Thread: 71 Ford truck 460 timing

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Originally Posted by jerry clayton

vacume line is on the correct port for the ford dist. unhook and plug the line when setting the timing- for a 1971 4* btc is listed, 10* for most other years---starting around mid 70s they retarted the camshaft 8* and advancing it back up will help--when they lowered the compression and did all the smog stuff the econ went to hell but advancing the cam, more timing and possibly going to 68 - 70 jets in the primaries will help performance---It isn't a 4 wheel drive is it???

I do agree with the later '70s retarded camshaft in early 460's. It does entail a front of the engine tear down and a new pair of timing gears and new chain - which if it has over 50K miles, probably needs anyhow as the OEM's are 'silent nylon'. From doing that mod to a '76 F250 and a '79 F350, I can assure you that it does make a difference in gas mileage and even better, performance. Set the timing then at 9-10 deg BTDC. Also, trash that bitty 475/525 cfm OEM carb for something that has some venturi area so it can breathe a bit better - the mid to late '70's heads aren't the best

Originally Posted by IC2

I do agree with the later '70s retarded camshaft in early 460's. It does entail a front of the engine tear down and a new pair of timing gears and new chain - which if it has over 50K miles, probably needs anyhow as the OEM's are 'silent nylon'. From doing that mod to a '76 F250 and a '79 F350, I can assure you that it does make a difference in gas mileage and even better, performance. Set the timing then at 9-10 deg BTDC. Also, trash that bitty 475/525 cfm OEM carb for something that has some venturi area so it can breathe a bit better - the mid to late '70's heads aren't the best

The carb is a holley 3310 750 cfm

Originally Posted by hellcruzer

The carb is a holley 3310 750 cfm

...which, of course on a stock engine is too big. My '79 ran with the early 780 cfm version of the 3310 on a 10,000 mile cross country trip and it went from poor gas mileage to beyond horrible. I had several different Holleys on after that, but what ran the best - a 600cfm Edelbrock. I would probably opt for the 650 they sell now instead.

Originally Posted by IC2

...which, of course on a stock engine is too big. My '79 ran with the early 780 cfm version of the 3310 on a 10,000 mile cross country trip and it went from poor gas mileage to beyond horrible. I had several different Holleys on after that, but what ran the best - a 600cfm Edelbrock. I would probably opt for the 650 they sell now instead.

It could be a 780 cfm version. The seller of the pickup told me it could be a 780. How to pump up an old Holley by installing a ProForm carburetor main body, the Proform 67101C? Have you heard anything about this?

I may be way wrong, but doesn't your cam also dictate your timing? My cam card came with specs.