Just re wired my 305, everything working perfect except on ignition and crank it revs to the absolute moon, doesnt stop unless car is turnd off.
Has fuel pressure, all 12v connections, has pcv and break booster hose connected but only those.
Timing sounds to be pretty spot on felt for combustion stroke and stopped as soon as the piston paused.

the distributors vaccum hose was plugged at first and still same results, connected that one and no change. It has a Summit Racing™ M2008 Series Carburetors SUM-M08600VS carb on it.

any help troubke shooting would be great thanks. Only know about LS engines and EFI so this is super new to me

 

you have a vacuum leak and probably a fuel system issue.

I know a lot of people that have issues with the summit branded carbs.

step 1 - get your hands on a known good carb.
step 2, get a timing light. your SBC should be timed to ~8 to 10 degrees BTDC.