Project74 said:
I have a 79 w/ a nearly stock 302 (308 in reality) and I want to put different cylinder heads on to improve hp, without going to aluminum. What are the best heads to go with? I've heard everything from 351 to late 60's 289 heads work well.
I have done this to my 79 Capri and my 82 Mustang. I highly recommend the Ford iron GT40 heads. I got one set of SVO new in the boxes from a guy, and one set used from a Lightning truck. Both work great.
I did a valve and seat prep job on both sets prior to installation, and changed the springs on the Lightning set. The SVO set was on the car for under $600, the other set was a couple hundred more.
I would recommend this route, or possible some ported E7's such as Thumpers.
I also did the home port route way earlier, on some 79 style heads. That works, but the chamber volume is still larger than the later or GT 40 units, even milled. Cost wise, if you put bigger valves in, mill them, and change the springs on a stock set, you probably spend the same money as the GT40 or GT40P route would cost and get less performance.
If you go the old 289 or early 351 route, you also may have to mill the rocker bosses, or change studs, get new rockers, and change the springs, etc, etc, for more costs. Note that the newer type accepts bolt down rockers, and the older ones have pressed in studs that need changing and tapping. I have several sets of those around also, and elected not to use them. To me, finding the 351 heads with the bigger valves was also too much trouble.