trying to pull ponnies with little cash

If your running the original 7 1/4 rear it most likely has 2.76 gearing. It's not going to be a tire burner even with 400 HP with those gears. I would change the rear end first and then start with some bolt on parts. You can add 100 HP to a stock 318 with bolt on parts using stock heads. 300 HP is easy to come by 400 will take better heads or head work and a larger cam.

the car was originaly a 4spd so it probaly is a 2.76. i wish it wasnt converted to auto but it kinda worked out good for me cuz i rebuilt a 727 to get rid of the slippin 904. i do plan on power steering just for easier cruising. when it comes to exhaust im going to run the same size as collect all the back with super 44s. im suprised i havent got pulled over yet with the glass packs cause its loud now. as for rear end im sayin a 9 1/4 or dana 44 only cause i have those to on my property already i would do 8 3/4 just difficult to find one here and ive heard horror stories with small horse power to them. (sorry i tend to jump round but atleast everyone knows what im talking about)