Bigger Master Cylinder, Ideas? Options

[Bigmeanbulldog55]

Well, since I've done some stuff to my car the stock clutch doesn't want to hold right anymore. It still holds, but it won't if once I finish. So, as a preventative measure, I want a bigger master cylinder to disengage my stage 3 clutch. I had it in for awhile, but the stock master cylinder wouldn't open it enough to switch gears super smooth. So I took it out and put a stock back in. Now I want it us it, but I have to get something to make it work. So, for you gear heads, what can I do? How can I increase pressure to the slave cylinder and make this clutch work. This might be a nice brake upgrade too. Let me know guys. If no one has any ideas, I'll just go yank one off a Tacoma and see how close it is.

[Bitter]

i dont see how a bigger clutch master cylinder would help your brakes any, same name but 2 different parts dude.

im sure with a little fabrication work a larger diameter or longer stroke master cylinder would work. preferably a larger diameter to move more fluid and keep a stock or near stock stroke length.

[Bigmeanbulldog55]

i dont see how a bigger clutch master cylinder would help your brakes any, same name but 2 different parts dude.

im sure with a little fabrication work a larger diameter or longer stroke master cylinder would work. preferably a larger diameter to move more fluid and keep a stock or near stock stroke length.

Are you kidding me? I could have sworn that it was just one unit for the 2 things. Dang it, I need to pay more attention when I'm tearing my motor apart. Were the heck is the clutch master cylinder? I don't get how if I would hit the brake alot without a good bit of revs, the clutch wouldn't work as well. Maybe I'll do them both anyway. I guess I'll ask my uncle what he thinks I should do. Obviously I'm not ready to take this on my self. I feel like a real tard.

[Bitter]

the clutch master cylinder should be next to the brake master cylinder. yea, you do press in the brake and clutch at similar times but theyre not the same part.

http://toyotacelicaonline.com/atomconv/2.9.jpg
http://www.clutch-parts.com/images/product...00046311asc.jpg
i know its a small pic, but do you see that cap next to the brake booster and below the wiper motor? thats the clutch master cylinder.

also, DO NOT swap brake master cylinders from other cars, the bore and stroke isnt matched to your brake system and it can be very dangerous.

This post has been edited by Bitter: Sep 24, 2006 - 1:05 AM

[Bigmeanbulldog55]

I just went out and checked it. That's for the pic man. It was actually a little low on fluid. Not much at all though. Doesn't hold that much either though. I topped it off and the brake fuild. Do you think I could use that DOT4 stuff and get a little boost? Other than that, should I just get a master cylinder and boar it out like I would a motor and put a bigger piston in there?

[Bitter]

well....
brake fluid designations just indicate the boiling point of the fluid, since the slave cylinder doesnt get hot it wouldnt matter at all what kind of brake fluid you put in the clutch system.

boring out the master isnt a good idea, you'd have a hell of a time finding pistons, springs, and rods to fit it, and the inside has a special finish which is very hard to reproduce.

[Bigmeanbulldog55]

So what should I do then?

[Bitter]

make sure that your current system is working properly
or
adapt a larger master/slave cylinder from another vehicle, or just try a larger master and see how that works out.

[Bigmeanbulldog55]

lol. Well, glad to see we're getting somewere. That is pretty much the idea I started with. I'll see what I can find on the order of larger equiptment.

[Bitter]

you've tried adjusting the clutch pedal height? was the pedal bottoming out before the clutch was completely released? i assume you've bled the system
or was it just too hard to push the pedal all the way down with the stiffer pressure plate springs?

[Bigmeanbulldog55]

you've tried adjusting the clutch pedal height? was the pedal bottoming out before the clutch was completely released? i assume you've bled the system
or was it just too hard to push the pedal all the way down with the stiffer pressure plate springs?

Yeah, I bled the system already. The pedal would bottem before the clutch was fully released. Pushing it down wasn't a problem. I messed with the adjustment on the pedal, but I would get it so high that it wouldn't grab right, or low that it wouldn't release.

[Bitter]

sounds like either your master or slave cylinder is bad, theres little seals in them on the pistons. over time those seals harden and leak or they get flipped over the wrong way (its a cup seal the expands with fluid pressure to make a tighter seal with higher pressures)

[playr158]

honestly i doubt trying to ghetto rig up a new bigger master cylinder will do anything for you...there are cars with much higher demands and modifications that are using the exact same one without any issues...
you probably have an issue somewhere with a clutch fork, or seals that need to be fixed thats causing your problems.....

[Bigmeanbulldog55]

sounds like either your master or slave cylinder is bad, theres little seals in them on the pistons. over time those seals harden and leak or they get flipped over the wrong way (its a cup seal the expands with fluid pressure to make a tighter seal with higher pressures)

I've checked on the price of these. They aren't every expensive. I just thought if it was bad, or going bad, it would have gotten worse. Seems to be maintaining pretty well. I'll keep an eye on it. If it gets worse, I know what I'll get. If I need to put that clutch in, I'll try buying those and installing them before I try custom stuff.