Couple of technical questions for everyone....I have a stock Chevy 283 with the stock heads (haven't taken the valve covers off to see what the casting numbers are just yet) in my 1963 Impala SS. I have a set of heads that someone told me are "2.02" heads. The casting numbers both read "3782461". What I'm trying to figure out is what exactly these heads are and also if I'd see any increase in performance if I took the old stock heads out and put these in.Also, I have a set of exhaust manifolds that the same person told me were "ram's head" manifolds. They are 2 1/2" diameter, as compared the the stock ones which I believe are 1 1/2". I haven't taken the old ones off to verify this, but they look to be about that diameter. Same question as before....I would assume that larger diameter exhaust manifolds would allow the engine to breathe better and increase performance, but wanted to get opinions on this. Obviously, I'd have to change the pipes all the way back to 2 1/2", but assuming I did, would it make a noticeable difference?This is all in an effort to try to get a little more power out of the little 283 with the slug-ass PowerGlide. It chaps my ass that the car is really sluggish off the line in low or drive until it gets up to about 20 MPH...then it goes like a bat out of hell. Very little bottom end and great top end...won't even spin the tires.Any help is appreciated.Aaron
The 2.02 heads are what we used to refer as 'fuelie heads' because of the large size of the valves. These heads were more prone to cracking between the valve than the 1.94 heads, but they add somewhat to your HP. If it was me, I would take them and get them fluxed to see if they are cracked. If they aren't, then get tem reworked and by all means put them on your 283. As for the exhaust manifolds, I really couldn't say without actually seeing them firsthand. Maybe your machine shop could tell you more.