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- With the exception of the Boss 351, factory Cleveland rockers are not adjustable. They are positive stop which means the rocker nuts are simply tightened to spec
- Multiple issues can cause lifter clattering; sludged lifters, low oil pressure or worn cam bearings come to mind
- No fuel pressure regulator required for a simple Edelbrock carb swap. The carb is running way too rich which is pretty common. You must get a calibration kit for that carb. It has multiple jets, metering rods and springs. You can download the carburetor manual which will tell you how to calibrate it. For the primaries, subtract the size of the metering rod from the size of the jet. Reducing that difference leans the mixture. Increasing that difference richens the mixture. The secondary just has jets so you would simply install smaller secondary jets to lean the secondary.
- I would strongly suggest swapping the 24" radiator for a 26". This is what came from the factory on big block and A/C equipped Mustangs. You can buy a complete cooling system kit brand new from West Coast Classic Cougar. It has a 26", 3-row radiator, shroud and 7-blade clutch fan. It's not cheap, but it's a lot better than fighting constant cooling issues and it all bolts right in easy peasy. (It's also much easier than going with a custom aluminum radiator and electric fan.) I installed that cooling system on my 1970 Mach 1 with a Cleveland and I'm glad I did.
- I personally find carburetor adapters to be somewhat janky, but they work fine. I would suggest you resolve all other issues and then decide if you want to swap out the intake manifold or simply buy a spreadbore carburetor.
- With the exception of the Boss 351, factory Cleveland rockers are not adjustable. They are positive stop which means the rocker nuts are simply tightened to spec
- Multiple issues can cause lifter clattering; sludged lifters, low oil pressure or worn cam bearings come to mind
- No fuel pressure regulator required for a simple Edelbrock carb swap. The carb is running way too rich which is pretty common. You must get a calibration kit for that carb. It has multiple jets, metering rods and springs. You can download the carburetor manual which will tell you how to calibrate it. For the primaries, subtract the size of the metering rod from the size of the jet. Reducing that difference leans the mixture. Increasing that difference richens the mixture. The secondary just has jets so you would simply install smaller secondary jets to lean the secondary.
- I would strongly suggest swapping the 24" radiator for a 26". This is what came from the factory on big block and A/C equipped Mustangs. You can buy a complete cooling system kit brand new from West Coast Classic Cougar. It has a 26", 3-row radiator, shroud and 7-blade clutch fan. It's not cheap, but it's a lot better than fighting constant cooling issues and it all bolts right in easy peasy. (It's also much easier than going with a custom aluminum radiator and electric fan.) I installed that cooling system on my 1970 Mach 1 with a Cleveland and I'm glad I did.
- I personally find carburetor adapters to be somewhat janky, but they work fine. I would suggest you resolve all other issues and then decide if you want to swap out the intake manifold or simply buy a spreadbore carburetor.
