[Jeff Lee]

All points are correct Bill except one item which I don't believe is a factor but to be fair...FWD & trucks allowed cam lift of .430" or OEM lift whichever is greater. FYI: NHRA does not regulate injector size. It is looked at as a carb jet or metering rods; no restrictions.
And when the boost drops due to better airflow you simply increase the boost to compensate. Whala! More power!
All the turbo stocker racers have really missed the boat on consistancy. The "trick" is running a manual trans.

Back to the original topic...If the 350 TPI is 260 HP and the 305's of similar configuration and same class are +/- 2 HP or so, I could EASILY justify a 55 HP increase or nearly 315 HP factored. How? All else being equal except 45 cubic inches. A stocker should EASILY make 1.25 HP per CID...45 x 1.25 = 56 added to present 260 HP = 316. Heck, even a pathetic .75 x 45 = 33 HP. Obviously there is a lot of sand bagging here...