340 on pump gas

I agree with the aftermarket heads I have a 67 cuda with 340 mp .557 solid cam j heads and some bowl port work. best et has been 11.7's pretty much your combo and the car works great. I could write a page here on whats been done. Should have done w-2 or edelbrock heads was my only mistake!!! I would go with the M-1 intake edelbrock heads, .555-.590 solid cam, 850 carb or go E-85. Make sure you get the large tube headers they make a tenth - tenth/half over 1 5/8 that wrap around steering when you start making steam! Everyone is right on don't cheap out on the convert. Match to your combo but from my exp. go 3-400 higher than what they recomend they seem to be a bit to tight for me everytime.