header size

[jmoneyfoot]

Looking for suggestions on header tube size and collector length on sbc 145hp 305 with a 2bbl. Any input is greatly appreciated.

[Jack McCarthy]

we ran 1 1/2 on the 283 2bbl back in the day

jack

[dmir55]

With a 4000 stall converter you should run no larger than a 1 1/2 primary tube, a 1 3/8 is better but tough to find unless you make them. Than use a 2 1/8 minor diameter 2 1/2 major diameter collector. These headers would work with the stall r.p.m. recovery point. Hopefully your stall speed and maximum torque are in the same range. We ran a header like this,but with a 4 barrel,with a 302 Ford and ran very well.

[dmir55]

I would like to add something to my above statement. If you do build your own headers, consider fender well headers, There was a reason all those old junior stockers ran them. I would advise you to run a two into one collector, but I think it over scavenge the engine when running a two barrel. Also you can now run any booster. This seems to help two barrel carbs a lot.

[rod]

you should contact Greg at REF in Kingman, AZ. Greg has built 10 sets of 305 headers in the last few months. call him at 928/692-0111.
Rod in AZ

[dmir55]

Building your own headers is not that bad. Buy a kit from someone like Headers by Ed and just go for it. You might never want to build another set, but every racer should try it ounce. You will understand why custom pipes cost so much. But just do it.