Does it have a round filter on top with no plumbing to bring fresh air from the grill area or does it take in air from the engine compartment? some small (and cheap) gains can be had from cooler air vs. heated air.
The good thing about the headers is it may take alot of work, but not alot of $$$ unless your not doing the work then that might not be your best bet IMO.
A cam may not be too bad an idea just make sure you get one thats right for what you want out of your engine, ie 307CID mostly stock I would think you need more torque in the lower rpm range, like an RV type cam.
I was given a 307, and started to build it, but after alot of research I decieded to leave it alone (just to do me and keep that wonderful smallblock chevy sound) until I got a 350 to build and just put what I want in it as time and money alowed. for about the same price as a stock 307 rebuild, you can rebuild a 350 with mild performance upgrades and be miles ahead in the power/performance area.
without alot of money it is really hard to get alot of performance out of a 307.
hope this helps.
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