Disc brake conversion on the Gasser

[zeek]

I was amazed to find a company that made a disc brake conversion kit for a 1938 Chevy stock spindle...:hurray: Simple and straight forward swap with the supplied bearing adaptor and parts list. I used a '76 Camaro rotor and outer bearing but the kit required a 70's Mustang inner bearing.

ECI supplied the brackets, bearing adaptor and hardware.
https://ecihotrodbrakes.com/catalog.html

[StaticCling]

Interesting. Do they supply the calipers?

[zeek]

Interesting. Do they supply the calipers?


You can buy the complete kit, which includes rotors, calipers and brake pads. Or you can buy the basic kit and then get the calipers and other parts at your local auto parts store. In my case, it would have cost $190 just in shipping for the entire kit compared to 25 bucks for the basic. For the cost of shipping, I purchased all the needed parts locally. :seasix:

[BayouCountry]

Gotta love it.

[GTOguy]

Interesting. Gassers in the day used drum brakes because they had less drag than disc brakes. I would have kept the drums...they were mint, which is rare. All due respect, of course.

[sublime1996525]

Nice!

[Rodnok1]

Front brakes... who needs front brakes... :leaving:

[zeek]

Interesting. Gassers in the day used drum brakes because they had less drag than disc brakes. I would have kept the drums...they were mint, which is rare. All due respect, of course.

They also only went in a straight line and rarely if ever saw street use. MY Gasser will be primarily street driven and rarely be on the track....so...there ya go...:seasix:

I fail to see your comparison of drag on drums vs disc....:confused5:

[GTOguy]

No need for a comparison on drag values between drums and discs....60 year old info available anywhere and common knowledge at the time.

That said, since your car will be street driven, discs are a smart and safe move. The non-energizing '30's drums have nowhere near the stopping power of the self energizing drums that came out in the '50's. I had stock drums on my '37 and '47 Chryslers and they did not stop very well compared to my drum brake '60's era cars. You have a killer project there, and I approve!

[markids77]

Is there room in there somewhere for a two pot master cylinder?

[GTOguy]

These old rigs originally had under the floor master cyls and frame-mount pedals. Sometimes a lot of room, sometimes not. Many 'upgrade' to hung pedals like '60's and later cars. Only Zeek will be able to answer this one for certain.

[zeek]

No need for a comparison on drag values between drums and discs....60 year old info available anywhere and common knowledge at the time.

I cant even begin to imagine the infinitesimal difference of drag between drum and disc brakes. Probably one of those wives tales that folks believed back in the day since disc brakes were fairly new back then.



Is there room in there somewhere for a two pot master cylinder?

Yes...plenty of room on the firewall for the upgrade. Something that is a must along with a proportioning valve install. I planned on doing both...:seasix:

[GTOguy]

The advantage in drag of the drums over the discs was indeed very small. But those guys would do anything to get even the smallest perceived advantage. Is your gasser already converted to hung pedals off of the cowl vs the factory frame mount pedals that go through the floorboards?

[JRD77VET]

I cant even begin to imagine the infinitesimal difference of drag between drum and disc brakes. Probably one of those wives tales that folks believed back in the day since disc brakes were fairly new back then.





Yes...plenty of room on the firewall for the upgrade. Something that is a must along with a proportioning valve install. I planned on doing both...:seasix:

I completely agree the difference is extremely small. The NASCAR guys would push back the disk brake pads when they did qualifying on the super speedways. No touching the brakes until you were done.

The one guy who rented a spot in my grandfather's barn raced a '69 Camaro and he kept the drum brakes for reduced drag.

[Chuck A]

very nice, indeed

[zeek]

The advantage in drag of the drums over the discs was indeed very small. But those guys would do anything to get even the smallest perceived advantage. Is your gasser already converted to hung pedals off of the cowl vs the factory frame mount pedals that go through the floorboards?

Pedals are hung from behind firewall not frame mount. I just got the calipers yesterday. I was going to use caliper paint do dress em up but the came with what appears to be cadmium plated so I just left them silver.:yesnod:

While I dont doubt for a minute that NASCAR and drag racers believed the disc brakes had more drag, I would love to see some stat's showing the difference in times between the two...:yesnod:

[ptindall]

I completely agree the difference is extremely small. The NASCAR guys would push back the disk brake pads when they did qualifying on the super speedways. No touching the brakes until you were done.

The one guy who rented a spot in my grandfather's barn raced a '69 Camaro and he kept the drum brakes for reduced drag.

Its pretty simple. Drums have springs that pull the shoes away from the drums. Jack up the front end of a drum brake car and spin a wheel. It will free spin for a long time. Disc brake pads remain very close to the disc if not touching. Try free spinning a disc brake wheel. It will not spin neary as well as a drum brake car.

[Strats-N-Vettes]

Its pretty simple. Drums have springs that pull the shoes away from the drums. Jack up the front end of a drum brake car and spin a wheel. It will free spin for a long time. Disc brake pads remain very close to the disc if not touching. Try free spinning a disc brake wheel. It will not spin neary as well as a drum brake car.


:iagree:
And an adjuster that can ensure the shoes are away from friction contact.

[TheHammer]

Its pretty simple. Drums have springs that pull the shoes away from the drums. Jack up the front end of a drum brake car and spin a wheel. It will free spin for a long time. Disc brake pads remain very close to the disc if not touching. Try free spinning a disc brake wheel. It will not spin neary as well as a drum brake car.

need to grind down the rotors

[GTOguy]

Its pretty simple. Drums have springs that pull the shoes away from the drums. Jack up the front end of a drum brake car and spin a wheel. It will free spin for a long time. Disc brake pads remain very close to the disc if not touching. Try free spinning a disc brake wheel. It will not spin neary as well as a drum brake car.

THIS^^^. The disc brake caliper seals help keep the pistons from pushing the pads into the rotors while at rest due to torsional tension of the seal (square cut O ring), but the pads do rest against the rotor. Even the Toyota's with the external spring clips running across the pads drag. Drum brakes can be backed off enough to not make ANY contact, and will still work. We all know from doing relines or bearing re-packs on disc brakes that if the pads are NOT resting against the rotor, the pedal goes to the floor until you pump it enough to push out the piston so they do.

[zeek]

Great answers here, but my question is....What are the times with brake shoes VS disc brake? I bet there is no difference at all....just one of those wives tales racers talk about.:yesnod:

[JRD77VET]

Great answers here, but my question is....What are the times with brake shoes VS disc brake? I bet there is no difference at all....just one of those wives tales racers talk about.:yesnod:

Target shooting, drag racing, road racing, a BIG part of it is mental. :yesnod:

When I was racing go karts, my FIL said "I bet if we taped a rubber chicken to your helmet and you won, everybody would have a rubber chicken next week". :rofl:

[zeek]

Target shooting, drag racing, road racing, a BIG part of it is mental. :yesnod:

When I was racing go karts, my FIL said "I bet if we taped a rubber chicken to your helmet and you won, everybody would have a rubber chicken next week". :rofl:

Troof!!:rofl: :cert: