problems w the alternator...

I`v just got my car goin after a rebild... but now gor a porblem w the alternator... when i start it gives about 13.8v but fals down to 12.5v when it the engine gets hot....
i`v tryed w a new alternator and it still don`t help... :twisted:

any ideas???

`got a autronic smc, custom e manifoil, t34.........+++


sorry for the bad writing...(from norway)

Are your grounds all hooked up and in good condition?

How's your belt?

my belt is ok.... i think all of the grounds is good.... :|