I just put a rebuilt 305 in my car from an 81 chevy van. Installed comp cam 268ex.(Did research and most of you guys think that is too much) Rpm performance manifold, elederbrock(sp) 600. Hedman header(no mufflers or cats yet). The car has posi 3:42, t-5. Set timing at 6 and 8 btdc didnt seem to change anything. If you have anything I should look for it would help. I will be working on it this weekend. Any idea's are fine, If I did over cam this motor shouldn't it still run half way decent? Thanks for any and all help.