1962 F85 Brake conversion

[Friartuck]

Asking a question on behalf of a friend who recently acquired a '62 F85 Cutlass:

Is there a conversion package availble to change over the front wheels from drum to disk brakes, while preserving the original four lug wheels?

[joe_padavano]

Asking a question on behalf of a friend who recently acquired a '62 F85 Cutlass:

Is there a conversion package availble to change over the front wheels from drum to disk brakes, while preserving the original four lug wheels?

The only ones I've seen also change to a 5 x 4.5" bolt pattern

[NTX5467]

When changing from drum to disc brakes, on any of the pre-1970 era GM cars, you ALSO have to have wheels which were configured, on the inner side of the rim, to clear the disc brake caliper. This is one reason that many disc brake factory cars came with 15" wheels, rather than 14" wheels for drum brakes. In the later 1960s, though, there were some Chevy 14" wheels which would work with the factory disc brakes on the full-size Impalas and such. You'd have to get into the 1960-era Chevy parts book to get the stamp codes (which are usually near the valve stem) to make sure which wheels are disc-brake-compatible. It is this situation which might also be the reason for the upgrade to the 5-lug bolt pattern . . . plus the fact that the cars which used disc brakes back then were all 5-lug vehicles.

There WERE some optional 15" wheels for those cars back then, but I suspect they were still 4-lug items?

Just some thoughts,

NTX5467

[joe_padavano]

There WERE some optional 15" wheels for those cars back then, but I suspect they were still 4-lug items?

Just some thoughts,

NTX5467

Correct. The 61-63 F-85 and Skylark used the 4 x 4.5" bolt pattern exclusively. An interesting bit of trivia is that the 61-63 Tempest used a 5 x 4.5" bolt circle, the only GM car to ever use that pattern.

As for the wheels clearing disk brakes, that comment really applies to the 64-up cars. There are no "disk brake wheels" for the 61-63 cars, nor were there any factory disk brake options. Any disk brake conversion will be custom and whether or not it clears the stock wheels is a function of the rotor diameter and offset selected and the size of the caliper selected. There are a number of Japanese cars that came with disk brakes, and used the same 4 x 4.5" bolt pattern. Many of these cars have rotors around 10" in diameter, since most used 13" wheels at one time or another. Most of these cars also weigh more than the 2600 lb shipping weight of a 62 F-85, so the brakes would certainly be adequate.

[NTX5467]

Thanks for that additional information and comments, Joe!

Now, with the revelation of the Tempest wheel items . . . what might it take to fit those items to a Buick or Cutlass? Although many of the available parts to do it might now be re-cast as "something else"? Might the Pontiac operatives have been planning on larger engines than the 215 V-8 all along, being the "performance division" of GM? OR putting the architecture in place should Mickey Thompson desire to do it?

Just curious,

NTX5467

[Guest oldjalopie]

Correct. The 61-63 F-85 and Skylark used the 4 x 4.5" bolt pattern exclusively. An interesting bit of trivia is that the 61-63 Tempest used a 5 x 4.5" bolt circle, the only GM car to ever use that pattern.

As for the wheels clearing disk brakes, that comment really applies to the 64-up cars. There are no "disk brake wheels" for the 61-63 cars, nor were there any factory disk brake options. Any disk brake conversion will be custom and whether or not it clears the stock wheels is a function of the rotor diameter and offset selected and the size of the caliper selected. There are a number of Japanese cars that came with disk brakes, and used the same 4 x 4.5" bolt pattern. Many of these cars have rotors around 10" in diameter, since most used 13" wheels at one time or another. Most of these cars also weigh more than the 2600 lb shipping weight of a 62 F-85, so the brakes would certainly be adequate.

Joe, I have purchased a 62 Olds just wondering if you have any further info on this conversion

Thanks

[Guest oldjalopie]

Joe, I have purchased a 62 Olds just wondering if you have any further info on this conversion

Thanks