Lotus 69 FF brake rotor thickness

[4redno]

I'm restoring a 1971 Lotus 69 Formula Ford and wanted to know what the min and max front and rear thickness for vintage Formula Ford brakes are. Is this dictated by rules, original design specs or both?

Please advise.

Thanks...Keith

[Brian]

Cars that had Girling 14lf or lockheed/ AP LD-20 calipers typically used a rotor that was .375" thick new. Cars that used AP LD-19 calipers used rotors that were .280" thick new. There aren't really rules for how thin they can get - people often might use .25" rotors with LD-20's (maybe with pad spacers), for example, to get a bit lighter weight. With LD-19's .180" is probably as low as you would want to go.

Brian

[4redno]

So if I have Girling 14lf brake, what is the Max thickness in pad I can use if my rotors are approximately .350" thick?

Thanks for your assistance.

...Keith

[Brian]

for that you'd have to measure. Probably any off-the-shelf pads for those calipers will fit. FWIW I have aluminium Girling 14LF equivalent calipers on a sports racer, Hawk pads, and .45" rotors. It all fits.

Brian

[M.Sauce]

I have body molds including the tail as well.If you need bodywork give me a call.By the way a Lotus 69 uses Triumph Spitfire front rotors at .310 thick.I stock those as well and just machine them for whatever the application calls for.M.Sauce

[4redno]

Brian, thanks for the info.

Mike, I'm all good for bodywork and rotors.

Best,

Keith