Alright, I would like to swap engines in my camaro RS. Stock engine/trans. = 305 TBI w/ 700 R4. I would like to drop in a 350 and hopefully achieve 300 horses with reasonable gas mileage. I feel comfortable around carbs, but not too keen on TPI systems. I don't know enough about them I guess is what I'm saying. How hard would be to drop in a hefty bottom end 350( slightly bored, mild cam), and intergate a TPI system from a 90-92 IROC? Would the stock TPI system be enough to fuel the engine up to 300 horses? Could you go more with the stock system? Also concerned with the prom burning part??? No clue there.... Big question here is I guess is, How much better is a TPI on gas mileage than a properly tuned carb?

 

Overall, the TPI is going to win the gas mileage war. You might get a carb to do as well under certain conditions, but it won't keep up under average, real-world conditions.

I had mine on the road last weekend, return trip this weekend. I averaged 22.4 MPG the 1st tank, and 24.2 MPG the 2nd. Not too bad, I think, with a low-13's car with 2.93 gears. I get about 17-18 MPG commuting, depends upon how much "fun" I've had on a particular tankful. This is a computer controlled carb, some have reported very respectible #'s with non-CC q-jets, but computerized will tend to do better than mechanical non-feedback.

TPI will need significant modification to produce 300 HP (depending upon your measurement method - less modification for 300 gross flywheel horsepower than 300 rear wheel horsepower). The cost of those modifications (base, runners primarily) will take quite awhile to pay back.

Which is "better" is really your choice.

 

300 at the wheels or at the crank?????