Leaded,
What I mean by using a larger carb,,,the 2bbl you have might be limiting the air/fuel getting to your engine,,(might be a bit too small) therefore limiting the possibilty of producing more torque.
Sounds like you have no mufflers?
If so,,,sometimes an exhaust system needs a bit of back pressure to produce more torque.
Compression,,,depends on what 307 pistons you have as there are a few 307 pistons that can have 8.3:1 up to 9.5:1 compression roughly w/no cyl head milling.Rough numbers BTW.
You can have more compression w/a 194 cyl head.
There are gear sets (Cloyes)that allows you to advance your camshaft.
Offset wooddrift keys also for your crankshaft.
Lump ports will make more power everywhere.
As far as larger valves,yes a larger valve will help,,,but only up to a certain point,if you install a 194' valve,the torque would drop off in the lower RPM,worse mileage,off throttle response will suffer,but the upper RPM will make more power,stuff you learn by actually testing on a car.
There are IDA manifolds ,Weber downdrafts that would work almost as good as side drafts.
Douglas had them on his normally aspirated Opala,now has 45 MM EFI side draft throttle bodies.
40 MM Dellorto, good carb,that's a small carb,& should be able to get good mileage even w/3, but would need to stay out of the throttle to do so.
MBHD
