Ok, I did a search and did not find what I was looking for, some stuff helped, but some person left out some valuable info on part#. I am looking to do this so I can free up some room underhood, make it look cleaner, the car will have very limited street use, and I would hate to leave my stopping abilities in the hands of a 12v vacuum pump.

I have read about using a Mopar/Dodge master cylinder when switching over to a manual setup, now which one? from which of the many cars they made? Also what about the S-10 M/C? I know Stephen 87 IROC on the drag board used that, but what about hooking up the pedal? The pics he has on his website show a eyelet hooked to a stock pedal, is that true?? Or am I missing something there. Also what about strengthening the firewall, will a small, let say 3"x3" piece of 3/8" or larger metal work? Or do I need something bigger?? And what about any sort of part numbers, I read a few but those were for the eyelet and bolts and such. And do I need to change the proportioning valve(or which ever one that is hanging below the M/C)? And do I need to change the line lock setup I have currently hooked up? Any more info is greatly appreciated, I want to drag the car out at least once before it snows!!

 

I've wanted to do teh same thing, and this topic has come up a few times in the past few months but nobody posted any information that was incredibly worthwhile. They'd mention a kit, but I had no idea what else was needed. Its hard to research something that isn't incredibly documented.

I just want to free up some room under the hood and drop a few more lbs off. I don't have a stock brake setup though.... 13" C4HD fronts and 12" LS1 rears. Not sure if all the pressures are going to work out the same. It'll be entirely street driven, but I don't mind a stiffer pedal... I like the feel of one.

 

I'll be doing the swap over the winter and have been doing alot of reading/asking for proper set-up to get brakes as good as what I'm used to with my pwr brak set up now.

Parts I will be using is Wilwood high volume aluminum master cylinder Jegs p/n 950-260-6765 $54.99

and Wilwood rotary prop valve Jegs p/n 950-260-8419 $39.99

When going to manual brakes you want a smaller piston bore to create higher pressure in the brake lines, I was thinking about going 3/4" piston bore, but cant get any opions from anybody about that since 7/8" bore seems to be the norm, anything bigger and your pedal will be like a rock.

You will need a firewall brace prior to mounting manual master cylinder, I've seen first hand on our cars what happens when just bolted to the factory sheet metal....alot of flex on the firewall around the master cylinder which takes away from braking force from your foot as well as faituging the metal over time and possibly causing future problems.

You will need to drill a hole in your brake pedal arm 1" higher than the factory hole currently there. There are 2 reasons for this-1. to keep proper rod alignment to keep pushrod into master cylinder as straight and level as possible and 2. the most important factor is more leverage-which means you'll get more line pressure from your efforts pushing the brake pedal since the pivot point has been changed....kinda like adding a extension to your ratchet handle when trying to break a rusty bolt loose...give it more umph so you get better braking with same effort.

Line lock will still plumb the same as it will be run inline prior to front brake line T. Adjustible proportioning valve will be installed inline before it heads to the rear diff. You could mount it inside the cab so you have brake bais control on the fly, or mount it like most do under the hood, once you find the sweet spot you never have to mess with it again.

Over all simple swap and inexpensive, just time consuming, and I'm in the same boat as you, I want/need more under hood clearance, want the option to go as crazy a cam/motor I want wihtout worrying about pwr brakes having enough vacuum or buying a $250 electric pump to insure they work and adding more weight/clutter under the hood, but I want good brakes when I go to use them...

 

so the proportioning valve goes inline in the same area like the line lock except for the rear side of the master cylinder correct?

i want to make sure i get the idea of a proportioning valve, it is in a sense, kind of like a pressure regulator on a fuel system with an electric pump, except it is used in brakes right?

 

U got it

 

That's some of the best information I've read on this swap, thanks a lot IHI. I more than likely won't be doing this until next summer at some point since I'm up here at school now. I already have the Summit prop valve (but not installed) and I'm going to want to buy a line-lock so I can do it all at once. No sense in converting all of this over and making my own lines only to have to re-do them for a line-lock in the future.

As for strengthening the firewall, I'd assume something like 1/4" or even 1/8" steel would work on the driver's side of the firewall, maybe a 6"x6" piece? 3x3 seems kinda small to me, and 3/8" seems like overkill for thickness. More surface area, the better because it'll even the load out on more sheetmetal.

Keep in mind by changing the leverage on the brake pedal, you're going to have to move your foot further down to get the same output effort with the same input effort. I know it is just about required to move it up on the pedal, I'm just saying what the side effect to that is.

Thanks for listing the M/C you'll be using. I'll have to look into that a little bit. I'll post back later with some more thoughts/questions on the idea.

 

When I go to reinforce, I'll use 1/8" something or other in that area, how far out I take the additional plate will depend on what I decide when I do it...one of the off the hip things but that should be plenty of additonal support since it's tied in with the firewall thickness also.

Not sure if i understand what your trying to say about moving your foot down? All you'll be doing is drilling a new hole 1" higher on the brake pedal arm itself and moving the new MC rod to that newer/higher hole....the brake pedal arm itself will still be mounted in the same spot it is now.

 

Oops, should've clarified. I meant your foot will have to travel further as you push down.

 

tie some blocks too your feet....then you can compensate for the distance

 

IHI how does the M/C work with the front brakes if it only has a single outlet?? i am slightly confused on this problem.....any one have any pics?

 

Same as any MC on the market, you run a line out to your line lock, from the outlet of the linelock you run a line to a T and from the T you go to each front caliper.

 

Heres mine : Strange 1 1/8 master with a wilwood prop valve. 1/4 " alum adapter plate , heim joint on the pushrod. I havent tested it yet.

 

1 more

 

hey TA_Drag do you have the part numbers for the components you used?? and have you gotten around to feel how hard the pedal is? curious cause i dont want to have to stand on the pedal to slow down

 

I think a 1 1/8" MC is too big for this kind of setup. 1" probably seems to be best still I think.

 

Is that just a piece you made and bolted it to the firewall, then mounted the M/C onto it? My booster is spaced out from the firewall with some thin looking brackets that are tacked onto the firewall. I need to change my racecar over to manual brakes but not sure on the easiest and cheapest way to do it.

 

I'm using the strange 1 1/8" MC and it does seem too big. I've drilled the pushrod hole up 1" above the stock mounting hole (too stiff) then again about 1 1/2" farther up the brake pedal. It stops well now. The pedal does still seem to be a little stiff and I'll end up making another hole farther up yet before I'm done.

 

does anyone know if there is a difference between the S10/baby blazer manual MC and the full sized Chevy truck MC?? cause i was at the junkyard today snooping around and saw a bunch of fullsize trucks with manual MC, and since it is only like $25 for a used one, what is the difference??

 

ok, heres another noodle scratcher from me....
What about using a 79 Camaro manual master cylinder??
I took a look at my buddies Z28 and he has manual brakes, disc from drum rear, and i figure our cars and a 79 are very similar in weight and stuff. Who thinks there might be a problem with using one?? Cause 14.99 from Advance Auto parts is a HELLUVA lot better than a $100 one from Jegs or Summit. So does anyone see a problem??

ALSO how do you run the push rod correctly?? Does it just sit in the back of the piston in the little dip by pedal tension?? or does it screw in some wheres?? any help is better than wear i am not