1971 340

how did you end up at 425 hp?
Stock 340 in an A body with a gear and a converter would run low 13's and that's only 275 hp.
a 450 hp 340 may not be the best street combination.
Works for me , just need good tires . Daily driver , idles 900 not a problem in traffic never overheats , as of yet , knock wood . Was @ 424 hp before I shaved the heads to make them closed chamber , went from 9.8 to 11.4 compression . Small cam with the 273 1.6 rockers , ede heads and Mahle forged pistons . 3:55 gears 26" tire and a gear vendors overdrive , fun on the street , highway and track . Around $10.00 in gas gets me to the city 48 miles @ 1.42 a litre , sometimes less depending on traffic and weight of foot .