Technical Question on Brake Pad Bedding

Thanks so much. The speedway calipers in the kit are for a 69-72 GM (Chevelle). I imagine the pads are also 69-72.
I bought the pads at NAPA and told them I needed 72' Chevelle pads.

I wonder if I should just file down the Napa ones so they are thinner? Or are organic quality pads from Speedway probably ok and I should just order a set and hope they come in better condition? Or screw it and use those ones I have with the chips/chunks missing. hmm

 

I've seen banged up pads and shoes before and they have always been okay once installed. Have you swapped pad sets side to side? It may be worth a look-see while the car is apart.

I definitely do not recommend filing or otherwise reducing pad thickness to fix what you got going there.

 

Thank you. I will try swapping sides. I measured the pad thicknesses for both sides and they were pretty close but I'll try this anyways.

I had seen the chunks and thought the Speedway pads were junk. This is why I went to Napa and got the semi-metallic pads. I want more stopping power but am not sure if those semi-metallics were a waste of money?

Speedway replacement ones are $15.99. The Napa ones cost me $48 with tax

 

Can you post up a pic of both sets of pads?
And yes, as mentioned, I wouldn't recommend grinding or filing brake pads.
Have you check all the caliper hardware for any o-rings missing?

 

Thanks. Here are the Napa ones:



Here are the speedway ones.



The Napa ones have greater overall thickness as I had measured and stated earlier.

One thing that bugs me is that Speedway provides a bolt that has the sleeve built in to it. The original 69-72 calipers come with a sleeve and bolt that are separate. This might give some extra slop to absorb and flex/bending in the caliper bracket. hmmm

 

I checked the calipers and no o-rings were missing and i had to carefully insert the bolt to avoid the o-ring coming out. Because the sleeve and bolts are not separate, it made it a royal pain on the driver side.

 

If you use lube on everything (synthetic brake lube or hi-temp white grease) things go together a lot better. I like the separate bushings myself, install those into the o-rings in the calipers.

 

Just my opinion, I would rather have the pin and sleeve separate.
I must be behind the times, as I didn't know they come as one now.

 

Thanks! I used the synthetic brake grease just about everwhere, all over the o-rings any where the pads touch the calipers, etc. Unfortunately the bushings don't come separate from the bolts. The bushings were in the calipers but they had to be removed so the caliper/bolt assembly from speedway could be used. Annoying. I can buy the caliper bolts at NAPA I suppose.

 

Thanks, probably just the Speedway kits has those. Napa sells caliper bolts that would work with these. The sleeves came with the Speedway kit though they were removed since they couldn't be used.

I'm not sure what to do now. I'm still stuck, if I can't modify the pads the only thing left to do is swap sides and see what happens.

 

clean the pads and take them back to napa, tell them they don't fit and ask for a different style.
i have done it before. there are some late model cars/trucks that i have put the "fancy" composite pads on and i thought the car/trucks brakes were terrible, even after many break in miles they have taken them back and exchanged them. sometimes the organic pads stop better and wear the rotor less.

 

Thank you very much for this advice. I threw away the NAPA box they came in.. ugh I did this right before I had to move out of my house. Did you return yours with the original box?

Maybe I should just order a replacement set from Speedway, or does anyone think the ones I showed in the photos are acceptable to use even with the chunks gone? These are the ones from Speedway:

http://www.speedwaymotors.com/Speed...c-Brake-Pads-GM-Mid-Size-1969-1977,34378.html

 

Your overthinking it to much. Put in the Speedway pads and see how it works.

 

Will do! I doubt NAPA will take the pads back without the original box (I do have the receipt) but I guess I can try.

The chunks missing in the Speedway pads, etc are nothing to worry about right? I'm referring to the quality of the material if they may lead to more chunking

 

Chevelle calipers are single piston, So one side rides along, usually the outside, and the inner has the piston, the caliper slides back and forth on pins to clamp and release.

Check that the caliper is sliding.

Tighten up the rotor with lugnuts, Bolt up both calipers with no pads and measure the side without the piston, to the rotor face. Should be the same side to side. If not, swap calipers side to side if possible, remeasure. If still uneven, shim your caliper bracket.

Put the pads in and double check, the side without the piston should travel closer to the rotor, the piston side has more movement.

No issue scuffing down pads, but make sure everything lines up properly first.

 

Thanks. If the pads are off and the calipers can slide back and forth, I don't think I can measure the caliper face to rotor face distance on both sides and expect to get the same result?

 

It looks like the NAPA pads are shimmed while the speedway pads are not. Removing the shims will gain you some clearance. I like to use Silglide on the O rings.

 

Thank you. I've read a little more and I want less pedal effort so organic pads seem like a better choice given I drive the car so little. I will return the NAPA pads if they let me.

As I showed in one of the prior replies, the Speedway organic pads seem to fit better since they are thinner and the pad to rotor gap looks parallel.

The only thing I'm pondering is whether the Speedway pads with the chunks missing are fine to use. I know the chunks missing won't make much difference, just curious on the quality of the material.

 

They don't slide easily, it's not like they flop around. One side is fixed, the other moves on pins. The chevelle caliper is pretty basic. You may have to bleed the system to use hydraulic force to move the caliper on the pins. Checking the caliper position to rotor position loaded and unloaded with hydraulic power is a basic step to ensure the parts from multiple suppliers are doing what they are supposed to.

I am trying to offer assistance. If you already "know it all", I wish you luck on your brakes.

 

Thanks. It makes sense I need to use hydraulic power to get the caliper/pads to sit at the right position. The measurements loaded/unloaded make sense.

I already know the NAPA pads barely clear the rotor with the caliper, even when not installed on the caliper bracket. Therefore the pads need a bit of modification either way. Some have advised against doing that so I'm cleaning them up and returning them (if they let me).

I will use the Speedway pads with the chunks missing but will file/sand if I feel burrs around the missing chunks edges. I don't mind if organics make more dust, I'm going for less pedal effort required and can clean the wheels every time I drive if I need to since its 1-2 times a month at most.

 

Pads returned to Napa that was easier than I thought.

 

i like napa, i have heard all kinds of stories, but they have always took care of any problems. then again, i spend lots of money a month with them. they will turn them in as defects.
i bet most guys would have just run them, and they would have worn in fine. you have to do what is comfortable for you!

 

Thanks, I have spent quite a bit with NAPA too the last 6 months.

By the way the NAPA inner pad was thicker than the outer pad. The Speedway ones have same thickness for inner and outer.

I think organics are better anyways, I want less pedal effort and don't mind cleaning the wheels in exchange for that. I'll use the Speedway ones even with the chunks missing, no one seems to think that is a bad idea.

 

The inner brake pad puck and plate are normally thicker on D52 brake pads.

 

You are right. According to the measurements I made earlier, Napa outer is 0.090" thicker than the inner. The Speedway outer is 0.057" thicker than the inner.

 

I went to O'reillys and got a pair of semi-metallics. I was going to get the organics but the guy said the 72' Chevelle oem is semi-metallic and organic would just blow dust everywhere and are typically bought by people just looking to sell a car.

I measured them and they are:
0.544" outer
0.605" inner.

A little thinner than the NAPA ones but not by much. I will see if they even go on and the rotor still spins. If I have to sand them down I rather just go with a better grade from NAPA like the ones I had returned. It's too much work to put this car on jackstands and move my roommates stuff each time so if I put the Speedway organics and have an issue or far too much dust is getting on the rims, that will suck.

I'm thinking Speedway maybe cut down the pad thickness for these kits as was mentioned earlier by someone else.

 

Semi met's blow dust also. As for speedway grinding pads down, doesn't make sense.
It's not that hard to match up a GM rotor and pad combination for a changeover kit.
If that's the case then you would have to grind pads every time there changed.

 

That is true.

 

dust wipes off

 

I tried the other Mustang II bracket set mad by CPP. I had bought it earlier in the year just for checking I wouldn't hit the strut arm if I bought a big brake kit.

With this CPP bracket the caliper on the driver side bolts up and it slides with some moderate force by hand. With the speedway bracket it did not slide at all by pushing hard. Also as I said yesterday, the driver side caliper piston doesn't go in as far as the passenger side. I'm going to always have to find pads that are thinner in the future ...annoying.

I'm so mad. I should make this right. I'm going to NAPA to buy their eclipse line of calipers and a better set of pads and the caliper bolts that don't have the sleeve built-in.