effort required but it helps with modulating the brakes at the limit so I prefer it this way.

 

I also took a different approach to the 10mm thread issue, I fabbed completely new lines with the 3/8" fittings on one end and 10mm fittings on the other, these connect to the splitter block/brake pressure switch mounted to the frame rail. I also eliminated the stock proportioning valve in favor of an adjustable one on the rear brake circuit, I personally think this change is manditory when replacing the rear drums with disks.

 

A couple things I ran into when I swapped to the Wilwood 1" MC.

1. One of the bleeders was completely crushed right out of the box, I replaced both of the cheap aluminum ones with the brass ones from my stock MC.

2. One of the check valves was totally mangled right out of the box. I replaced this with one from my stock MC which had 2 installed.

 

The symptom of the mangled check valve was it wouldn't let any fluid pass in either direction. I found this while trying to bleed the rear brakes and not getting any fluid at the calipers.

Share this post


Link to post
Share on other sites

I installed a 1" Wilwood MC 2 years ago in combination with vented Toyota front calipers (S12 not S12W, same piston sizes as the solid rotor Toyota caliper but configured for vented rotors) and Maxima rear calipers and didn't remove the check valves. I've had absolutely no problems with any brakes dragging or the system being weak. I'm also running a 280Z booster (not the 280ZX) so there is a bit more pedal effort required but it helps with modulating the brakes at the limit so I prefer it this way.

 

I also took a different approach to the 10mm thread issue, I fabbed completely new lines with the 3/8" fittings on one end and 10mm fittings on the other, these connect to the splitter block/brake pressure switch mounted to the frame rail. I also eliminated the stock proportioning valve in favor of an adjustable one on the rear brake circuit, I personally think this change is manditory when replacing the rear drums with disks.

 

A couple things I ran into when I swapped to the Wilwood 1" MC.

1. One of the bleeders was completely crushed right out of the box, I replaced both of the cheap aluminum ones with the brass ones from my stock MC.

2. One of the check valves was totally mangled right out of the box. I replaced this with one from my stock MC which had 2 installed.

 

The symptom of the mangled check valve was it wouldn't let any fluid pass in either direction. I found this while trying to bleed the rear brakes and not getting any fluid at the calipers.

 

 

Just to be clear, you left the check valves in the front and rear outlets?

Share this post


Link to post
Share on other sites

That is consistant with my experience with the 280ZX MC. I had no drag problems with the 280ZX MC which had check valves in the front and rear outlet ports. With the 280ZX MC the brakes were high and firm. The check valves are the only variable I haven't addressed.

 

 

Looks like the check valve issue has come up before: http://forums.hybrid...eck-valves-f-r/

Edited by Miles

Share this post


Link to post
Share on other sites

Miles, did you reinstall the check valves into your wilwood? Keep us inform. I am doing my install tomorrow and would hate to take off the mc again to reinstall the check valves if I have crappy pedal feel. I am in my 3rd mc. 2 of the 15/16 280zx and now going wilwood 1" mc. 15/16 are just not holding pressure for me for some reason even rebuild units from local auto parts stores.

Share this post


Link to post
Share on other sites

Yep, both are in place and have caused no problems.

Same here - I left both check valves in place - works fine - I have Toyota calipers and vented rotors in the front and the 240sx calipers with 300zx rotors in the rear. Also used the 10 inch 280z 2+2 booster. I made custom lines with the different threads on both sides... easy!

Edited by kj280z

Share this post


Link to post
Share on other sites

Miles, did you reinstall the check valves into your wilwood? Keep us inform. I am doing my install tomorrow and would hate to take off the mc again to reinstall the check valves if I have crappy pedal feel. I am in my 3rd mc. 2 of the 15/16 280zx and now going wilwood 1" mc. 15/16 are just not holding pressure for me for some reason even rebuild units from local auto parts stores.

 

I plan on reinstalling the check valves this weekend. I'll post the results later.

Share this post


Link to post
Share on other sites

Forgot to mention my flare ends are pretty much doomed now and leaking so I will have to replace that soon as it has a very minor leak. I am considering reinstalling the check valves from the 280zx mc since they look identical and my wilwood only came with rear check valve.

Share this post


Link to post
Share on other sites

Just a quick little note to anyone thinking about doing this. The "plugs" as they call them/outlet fittings for the MC that were referred to in the original post are no longer available through courtesy parts. Or anywhere else that I called. So like most people have done posting on this it is probably easiest to make new lines with 3/8's fittings one end and 10 mm on the other to make this work. Only costs an extra 10 bucks total. I will be finishing this hopefully this weekend! Thanks a lot!

Share this post


Link to post
Share on other sites

Just a quick little note to anyone thinking about doing this. The "plugs" as they call them/outlet fittings for the MC that were referred to in the original post are no longer available through courtesy parts. Or anywhere else that I called. So like most people have done posting on this it is probably easiest to make new lines with 3/8's fittings one end and 10 mm on the other to make this work. Only costs an extra 10 bucks total. I will be finishing this hopefully this weekend! Thanks a lot!

 

 

You don't need to do that. Remove the outlet port fittings from the Wilwood 1 inch MC and replace them with outlet port fittings from a 72-78 240Z/280Z or a 79-81 280ZX. This will provide the 10mm connection to the hardlines. In my case I removed those fittings from the 1979 280ZX MC that had failed in my 240Z and installed them in the Wilwood MC. Keeps it simple.

 

 

Also, see post 3 above.

 

 

Other info: My 280ZX MC had check valves in the front and rear outlet ports. I moved them over to the Wilwood MC outlet ports. My brakes don't drag.

Edited by Miles

Share this post


Link to post
Share on other sites

You don't need to do that. Remove the outlet port fittings from the Wilwood 1 inch MC and replace them with outlet port fittings from a 240Z/280Z/280ZX. This will provide the 10mm connection to the hardlines. In my case I removed those fittings from the 280ZX MC that had failed in my 240Z and installed them in the Wilwood MC. Keeps it simple.

 

 

Also, see post 3 above.

 

 

Other info: My 280ZX MC had check valves in the front and rear outlet ports. I moved them over to the Wilwood MC outlet ports. My brakes don't drag.

 

 

Hmm, according to the original post that not all the outlet fittings from every single car will fit into the wilwood MC. I have also found this to be true, first with my 240z's MC fittings being totally different. And then again with my 280z's MC fittings which looks to be an aftermarket replacement. So I'm not sure where you are coming from when you say any S30/S130 MC outlet fittings will fit. And as for the check valves are concerned I plan on leaving the factory Wilwood's in and seeing how it goes.

 

Plus one of my fittings was rounded from previous owner repairs so it just made sense to me to do it this way.

 

Just sharing what I ran into for anyone else who might be interested in doing the swap...

Share this post


Link to post
Share on other sites

Hmm, according to the original post that not all the outlet fittings from every single car will fit into the wilwood MC. I have also found this to be true, first with my 240z's MC fittings being totally different. And then again with my 280z's MC fittings which looks to be an aftermarket replacement. So I'm not sure where you are coming from when you say any S30/S130 MC outlet fittings will fit. And as for the check valves are concerned I plan on leaving the factory Wilwood's in and seeing how it goes.

 

Plus one of my fittings was rounded from previous owner repairs so it just made sense to me to do it this way.

 

Just sharing what I ran into for anyone else who might be interested in doing the swap...

 

 

Yes per the original post the fittings from a 71 240Z will not interchange with the Wilwood MC. I corrected my post to show that the 72-78 MC fittings are interchangable as well as fittings from the 79-81 280ZX MC (the fittings I used).

 

Thanks for pointing that out.

Share this post


Link to post
Share on other sites

The fittings will fit from the 15/16 master cylinder to the wilwood! I almost want to say and z fittings will fit into the wilwood master cylinder for f and r lines. I did not reinstall my check valves and left them off. After a few miles driving my brake pedal is now stiffer and feels great! Weird but I guess minor bubbles made its way out or up? Who knows, it feels great now minus check valves.

Share this post


Link to post
Share on other sites

The push rod length must be adjusted. If it is too short you will have a long pedal that grabs near the bottom of its' travel. If the the push rod is too long, it will not allow the piston in the MC to return to the position where fluid can flow back into the MC. This will cause your brakes to lock up after a few stops. Adjusting the pedal inside the car will not help.

Edited by Miles

Share this post


Link to post
Share on other sites

The push rod length must be adjusted. If it is too short you will have a long pedal that grabs near the bottom of its' travel. If the the push rod is too long, it will not allow the piston in the MC to return to the position where fluid can flow back into the MC. This will cause your brakes to lock up after a few stops. Adjusting the pedal inside the car will not help.

 

My push rod is not adjustable for some odd reason and it's about 4mm too short. I'm thinking about taking the spacer between the master cylinder and the booster and have it milled to make up the difference. I would replace the booster but it's brand new and I had it powder coated already. Any other ideas would be greatly appreciated.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...