Drum to disc--New brake pedal assy. needed?

[CarFreakGT]

One of the p.o. of my 68 coupe converted from drum to power discs in the front. My brake lights work, but only when the brake pedal is mashed pretty much all the way to the floor. In essence, my brakes work fine, but those behind me don't realize that I'm on my brakes until I'm already stopped! I don't drive the car right now as I'm trying to do some work on it, but I won't drive it at all until this is resolved.

I did a search, and I initially thought I just needed to change out to a switch for power brakes. I've done that, but still have the same problem. Do I need a different pedal assembly as well? I seem to remember some reference to the power brake pedal being longer, but I can't remember where I saw that. Anyone have an idea? Thanks!

Bryan

**By the way: auto trans, front power discs, rear stock drums

 

[67coupe351w]

By far the easiest and cheapest solution would be to add a pressure switch to your brake line.

You could easily add it in between the master cylinder and dist. block without having to re-flair any lines. Most auto parts stores sell short sections of brake line with both ends pre-flaired.

Search www.summitracing.com for a brake light pressure switches. For example P/N: PRF-80171 is only $12.


*This is all based on yur brakes currently function acceptably with peddle setup you have.

 

[ultrastang]

By far the easiest and cheapest solution would be to add a pressure switch to your brake line.

You could easily add it in between the master cylinder and dist. block without having to re-flair any lines. Most auto parts stores sell short sections of brake line with both ends pre-flaired.

Search www.summitracing.com for a brake light pressure switches. For example P/N: PRF-80171 is only $12.


*This is all based on yur brakes currently function acceptably with peddle setup you have.

If you can't find a factory-type switch that will work correctly, then you can do what I did on my brake pedal when I adapted an '87-'93 Mustang 5.0L Fox brake booster to my '68. --assuming IF you have a stamped bracket at the top of your pedal like the one shown in the lower part of this picture: http://www.ultrastang.com/Images/Scanned/Sept2002/11t.jpg

I installed a Microswitch which activates the instant the brake pedal is stepped on. http://www.ultrastang.com/Images/Scanned/April2003/02t.jpg

More on this in following link; http://www.ultrastang.com/Ultrainfo.asp?Page_ID=16

 

[CarFreakGT]

Thanks for the info, guys! I will definitely check those options out.

 

[fasttback]

After an auto to manual switch on my '67 I had to shim the brake switch with a thin strip of metal to get it to work.

 

[zookeeper]

I know you probably already know this, but you do know that manual brake pedals and power (disc or drum) brake pedals are different, right? The power pedal pivot is much higher therefore taking away some of the mechanical advantage needed for manual brakes. Maybe this is what's causing your problem. Or maybe not...

 

[CarFreakGT]

I know you probably already know this, but you do know that manual brake pedals and power (disc or drum) brake pedals are different, right? The power pedal pivot is much higher therefore taking away some of the mechanical advantage needed for manual brakes. Maybe this is what's causing your problem. Or maybe not...

Thanks--that's what I was curious about. I have gone from drums to power discs, but I don't know if it was originally a power brake car. I don't think it was, but I don't know how to be certain. Does that mean I definitely need a new pedal assy.? Should I try the different switch first? If it's a safety issue, I will definitely do the new assy.

 

[truck90278]

We converted from all drums to power (after market booster) 4 wheel discs on our 65. When the brake light switch was installed on the standard brake lever (correctly installed with bushing) the brake lights would not come on at all. The company (ABS Power Brakes) removed the bushing that goes between the switch and the pedal. This left the pedal very loose. We are in the process of rebuilding the car and we are adding the SSBC combination adjustable proportioning valve and pressure brake switch. Then, we can fix the sleeve properly on the brake pedal for a nice fit. and still have brake lights and the proportioning valve

 

[CarFreakGT]

Yes, it seems like that pressure brake switch would work regardless of the set-up. So long as my brakes are working properly (and they seem to be), it seems like it may be the least expensive option.

 

[jcode68]

depends on the kit

Some aftermarket brake kits are designed to use the shorter manual brake pedal. I would find out what brand kit was used and go check their website or call them. If you don't have the right pedal, it still will work but will not realize the maximum performance of the brake system. I used SSBC kit and swapped in OEM booste to remsun compatible with my hydraulic clutch unit. This required a pedal swap. Hit the link in my sig and view the write up I did on my swap. All that said, the pressure switch is a nice solution to your problem as others pointed out. Hope this helps.

 

[67efivert]

i had the same problem when I used the fox body booster on my car I just used the fox switch and spliced the pigtail into the original wiring the spring in the switch was softer so it turned on faster

 

[zookeeper]

The easiest way to tell if you have a manual pedal, or a power pedal is to look at the pivot. If it pivots from the same pin as the clutch, it's manual. If the pivot is closer to the firewall, on a separate pin than the clutch, it's intended for a power brake setup.

 

[CarFreakGT]

My car is an automatic.

 

[zookeeper]

Well then, your brake pedal would really be on a different pivot than the clutch pedal, wouldn't it? Seriously though, power brake pedals pivot close to the firewall, rather than about the midpoint of the brake support bracket.

 

[CarFreakGT]

Well then, your brake pedal would really be on a different pivot than the clutch pedal, wouldn't it? Seriously though, power brake pedals pivot close to the firewall, rather than about the midpoint of the brake support bracket.

LOL. I do wish it were a stick, though!

Seriously though, power brake pedals pivot close to the firewall, rather than about the midpoint of the brake support bracket.

Thanks, zoo. I'll check it out.