Can I take this Mustang?

Agent_4573-
"how much more power will a 306 make than a 302 with everything else the same(intake,heads,cam, etc)"

You said that the other stang had a rebuilt 306 w/ GT-40 heads. Those are not like your stock heads. Even with the stock cam & manifold (not sure why didn't complete the package?) he's making more power than you...plus he has a 5spd. So it sounds like the motor is fairly new and healthy, regardless of the condition of the rest of the car...sorry to say, it's going to be faster than your stang.

You should try to find some aftermarket cylinder heads & a cam, to take advantage of that intake! Then you'll pick up some real power. Let us know how it turns out if you guys run 'em!