vipervetteguy

The previous owner of my 66 installed all new rotors, calipers and pads. (using OEM spec parts) Even under very hard braking, I can't get a tire to lock up at all. (manual brakes) I understand it's an old car, but I need better brakes and don't want to convert to power brakes.
I am going to start with a street pad with much more initial bite (maybe the new Hawk pad). I also read somewhere to check that the master cyl rod is into the correct hole on the brake lever. Which hole would be the correct one?
The pedal is isn't soft at all, so air in the lines isn't an issue. Any other ideas or is this just how the brakes are meant to be?

mashinter

The push rod should be in the upper hole on the pedal for manual brakes.

Let us know how the Hawk pads work. Pedal force to lock-up is very high with factory pads.

edit: Here's a quote from Zora in SAE paper 650275: "It is interesting to note that the maximum deceleration -- that is, to the frictional ability of the tire -- is not easy to attain."

dplotkin

That is not as designed. I have manual brakes on my 65 and except for a little more effort they will hook up & lock as all properly working brakes should. Assuming you have the correct master cylinder bore and everything else is correct I suspect you have trapped air and you should bleed all 4 all over again. Are you using DOT 3 or 5? DOT 5 requires special attention to pouring. If you cannot lock up your brakes, you do not have working brakes.

Dan

Adam@Amp'dAutosport.com

If interested take a look at the Carbotech 1521 brake pad.

Carbotech™ Bobcat 1521™ The Carbotech Bobcat 1521™ is our high performance street compound that is our most successful compound. The Bobcat compound is known for its awesome release and modulation, along with unmatched rotor friendliness. Like our AX™ & XP™ line of compounds, Bobcat 1521™ is a Ceramic based friction material offering minimal rotor damage and non-corrosive dust. Bobcat 1521™ offers outstanding performance, even when cold, low dusting and low noise with an excellent initial bite. This compound’s virtually perfect linear torque production provides incredible braking force without ABS intervention. Bobcat 1521™ operating range starts out at ambient and goes up to 900°F. Bobcat 1521™ is suitable for ALL street cars, perfect for your tow vehicle, police cruiser. The Bobcat 1521™ compound has been found to last two-three times longer than OE pads you can purchase at a dealership or national retailer. That’s one of the beauties of Carbotech Ceramic brake compounds. Bobcat 1521™ is NOT recommended for any track use.

babbah

For a 1967 Corvette - Carbotech Brake Pads, part # CT8 yes?
What is the price and where/how to buy at lowest cost? Do you give discounts to Corvette Forum members?

troutster71

When I first purchased my '67,(pre internet) I too, could not lock up the manual brakes. Hell, high pedal effort just to slow down quickly! Pedal was also rock hard. I started checking into new/ different pads. Then, didn't do anything for a while, just lived with it. Later, when I was getting the car painted and had the engine compartment stripped, I noticed the master cylinder was a power brake unit, 1-1/8" as I recall, from looking in supplier catalogs, and real, old school, book-like reference materials.
Ordered the correct 1" dia manual m/c, and lo and behold, with a correct bleed and same pads, a new car as far as the brakes were concerned.
Bottom line, verify your M/C size, (may have to take it off to do so).

Hope this helps, GA

I don't know which hole is correct for your '66. I'll look on my '67........

63Corvette

ALL of the C2 vintage race cars use stock C2 disc brakes. They work fine for vintage racing.......including for high horsepower cars like those run by Duntov Motors race cars. If the brake are properly set up with stock hardware they will work fine. Use of stock or optional brake pads is your choice, but for one stop cold, any pads will lock the tires and bring the car to a stop from any speed attainable.......trust me on that

Godholio

If you switch to ceramic pads, don't be surprised if you need to replace the rotors as well. There may not be damage, but it's probably going to be unbelievably noisy.

Adam@Amp'dAutosport.com

You can purchase direct from us call me at 216-780-8825 or go direct to this link and use promo code z28 for forum pricing. I offer 5% discount. http://ampdautosport.com/corvette/pr...front-ct8-1521

Retail CT8 $139

Sky65

My guess is as previously mentioned. Push rod in on the wrong hole on pedal arm or master cylinder too big for manual brakes. Or both!

Tom

troutster71

On my '67, the pushrod is in the hole farthest from the pedal. Dont know if your '66 is the same.
Cheers, GA

JohnZ

All '63-'67's are the same design:

Manual brakes = top hole.

Power brakes = bottom hole.

Ol Blue

Might not be of interest but my 63 has an extra hole for the clutch linkage that lowers the clutch pedal to the same height as the Power brake pedal. I set it up that way as soon as I bought it, then later set it up for shorter throw shifts too.

vipervetteguy

So far I've verified that the master cyl rod is through the top hole , as suggested. Now can I get some help verifying that I have the correct master cyl?

TCracingCA

You got plenty of help on the rod hole and M/C sizing, but check them (calipers) all carefully for piston engagement/movement! You should phone a friend to step on the pedal of each corner jacked up while you see if any are still spinning. They all should lock up each wheel! Also you mentioned OEM (how old are these pads?) (Are they used?) (Are the faces glazed? Shiny? Signs of heat or improper break in?)(Is the car pulling to either side at all?) Etc.?

Ps Manual 65-66 Discs non power is #3866446 (Bendix 618690) and I hope some cheapscape Company didn't sleeve down the stock 1" bore!

66since71

Pads are SAE standard rated for coefficient of friction. It's a two letter code. First letter is for the rating cold. Second is for hot. Higher letters are better. Don't expect good performance from anything less than FF. Rating is visible on the edge of the friction material.

Harry

MikeM

The correct 1965/66 non-power MC looks very similar to this one. I don't know of any other usage for one with this general configuration.

http://www.autopartswarehouse.com/sk...FbBDMgod7CUA6w

toddalin

I had a similar problem until I switched to the Andy Porterfield R4-S pads. They are GREAT!

R4-S – The performance street pad, this pad offers the least dust and squeal of any of the street pads we carry. It is very rotor friendly and will last as long as your stock pad but typically they last a little bit longer

00fxd

In my past life as an automotive parts-man we learned from manufacturers reps that one can't always rely on the casting # to identify the bore. Occasionally the same MC casting # will be used for various bores.

vipervetteguy

I'll check the mc asap. If that is inconclusive, I'll try pads with more initial bite. I can always use them later if I find the mc has the wrong bore.