MS wrote:

On 67-70 with manual trans and power brakes, the brake pedal will be about 1” lower than the clutch pedal.

What exactly do you have?

 
66 t5 MS power brake conversion, 89 Mustang 4 cyl booster, 2000 Mustang 6 cyl mc, discs front and rear, MS clutch cable. I did the conversion myself with your parts.

TKOPerformance wrote:

The stock clutch pedal location on my '67 was absurd.  At least 1" longer and 1" higher than the brake.  Not the hot ticket for driving fast.  I simply built an adjustable stop to set pedal height, then cut the pedal pad off the arm, repositioned it and welded it back so they were even.  They do not sit next to each other stock.  If you're used to driving a newer car with a stick you'll be disappointed in the stock location.  You come to understand that the ergonomics in these cars were at best an afterthought, and more often than not a non thought.  It can all be corrected, but it takes some fiddling and fabricating. 

 
My clutch pedal is fine it's the brake pedal that sits to low. The brakes work fine but the pedal is almost even with the accelerator. By time the brakes are grabbing the pedal is almost on the floor.

TKOPerformance wrote:

What year car?  Not sure about '65-'66, but '67 used different pedals for manual and power brakes that mounted at different points in the pedal support.  Trying to use a manual brake pedal with power brakes would result in exactly what you describe. 

 
You are exactly right. I did some measuring and it's not as bad as it appears. The brake pedal is 4" from floor to pedal. When I pressed the pedal as far as it will go it's at 2 3/4". So that give me an 1 1/4" of travel with 2 3/4 inch to the floor. It's kind of wonky looking but it works. I think I can live with it. If anything I might put a block or something on the pedal just so it's a little higher than the gas pedal.

TKOPerformance wrote:

Again, not knowing what year the car is this may or may not be accurate, but the reason the pedals are different, and mount in different locations is because the pedal ratio needs to be different between manual and power brakes.  Without changing the pedal you are not able to apply the proper amount of force to the master cylinder.

In a '67, using a manual pedal after converting to power brakes will create brakes that effectively barely work.  I learned this the hard way when I converted to power disc/drum 25 years ago.  The kit I received from SSBC did not include, nor say anything about the difference in the pedal.  Being a foolish kid I thought I could just make up a pushrod extender so the pedal I had worked (I hadn't figured out yet why it didn't work).  When the extender failed I lost braking ability.  Fortunately I was able to come to a stop and avoid hitting anyone or anything, but it was scary as hell. 

So my advice, if this is your situation, get the right peal in the car.  I'll add that if you're measuring pedal travel without the engine running its not accurate, because there's no vacuum in the booster.  When you start the engine the pedal will drop even farther. 

 
It’s a 66. Pedal has been modified for power  brakes using the Mustang Steve conversion.

We're now in MS territory.  I'm not familiar with the conversion, having not done one myself, so I can only really comment on stock vs. stock.  I'm sure he'll chime back in here momentarily. 

MS wrote:

Just got back in town. Been on SOS TEXAS FYIFORD MUSTANGER TRIP.

Did you modify the pedal or did you buy it already done from us?  The dimensions on the pin are critical, front to back.  We have a jig to get them perfect, but sometimes a customer’s drill bit will walk a little bit.

The power brake pedal is designed to sit about 1” lower than stock. Since it has a 4:1 ratio instead of stock 6:1, the total travel is alot less than a stock pedal.

If your pedal is traveling more than 2” total, there is slack somewhere in your system.
1. Usually result of rear brakes (drum or disc) not properly adjusted.
2. Air in the system.
3. Booster output shaft adjusted too short.
4. MC bore too small
5. Booster input shaft that connects to the pedal pin is not adjustable, and is an integral part of the booster. It COULD be cut in two, threaded and an adjusting sleeve installed, but that goes against my rule of modifying “wear” parts that may have to be replaced someday. I do not see a future in having to modify a new part in order to replace a modified part, plus the warranty is immediately voided.  If you want to make it adjustable, it can be done, but needs to be done in a good strong way.

 Thanks Steve. I get what you mean about modifying new parts. I installed the pin myself per the instructions that came with it. I was very careful and measured several times, center punched it and used a good drill bit so I'm reasonably sure it's correct. I took it for a test run today and it stopped fine. I've had this brake locking problem that turned out to be improper clearance between booster pin and mc. Mines not adjustable so I used flat a washer, one each side, to space it out and it worked. I guess I'll just have to get used to the pedal height the way it is.

Mine is perfect for hell toe but it's a street cruiser. Although with such a good heel toe arrangement I might be doing some spirited driving. I figure it's good for the summer, then I might just modify that booster.

MS wrote:

An easier way to fix it is to install a MustangSteve BBK ballbearing shaft kit on the pedal pivot. You can mount the bearing retainer towards the front of the car about 1/8” to make the brake pedal sit higher.

Those washers between the booster and MC lower the brake pedal 4.2x the thickness of the washer.

 
I already have the bearing kit installed. I'm convinced my options are modify the pedal rod or replace the booster with one that has an adjustable output pin so I can eliminate the washers. Of course there's always the option of just driving the thing and getting used to it which, given its hot as hell and terribly humid, is probably what going to happen.