I'm engine dyno testing a 4.0 inch stroke 340 motor with a 4.070 bore (EDITED ) and 10.41 to 1 compression ratio with a Quikfuel 830 CFM black carb with down leg boosters. The heads are a set of eddy RPM and a Eddy Performer Air gap intake. All testing was done with Oregon 92 octane non ethanol pump swill bought this morning. We had to fight ignition and carb. issues this morning so we didn't get to make a lot of pulls today We did make two, first one was from 2500 to 5000 RPM and it made 440 HP at 5000 RPM after running it over 30 minutes total time to break in the cam and lifters. We let it cool down so the oil temps were under 150 F and made the next pull from 3000 RPM to 5500 so we could see If the torque and HP curve crossed at 5250 RPM, which it did On that pull it made 447 HP at 5000 RPM and 459 HP at 5200 RPM with 514 Ft. Lbs. torque at 4300 RPM
I've seen SB Mopar NHRA legal stocker motors take 6 to 12 pulls before they stop gaining power on the dyno
Tomorrow will be a short day testing jetting and timing only, who wants to take a guess at peak torque and peak HP
All guesses welcome, no rewards so no favors
I'll post the results as soon as I can tomorrow evening so bear with me please.