Stalls out 45-50 MPH uphill?

1976 JEEP CJ7
94,000 MILES • 4.2L • 6 CYL • 4WD • AUTOMATIC
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DONUTOLYMPIAN
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  • 3 POSTS
Okay, so first let's cover what I've done to the vehicle:

HEI distributor
New mechanical fuel pump
New fuel filter
Weber 38/38 carburetor

So, all that said, it cranks up great, runs great up to 30ish MPH.

Every time I go uphill (sometimes when on level ground) at 45ish MPH the engine starts sputtering and stalling, lunging and slows down.

I've got no idea what to do to fix this, I'm pretty much out of ideas. It's got fire, fuel, and air without issue but uphill it suddenly acts like it doesn't.
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Mar 28, 2023 at 7:28 AM
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DONUTOLYMPIAN
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Not sure why the pics are upside down, they appear right side up on my phone, sorry.
Mar 29, 2023 at 5:09 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,256 POSTS
No problem, I have seen the fuel line going to the tank develop a small hole or crack which allows air to engine the suction side of the pump which allows the fuel delivery to be limited. I would replace this fuel line which should take care of the problem.
Mar 29, 2023 at 5:16 AM
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DONUTOLYMPIAN
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Awesome, thanks for the response I'll check it out!
Mar 29, 2023 at 7:01 AM
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