Can't rev past 4400rpm: what's wrong?

[yelowjaket]

we just got done putting in a new timing chain set on the 302 but i don't know if this is the problem i don't think it is. But i got on the gas today when i was coming home and it was like hitting the rev limiter, got up to 4400-4500 and wouldn't go any further. I usually shift around 5000 rpm's when i'm racing. So i tried from a stop, 1st gear i got it to finally go 5k but 2nd, 3rd, it WOULD NOT go past 4500. So what the heck? I think maybe it's either the valve springs are getting weak and need to be replaced. Or what about the summer heat here in Arizona? could that be a possibility? Not really sure what's going on but i bet it's probably the valve springs because the engine is original and it has close to 180,000 miles on it. Can someone give me any other ideas of what it might be? or is it the valve springs getting old & weak?