I had some head work done on the number one cylinder as my valve seat cracked and I lost compression. So I brought it to a shop and they did a really great job of repairing and installing a new valve seat. So while I had the head off I figured I'd give it a new set of valves as well. The car runs very well now with the exception of going uphill. It seems to labor a bit and I lose speed now which really wasn't like that before I had the top of the engine dissembled. Flat surface and downhill (of course) it runs like a champ. Any ideas as to why this would be happening?