No power on warm engine aka Lawnmower Man

[Travis Goodwin <tgoodwin@xxxx>]

After tracking down all vacuum leaks after the cylinder head repair, I was
ready for a day of smooth sailing. Right out of the garage, the car shot out
like a scalded dog. I was very pleased. However, by the time I was 15
minutes into my journey things got bad. I had no acceleration and eventually
would have to shift down to 3rd just to make up the slight inclines on the
highway. 

I tried disconnected the cold start valve on the way home because I thought
it might be energized all the time, but I had the same result.

I know this problem is temperature related and I'm trying to track down the
culprit. It sounds like it might be a CPR problem, although mine is new.
Could an incorrectly installed vacuum delay valve create this problem? What
else might I look for?