Finished the scarebird conversion, a few notes.

[DJCarbine]

DJ, since you have the stock clutch linkage, what headers do you use if any?

I use stock manifolds, I am in search of headers that are made to clear the clutch linkage when I do plan to switch over to headers and a performance exhaust.

 

[68conv4sp]

Me too. Options that I have found include replacing the z-bar with the hi-po type which apparently allows tri-ys to be used. Others have suggested shorties but they look like they may hit the engine mount. Good luck.

 

[Stangboy67]

The stock drum distribution block does not have a plunger that I know of, the disc/drum block may have that plunger you described, but I am unsure. I was under the assumption that in even of a line leaking, the dual resevoir master cylinder would keep fluid in the brake circuit that had no leak, still giving you brakes. I could be wrong however.

Actually, I found out the hard way (need to bleed the system better next time ) that there is a plunger, serves two purposes. The first trips the switch (wire coming out of the top) and lights the "BRAKE" light on your dash (above the coolent temp on my '67). It also appeard to cut the fluid flow to one part of the system as a test run confirmed with the fronts not working. Unfortunately I could not get the little plunger back to center (40 years having not moved) and ended up replacing it with a prop valve and all is good.

This was done during my Scarebird conversion last year. As the original poster mentioned, less pedal effort overall with better stopping ability. Much improved over the original drums Lately, I have been toying with the idea of adding the 87-93 power booster just for giggles.

DJCarbine & 68conv4sp, I have a T-5 with the original z-bar using Hedman long tube headers and they work fine. Had to lower the power steering ram though. The headders were purchased about 10 years ago, just the painted variety. Can't comment on the tri-ys, never used them.

 

[DJCarbine]

Hehe... on my 66 distribution valve for the original single resevoir MC, there is no wire coming out of the top, and only a single inlet which leads me to think there was no plunger pre-67. Oh well, what counts now is that I can stop

 

[Cool67]

Actually, I found out the hard way (need to bleed the system better next time ) that there is a plunger, serves two purposes. The first trips the switch (wire coming out of the top) and lights the "BRAKE" light on your dash (above the coolent temp on my '67). It also appeard to cut the fluid flow to one part of the system as a test run confirmed with the fronts not working. Unfortunately I could not get the little plunger back to center (40 years having not moved) and ended up replacing it with a prop valve and all is good.

This was done during my Scarebird conversion last year. As the original poster mentioned, less pedal effort overall with better stopping ability. Much improved over the original drums Lately, I have been toying with the idea of adding the 87-93 power booster just for giggles.

DJCarbine & 68conv4sp, I have a T-5 with the original z-bar using Hedman long tube headers and they work fine. Had to lower the power steering ram though. The headders were purchased about 10 years ago, just the painted variety. Can't comment on the tri-ys, never used them.

I read the same thing in a mustang manual last night.

How did your Scarebird conversion go on your 67?

I'm considering doing the Scarebird conversion too but I have the original 14" styled wheels on my 67. Which means that the rotors would have to be machined to fit.

 

[Stangboy67]

I read the same thing in a mustang manual last night.

How did your Scarebird conversion go on your 67?

I'm considering doing the Scarebird conversion too but I have the original 14" styled wheels on my 67. Which means that the rotors would have to be machined to fit.

Sorry for the delay, I have been out of reach of a computer for awhile.

The conversion went quite well for me. I am pleased with the results and the braking is much nicer, better feel, less pedal effort, consistant breaking action with fade no-longer an issue. The only problems were with the previously mentioned distribution block and my aftermarket 14 inch wheels. (don't ask ) They needed just a bit of grinding (1/8 inch), but that was with the early version, not the new setup Scarebird has.

I would like to add a power booster to the system just to make the pedal feel more like modern power assist. I like it as it is which is a vast improvement over the drums, however the wife would like it to be easier.

 

[Cool67]

Sorry for the delay, I have been out of reach of a computer for awhile.

The conversion went quite well for me. I am pleased with the results and the braking is much nicer, better feel, less pedal effort, consistant breaking action with fade no-longer an issue. The only problems were with the previously mentioned distribution block and my aftermarket 14 inch wheels. (don't ask ) They needed just a bit of grinding (1/8 inch), but that was with the early version, not the new setup Scarebird has.

I would like to add a power booster to the system just to make the pedal feel more like modern power assist. I like it as it is which is a vast improvement over the drums, however the wife would like it to be easier.

Thanks for your input. I'll probably start my conversion soon.

 

[Cool67]

Actually, I found out the hard way (need to bleed the system better next time ) that there is a plunger, serves two purposes. The first trips the switch (wire coming out of the top) and lights the "BRAKE" light on your dash (above the coolent temp on my '67). It also appeard to cut the fluid flow to one part of the system as a test run confirmed with the fronts not working. Unfortunately I could not get the little plunger back to center (40 years having not moved) and ended up replacing it with a prop valve and all is good.

This was done during my Scarebird conversion last year. As the original poster mentioned, less pedal effort overall with better stopping ability. Much improved over the original drums Lately, I have been toying with the idea of adding the 87-93 power booster just for giggles.

DJCarbine & 68conv4sp, I have a T-5 with the original z-bar using Hedman long tube headers and they work fine. Had to lower the power steering ram though. The headders were purchased about 10 years ago, just the painted variety. Can't comment on the tri-ys, never used them.

You mentioned "need to bleed the system better next time". I'll probably run into the same problem you encountered with the distribution block when I do my conversion, so, how would you recommend that I do the bleeding differently so as not to end up with a stuck plunger?

 

[krash kendall]

You guys are confusing a distribution block with a proportioning valve.

 

[Cool67]

You guys are confusing a distribution block with a proportioning valve.

The attached picture is of my so called "distribution block".

The attached drawings are from a 67 Ford Mustang shop manual. The shop manual called it a "Pressure Differential Valve".

I'm not sure what a proportioning valve looks like so please, educate me.

 

[Stangboy67]

The attached picture is of my so called "distribution block".

The attached drawings are from a 67 Ford Mustang shop manual. The shop manual called it a "Pressure Differential Valve".

I'm not sure what a proportioning valve looks like so please, educate me.

Looking at the pix of your distribution block, errr...PDV, I am curious to the pinkish fitting at the top rear of the valve (block). It looks as though there is not a brake line plugged in there?? although it could be the angle of the pix. If there isn't a line going in there, you either don't have one set of brakes working (you probably would have noticed) or you are running both sets (front & back) off of one reservoir of your master cylinder

As far as the proportioning valve question, here is a link that will help explain. http://www.chevyhiperformance.com/techarticles/71398_install_brake_proportioning_valve/

Please excuse the chebby link, but the article does a good job explaining the valve and the reason for them as well as a good pix of one.

My problem was that I didn't bench bleed the master cylinder well enough (half hearted attempt, doesn't pay to be in a hurry sometimes). When I installed it on the car, apparently one side pressurized long before the other and the plunger moved, never to be coaxed back again.

 

[krash kendall]

The PDV and Proportioning valve are the same thing. The earlier cars had a distribution block that did not have the ability to isolate from front to rear in the event of a brake line failure.

 

[Stangboy67]

The PDV and Proportioning valve are the same thing. The earlier cars had a distribution block that did not have the ability to isolate from front to rear in the event of a brake line failure.

The blocks on the '67 keep the two (front and rear) isolated, which was my concern with Cool's setup in his photo. It looks like that was bypassed. I assumed since he was using a '67 manual, he also had a '67 stang I don't know what the earlier ones look like or operate for that matter.

The problem with the PDV (the original) vs the new Proportional valve (like that in the article) is that it is not adjustable. This generally isn't an issue though until you toss the disks on the front of the car and you wish to make sure the front/rear bias is good.

 

[krash kendall]

Yup!

 

[Cool67]

It's all connected, just a bad angle. Attached is a better picture and a cutaway view for anyone interested in seeing what the inside looks like.

Thanks for the additional info and the link.

 

[Cool67]

The PDV and Proportioning valve are the same thing. The earlier cars had a distribution block that did not have the ability to isolate from front to rear in the event of a brake line failure.

Thanks for clearing up the confusion.

 

[5.0ina66]

Cool stuff! Got my scarebird brackets Monday, Dunno if I can get it to the point where it needs brakes by September or not though, so they may have to wait

 

[gsxrken]

You guys are confusing a distribution block with a proportioning valve.

All wheel drum cars don't have prop valves b/c the wheel cylinders are sized differently Front and Rear, which serves the same purpose.

What I am interested in hearing more about is that both these guys seem to have had braking issues with the shuttle valve out of position... I have been led to believe that that shuttle is strictly for the light. Are you two saying it did interfere with brake fluid flow too, and that centering it (or getting a new one) imporved your braking?

 

[krash kendall]

If you blow a brake line, the prop valve or PDV shuttle will travel to port of low pressure (the one with the blown line), blocking it off so you don't lose all your fluid. The earlier drum cars had a block that was strictly for splitting the lines front and rear and didn't have any safety features.

The light switch tells you when you need to inspect the brakes for leaks or an empty reservoir.

 

[mustangdave]

I had/have this problem when I parked my 67. After replacing lines,wheel cylinders,etc... and bleeding two cans of fluid, the valve was off center and brakes were almost non-existent. So yes, it can affect braking.