69' 250 stalling in higher gears...abruptly.

[ViviensTractor5110]

Good evening gentlemen. I am new to the forum, though have long lurked and gleaned much valuable info from you all. Thank you.

So...I've been wailing away on my 69 for a few months now...recently got it started and am experiencing an abrupt die out after short distances of driving...most regularly when I hit fourth gear.

It is a 250/1bl rochester/ sm465/ 307s

Carb is clean and squirts when it's supposed to...so accelerator pump looks outwardly ok...plenty of fuel to the pump...fresh fuel...does have an inline filter at the carb inlet...new. Starts on the second rev. Idles well.

Any insight from your experience is appreciated.

Thanks
Travis