The reason people are discouraging you from building a high horsepower 302 is because in a 5000-6000lb truck the usefull powerband is gonna be 3000-6000rpm. With the right axle gearing it'll get the job done but it's not gonna get anything that could be confused with gas milage. There is no way to get big low rpm torque from this motor there's just not enough displacement, so a more realistic target for typical truck use would be 300hp from a 351 or 351 based stroker. That is doable on a budget because it doesn't require an expensive aftermarket topend, just some GT40s, a cam, longtube headers, a fresh bottom end, and you can keep the factory EFI and overdrive transmission if so equipped so despite the larger displacement it will still get reasonable fuel milage.

 

what is reasonable fuel mileage lol

 

Conanski, I agree. In our heavy trucks the torque that a 351 and set up you describe is. For me the way I would go.

 

Mid teens, the engine proposed here will never break out of single digits.. may as well have a 460.

 

Just crossed my mind, would any of you guys happen to know if the bell housings sets are the same on the 302 as a 351w? It's a manual but Im not sure what model it is.

 

Yes bell housing is the same..

 

The 5 speed in my '89 F250 with 302 engine is the M5OD and I'm a little hesitant to put a stock 351W (which I have) in it, let alone a high HP engine. If it is an M5OD in yours you will probably need a different trans. because the M5OD is not strong enough.