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I want to convert to manual brakes. I have seen the master cylinder kits that Ed Quay and Burkhart offer, but it seems expensive. Can someone give me some dimensions? I would like to know the thickness of the adapter and bolt pattern, and the location of the m/c on the adapter. Can some one help me out?
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Can't help you out with the Ed Quay setup...but check the link in my sig...will show what I done to convert to manual brakes....for reinforcement I used some scrap .8mm stainless that I came up with.
I just called Strange, they asked my brake set up, and sent me out one of their manual M/C. 1 1/16" bore. My biggest thing when converting to manual i wanted them to feel like pwr brakes, i knew after racing a few friends cars with manual brakes it was possible, and thankfully i got what i wanted, full braking effort is only a few toes away
once i got their kit i just took some sheetmetal and welded up the old holes, drilled my new ones, used the strange plate they send with the M/C for the template for the holes, found center of brake pedal, and installed. PITA getting up under the dash with the roll bar installed, but took the front seat out and it made it tolerable. I did have to get a different end to put on the rod that goes into the piston, remove brake pedal assembly and drilled a new mounting hole 1 1/8" higher than the factory pwr attachment point. Very straight forward once you get the thing in hand and figure out whatcha gotta do. Nice thing with the put together kits is it's all there already so no trips into town to make it work, but i've got $120 into converting mine and 3 hours in the garage total, so it's way cheaper if you can do some fab work even when you figure your time is worth something which it is.
The biggest reason for manual brakes is clearance room inside the engine compartment. The booster itself weighs very little. If you have a camshaft that doesn't produce enough vacuum, a vacuum reservoir can also be used.
I use a master cylinder from an S10 that had manual brakes. I have no idea what the bore size is but it works for me. I didn't use an adapter but simply drilled new holes through the firewall and inner support bracket to center the booster in the hole. You can't simply attach the master cylinder to sheet metal. Pushing the brake pedal will force the master and break the sheet metal. That's normally why an adapter is used. The master attaches to the adapter with it's 2 bolts. The adapter then uses the factory 4 bolts to attach to the body. The adapter can be any thickness since a new pushrod needs to be fabricated to make up the difference. An aluminum plate at least 1/2" thick would be minimum. 3/4" or 1" would be better.
As mentioned above, the pushrod needs to be relocated on the brake pedal. Power brakes has the pushrod pushing upwards. The manual master cylinder needs the rod to push straight into it. 70's GM cars had a provision on the brake pedal for manual or power brakes. The pushrod simply relocated up 1" on the pedal to push straight and also to give a mechanical advantage required for manual brakes.
Since late model cars never come with manual brakes, that option is now gone and you need to fabricate a way to attach the pushrod in the new location. Because there also isn't a brake booster, a new, shorter pushrod needs to be fabricated. I cut my old pushrod down and rethreaded it to accept a 3/8 rod end which I attached to the brake pedal.
You'll also notice that the third gen master cylinder is probably the only one that has the brake lines coming off it on the engine side instead of towards the fender like just about every other master cylinder. You'll need to reroute or replace the brake lines so they'll go to the other side of the master cylinder. The aluminum master cylinders use metric bubble flare fittings.
__________________
87 IROC-Z
All engine, no power adders! Bests: 9.348@144.71
Mine works okay, but I wish I didn't need to push the pedal as hard. I'm planning on doing disk upgrades all the way around from the stock disk/drum to LS1 if not C5.
The pushrod should push as straight as possible into the master cylinder. If the angle is off, it will cause premature wear to the piston and bore. For a drag car, that could be a lifetime but if it ever starts to wear, there's always a chance of the piston getting cocked in the bore.
Mine works okay, but I wish I didn't need to push the pedal as hard. I'm planning on doing disk upgrades all the way around from the stock disk/drum to LS1 if not C5.
That's why there was absolutely no way i was going to use OEM anything, i hear guys online talk about use this M/C from this yr and style of car all the time, i've driven/raced a number of cars that have gone this route, and not one has a brake feel nor performance anywhere near an aftermarket set up. After i raced a older couples 66 rustang that had a strange M/C i knew that's who i was going to call, their stuff was touchey, you fart and the dang things wanted to lock up, almost like the brakes in the newer sports cars. Granted their entire set up was all aftermarket, but the way mine is now:
GM metric calipers front/rear
NO proportioning valve...you want better brakes than what you have, dump that POS, even in factory form like when i first gutted mine, the brakes were soooo much stronger it was'nt funny, so i just eliminated it all together since we have more rubber out back then in the front you need a stronger rear biased anyhow, so the 50/50 works just fine.
Strange 1.03...bore manual M/C
factory sized hardlines
braided steel lines from body mounts to calipers
full braking is accomplished with the tip of your toes and light pressure, just like a power brakes set up
That be the girl, i went down and bought a rod end that screwed onto the rod that connects your brake pedal and goes into the piston. drilled a hole in the brake pedal arm, installed a long shoulder bolt through the rod end, through the pedal arm and then locknut and locktighted a nut on the long part of the bolt as a secondary measure to make sure it never came apart.
It's not pretty but I didn't make a show car. You can see the master cylinder mount bolts going through the support bracket. 3/8" rod end using a grade 8 bolt and a stover nut. The pin below the rod end is the factory mount position for the pushrod.
I have a strange manual master cylinder and relocated the bolt hole 1" higher and it's no where near factory feel on the brakes. Have to push HARD to get it to engage.
__________________ my car thats never done
"I'd rather be judged by 12 than carried by 6"
First Place Camaro Modified Thirdgenfest '05, Second Place Camaro Modified Thirdgenfest '06, Best Modified Camaro Thirdgenfest '07 , Second Place Camaro Modified Thirdgenfest '08
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I have a strange manual master cylinder and relocated the bolt hole 1" higher and it's no where near factory feel on the brakes. Have to push HARD to get it to engage.
What size piston did you go with? sounds like too large if pedal pressure it hard, if they're set up right, you should not to have actually exert any physical effort into it at all, should be no different than getting into your daily driver and touchig the brakes.
I'm not sure it was a kit that I purchased that had a 4th gen f-body adapter bracket made for the firewall out of aluminum which also fit my 3rd gen perfectly. I "thought" it was the 1 1/16" bore size, but I could be wrong. Either way I bled the brakes with a vacuum pump and gravity bled them and they're still rock hard.
I'm not sure it was a kit that I purchased that had a 4th gen f-body adapter bracket made for the firewall out of aluminum which also fit my 3rd gen perfectly. I "thought" it was the 1 1/16" bore size, but I could be wrong. Either way I bled the brakes with a vacuum pump and gravity bled them and they're still rock hard.
Did you prime the M/C before putting on the car? a freind of mine had alot of trouble getting all the air out of his system recently too. He bought a kit for his 78 malibu all his internet buddies talked up and spent 3 nights bleeding the things before it finally came around, and his were rock hard too just like they were with his power brakes and no vacuum. i know he "said" he bench bled it, and said he went through 3 of the big brake fluid bottles of fluid before they came around. He initally gravity bled them, and then went into the old way of buddy pumping pedal, and cracking the lines...but 3 nights of bleeding and 98oz of fluid...something was definately not right.
yes I bench bled it for quite a while. Then hooked up the lines and ran 4 bottles of brake fluid through it thinking that would help but it didn't since the vacuum bleeder didn't have air bubbles in it at all either.
That be the girl, i went down and bought a rod end that screwed onto the rod that connects your brake pedal and goes into the piston. drilled a hole in the brake pedal arm, installed a long shoulder bolt through the rod end, through the pedal arm and then locknut and locktighted a nut on the long part of the bolt as a secondary measure to make sure it never came apart.
What thread is the pushrod? Looks like fine thread.
I finally ordered my Strange Engineering M/C. I have a question. Is drilling a new hole further up the brake pedal (for the pushrod) really the best position? It seems like the pushrod is getting pushed upward instead of forward. Here are a few pictures. The last picture shows where I think the pushrod should connect, or maybe further back. Any thoughts? BTW. The pushrod thread is 3/8 24.
That pedal doesn't look like it's back all the way. You can see in my picture, the pedal is almost vertical putting the pushrod end directly under the pedal pivot.
That pedal doesn't look like it's back all the way. You can see in my picture, the pedal is almost vertical putting the pushrod end directly under the pedal pivot.
I see, but you removed the brake light switch to get the pedal back further. This will be street car too and I need the brake light switch.
I just called Strange, they asked my brake set up, and sent me out one of their manual M/C. 1 1/16" bore. My biggest thing when converting to manual i wanted them to feel like pwr brakes, i knew after racing a few friends cars with manual brakes it was possible, and thankfully i got what i wanted, full braking effort is only a few toes away
once i got their kit i just took some sheetmetal and welded up the old holes, drilled my new ones, used the strange plate they send with the M/C for the template for the holes, found center of brake pedal, and installed. PITA getting up under the dash with the roll bar installed, but took the front seat out and it made it tolerable. I did have to get a different end to put on the rod that goes into the piston, remove brake pedal assembly and drilled a new mounting hole 1 1/8" higher than the factory pwr attachment point. Very straight forward once you get the thing in hand and figure out whatcha gotta do. Nice thing with the put together kits is it's all there already so no trips into town to make it work, but i've got $120 into converting mine and 3 hours in the garage total, so it's way cheaper if you can do some fab work even when you figure your time is worth something which it is.
what part # is the MC from strange?
i am with everyone else, ive never seen a 3rd or 4th gen act like it has power brakes after completing the swap.
i very much want to get more holding power on the starting line, as my stock booster is not up to the task. i just dont want to deal with a hard pedal driving around.
I haven't given up on this project. I had to wait to get my car back to make any progress. Anyway... I made some progress. I machined a spacer/adapter out of some aluminum that I ordered. Right now it is 1 inch thick. I may mill it down some later. Here is some pictures.
nice looking spacer, definately machine it down some. I know saving half that thickness for underhood and valve cover/valve lashing jobs does'nt sound like much, but it's huge once it's all assembled and in place Looks great.
Ok I hate to keep beating this dead horse but after searching forever i still have questions. When I first did the swap it was in a hurry and rigged. I was using the big bore strange mc and the pedal was like a rock! I have no prop valve and seemed as if the rear drums (which suck) were doing all the work. I got a small bore mc now and i just cant find a fitting for the front port to run to my factory 1/4 brake line to the drums! Why does it seem everyone else has 3/16 line for front and rear? I have fittings to run 3/16 front and rear but not the bigger 1/4. The front port is for the rear brakes correct. Do i need the 1/4 to the rear? Do i need a prop valve? If so i should it be on the rear or front or both? What would happen if i went down to the 3/16? Any help would be great. If yall need pics let me know.This is all thats holding me up!
__________________ 91 bird 383 11:1 cr victor jr heads super victor intake crane(nitrous) solid roller 252/260 .630.630 875 bill mitchell prepped holley stahl 1 7/8 primary to 3 1/2 collectors. turbo action built th350 jw(nitrous) 8" 4200 stall pst3.5"driveshaft factory 10 bolt w/ 3.73s mickey thompson 325/50/15 radials best pass so far 11.52@117.87
alot of you guys got some nice setups, just wanted to say that.
i have manual breaks on mine and all i did was removed the mounting bracket from back of the booster and bolted back on the firewall and centered the master cylinder to the hole in the firewall were the push rod comes thru. drilled new holes and bolted it up.
and as far as the length of the push rod i just unhooked it from the pedal and placed it into the master cylinder and cut out what i didn't need and welded it back together. i also drilled a new hole in the pedal about 3/8 inch higher than the original hole to correct the leverage.
the only thing about it is i could use a better master cylinder to have better brake pedal feel but other than that the car stops without any great effort.
but what you got started is on the right track, and i have to say that the machine work is pretty sweet.
Thanks for the compliments. I ended up milling the spacer/adapter down half thickness to .500". I have it installed and the fit is great. When I installed everything the pedal was to close to the driver. I heated up the pedal and made it straighter to get it back where it belongs. This kept the pushrod geometry correct. I hope it all works! I'll try to get some photos soon.
SuperT - That is how we did my dad's car years ago.
Thanks for the compliments. I ended up milling the spacer/adapter down half thickness to .500". I have it installed and the fit is great. When I installed everything the pedal was to close to the driver. I heated up the pedal and made it straighter to get it back where it belongs. This kept the pushrod geometry correct. I hope it all works! I'll try to get some photos soon.
SuperT - That is how we did my dad's car years ago.
well the idea to do my brakes that way came from my uncle who has been bracket racing for 30+ years, so it is probably the old school way and i can't say i have to many complaints considering he helped me get my car to run 11.76 @ 114.7 with an all iron 355sbc.
by the way my box is from a '87 4 banger s10, called autozoned with the part number and thats what they said i had.
Last edited by superT; 03-11-2009 at 12:42 AM.
Reason: promised info
__________________ my car thats never done
"I'd rather be judged by 12 than carried by 6"
First Place Camaro Modified Thirdgenfest '05, Second Place Camaro Modified Thirdgenfest '06, Best Modified Camaro Thirdgenfest '07 , Second Place Camaro Modified Thirdgenfest '08
MFBA March 2008 Featured Calendar Vehicle
Ok so i got the lines done yesterday and tried it and my pedal is rediculous hard! I started w the big bore strange unit and now using an Oreilly's unit and both have been the same. How do I know that the master cylinder is bled? Why would air in the master make the pedal hard? Its like im pushing hard and not getting any pressure to the corners.. This race is creeping up on me and still not ready.
mine is rediculous hard as well. did you relocated the pushrod hole 1" higher on the pedal? I did that during the install and it's still like stepping up a cliff.
__________________ my car thats never done
"I'd rather be judged by 12 than carried by 6"
First Place Camaro Modified Thirdgenfest '05, Second Place Camaro Modified Thirdgenfest '06, Best Modified Camaro Thirdgenfest '07 , Second Place Camaro Modified Thirdgenfest '08
MFBA March 2008 Featured Calendar Vehicle
im not positive. i was told by someone at racecraft that this particular mc should be the smaller bore but if i have to ill buy the other strange mc so itll work. do I need a prop valve? will air in the mc cause a hard pedal? seems backweards.
__________________ 91 bird 383 11:1 cr victor jr heads super victor intake crane(nitrous) solid roller 252/260 .630.630 875 bill mitchell prepped holley stahl 1 7/8 primary to 3 1/2 collectors. turbo action built th350 jw(nitrous) 8" 4200 stall pst3.5"driveshaft factory 10 bolt w/ 3.73s mickey thompson 325/50/15 radials best pass so far 11.52@117.87
im not positive. i was told by someone at racecraft that this particular mc should be the smaller bore but if i have to ill buy the other strange mc so itll work. do I need a prop valve? will air in the mc cause a hard pedal? seems backweards.
Air in the lines "should" cause spongey pedal not rock hard. I know with my Strange MC with the 1.0313" bore i have no issues and the pedal feels like a power brake unit, easy travel and good brakes. My connecting point is roughly 1 1/8" higher on the brake pedal than the stock mounting location.
I "have" a aftermarket proportioning valve, but i have it turned wide open so there is no bias going on, my rear tires have more contract patch than the front so having it split 50/50 is probably better anyhow...i know it gets that way when running larger rear tires and skinney fronts (such as pro street type apps)
Check piston size for sure. Too large of a piston you have high peda effort and minimal braking pressure since your pushing such a large volume of fluid you cant build the psi you need to actuate the brake calipers. Go with too small of a piston you get a high line psi to actuate calipers but are'nt pushing enough fluid volume to get full braking in one push of the pedal so you'd need to pump it a few times to get fluid built up in the lines to exert full force braking...it's a fine line to walk with manual brakes, but it can be done. I've driven other cars with manuals that felt like power brakes, and mine feel this way as well...or else i would'nt let my wife and buddies drive it.
For those that have to push the pedal too hard here is some of the probable causes
According to a book I have
1: Master Cylinder Too Large
2: Insufficient Pedal Ratio
3: Inadequate Caliper Piston Area
4: Oil Or Grease On Brake Linings
5: Frozen Pistons In Caliper
6: Fade From Improper Brake Lining Compound For Application
I run a run a stock s10 master cylinder that has a front bore of 1.417 and rear .945 bore with 4 piston front disc and single piston rear disc and the car stops very well with what i have
ok so if the bore is too big then what if i added 4 piston calipers on just the front and reused the stock drums out back? would that change anything? I have single pistons now.
__________________ 91 bird 383 11:1 cr victor jr heads super victor intake crane(nitrous) solid roller 252/260 .630.630 875 bill mitchell prepped holley stahl 1 7/8 primary to 3 1/2 collectors. turbo action built th350 jw(nitrous) 8" 4200 stall pst3.5"driveshaft factory 10 bolt w/ 3.73s mickey thompson 325/50/15 radials best pass so far 11.52@117.87
u me and the tree!!!
