Another slow 340

just my 2 cents you mentioned the things that are slowing it down the spin and the miss if you put the 28 in drag radials you mentioned on you can run a 4.56 rear ratio that should give you a 1.65-1.75 60 ft time and that would compliment your cam and intake combo and take care of the spin you can shift at 6500 but you might go thru the traps at like 6700 or even more. Put the msd box on it and get a tach with a shift light and something I tried with the timing on my car was to wire in a msd retard box like for nos and retard the timing 3 degrees in drive gear and lock the timing and set it as high as it will crank up with(and not ping) but retarding the timing in third gear picked my car up 2 tenths Im running
360 30 over
1.88 port matched j heads
kb flattops zero deck 10.25 comp
eddy performer the smallest one with 318 sized ports matched to heads
crane powermax camIntake Duration at 050 inch Lift 222
Exhaust Duration at 050 inch Lift 234
Duration at 050 inch Lift 222 int./234 exh.
Advertised Intake Duration 278
Advertised Exhaust Duration 290
Advertised Duration 278 int./290 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.467 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.494 in.
Valve Lift with Factory Rocker Arm Ratio 0.467 int./0.494 exh. lift
Lobe Separation (degrees) 114
malory led dist locked at 28
march underdrive pulleys
elec fan
Im running 12.60 at 105 with 4.56 gears and no spin at all thats a 1.74 60 ft a couple other small things dont forget a carb spacer and way more converter if its a strip only Im running a turbo j 4400 converter built for a motor with alot more power and less gear and it stalls at around 3600 and I love it for even my small combo just gotta run a trans cooler dont touch your engine combo other than maybe the carb body to a 750 and just play with the jets
so I say leave the motor except for the carb
go to a 4.56 gear (its an 8 3/4 you can swap back to the 3.23 in 30 minutes to cruise)
go as big as you can stand on the converter
put the big drag radial on it
set the timing
and Im guessing you have a low 12 high 11 second car at sea level if not quicker
keep us posted what you do and what it runs