1969 F or X Body conversion to LS Brakes

[Ranaexcavating]

I have a 69 Nova SS with the OEM front disc rear drum set up. Just picked up a complete LS front and rear disc set up and want to know if the 1969 disc brake spindle and one piece OEM rotor/hub can be used if it is machined to be used as a hub. By that I mean the rotor part of it is fully machined off to allow you to bolt the standard LS rotor.

I have searched and only found reference to using the drum brake spindle and hub when converting to the LS Is there any difference in offset that I should be aware of?

Thanks Joe

[Ranaexcavating]

I cant believe that nobody has come across this question.

Tobin can you help?

[gort69]

Pretty sure you can use the disc spindle. I used a disc spindle on a c4/c5 hybrid swap - it just requres a spacer between the bracket and the top boss.

I never considered using a machined standard rotor because drum hubs are pretty easy to find and most brackets are designed to work with them.

[Ranaexcavating]

thanks for the response. I know the spindle can be used but havent heard of anyone using the existing OEM rotor as a hub. I have a full machine shop where I work so I thought about machining the rotors into a hub instead of buying them.

[gort69]

Something in the back of my mind tells me there is a difference in offset between the drum hub and the disc rotor, but don't quote me on that. If you're building your own caliper brackets you can mock it up and design your brackets to the proper thickness to center the rotor in the abutment.

If you're using someone else's brackets, you can still do the mockup and see where it lands.

Stock drum hubs are pretty easy to find and inexpensive - I got mine for $40/pair. They will also likely require machining to get the rotor to slip over them, but you have that base covered. Beware of some Pontiac drum hubs - they can have a real whacky offset that is different from Chev-

FYI - I did a writeup at TC for the rears on a 69 Camaro - most should apply to the Nova. http://www.camaros.net/forums/showthread.php?t=161383

That's all I got! Good luck!

[Ranaexcavating]

Something in the back of my mind tells me there is a difference in offset between the drum hub and the disc rotor, but don't quote me on that. If you're building your own caliper brackets you can mock it up and design your brackets to the proper thickness to center the rotor in the abutment.

If you're using someone else's brackets, you can still do the mockup and see where it lands.

Stock drum hubs are pretty easy to find and inexpensive - I got mine for $40/pair. They will also likely require machining to get the rotor to slip over them, but you have that base covered. Beware of some Pontiac drum hubs - they can have a real whacky offset that is different from Chev-

FYI - I did a writeup at TC for the rears on a 69 Camaro - most should apply to the Nova. http://www.camaros.net/forums/showthread.php?t=161383

That's all I got! Good luck!

I read your post and it was the most informative post I've come across. You are BPOS on that forum. You've already helped me without even knowing it!

I am making my own brackets but my main concern is the wider track since I am lowered and the inner wells are already pretty close. I too thought I read there was a difference between the disc and drum of 9/16".

Thanks again

[Apogee]

There is a substantial track width difference between the Chevy disc and drum applications, with the discs being substantially wider at ~7/16" per side. Due to the funky oil seal diameter on the forged GM short spindles, there aren't a lot of rotor options that will work with the same bearing sizes and separation, however since you work at a machine shop, I would suggest that you could either sleeve the spindle pin for a more standard 2.000" oil seal ID or sleeve an alternative hub/rotor to work with your combination. Two potential candidates for you would be the second-gen and third-gen Camaro hub/rotors, both of which would produce a narrower track width than your current rotors. It's important to keep in mind that you're going to be increasing the track width by the hat thickness of the rotors, approximately 1/4" per side for LS1 front discs.

Tobin
KORE3

[Ranaexcavating]

There is a substantial track width difference between the Chevy disc and drum applications, with the discs being substantially wider at ~7/16" per side. Due to the funky oil seal diameter on the forged GM short spindles, there aren't a lot of rotor options that will work with the same bearing sizes and separation, however since you work at a machine shop, I would suggest that you could either sleeve the spindle pin for a more standard 2.000" oil seal ID or sleeve an alternative hub/rotor to work with your combination. Two potential candidates for you would be the second-gen and third-gen Camaro hub/rotors, both of which would produce a narrower track width than your current rotors. It's important to keep in mind that you're going to be increasing the track width by the hat thickness of the rotors, approximately 1/4" per side for LS1 front discs.

Tobin
KORE3

Thanks Tobin

I was under the impression that the standard drum hubs work on the disc spindles. Is this not true? When I searched the seal and bearings i found they were the same for both disc and drum hubs.

[gort69]

Thanks Tobin

I was under the impression that the standard drum hubs work on the disc spindles. Is this not true? When I searched the seal and bearings i found they were the same for both disc and drum hubs.

The standard drum hubs do work on the disc spindles. My car has 69 Nova disc spindles with 68 Camaro drum hubs.

[Ranaexcavating]

The standard drum hubs do work on the disc spindles. My car has 69 Nova disc spindles with 68 Camaro drum hubs.

Thanks Al That's what I thought. Now the only thing I need to find are the drum hubs.

[Apogee]

Thanks Tobin

I was under the impression that the standard drum hubs work on the disc spindles. Is this not true? When I searched the seal and bearings i found they were the same for both disc and drum hubs.

You absolutely can...the seal is a National #8705S with 1.734 ID x 2.405 OD x .235 wide dimensions. Sorry if I confused the issue, as I was just referring to what you had mentioned about cutting down an integral hub/rotor assembly since only the OE rotor is going to have the proper seal counterbore AFAIK. Any alternatives will require some additional machining. The GMSS drum hub and LS1 rotor combination will still narrow your track width by ~1/4" per side versus the OE disc brakes.

Tobin
KORE3

[gort69]

Post a WTB ad here and at Team Camaro - you'll likely find many! As aid - be wary of Pontic hubs.

[Ranaexcavating]

Great! Thanks for everyones help. I think I have located a set of hubs on Team Camaro. Just finished glass beading the calipers getting them ready for paint. The brackets are in the CNC milling center today.

These forums are the best thing since sliced bread!