Getting power out of a 63 /6?

805moparkid said
this can go either way depending on how you do it... if you throw parts together and hope for the best then yes, hp+ mph down...

MPG is directly connected to VE, volumetric efficiency...

slants with there poor cyl head and compression is a great place to start...

a slight port job to increase the amount of A/F charge will help increase power. now becasue of your new increase of power you can get better MPG becasue it takes less fuel for the same volume becasue it is more effecient...

my slant with a 600cfm Mechincal secondary carb, 246 degree duration @ .050 with 10:1 comp. and a 3500 stall converter/3.91 gears get 20mpg. did it to vegas and back...

you have to build a combo for the best VE and make sure when it is operating it is in that area of highest VE.

as far as carbs a mech secondary carb can get better MPG if you can keep your foot out of it. you dont have to change a spring so it will open later for MPG, or sooner for power... with a mech secondary carb you dont have to worry about the secondaries opening unless you tell it to...

so use the 390, probably skip on the headers, you will lose heat thru the headers unlike a stock manifold... get it to 9.1:1 -9.5:1 compression and give the head a nice work over...

I was going by the OP's original definition of his engine as "bone stock" and that MPG was important to him. Bolting on headers and a 4bbl won't help either HP or MPG in my opinion. I would add the better air intake to my list so it receives a colder air charge but as Mike and Dan pointed out, you can get one off any later Mopar and adapt it rather than spending big bucks for some whiz bang aftermarket system. Put the money saved into a rebuild fund for the engine where you can do more serious mods as you suggest.