running out of breath in the 1/4 mile

Why are you asking the same questions repeatedly when they have been answered? You've already been told at least once because I answered you that the 3/8 line is not necessary........BUT it would be ok to go to it for future upgrades. Beating on the same questions just to get a different answer is wasting time that you could be fixin the thing.

I am beginning to think all you want is to hear the answers you are looking for.

Your car has a 408 stroker. You're talking about racing it on the strip. No way in HELL would I ever use a mechanical pump, but you seem dead set on just that. I don't give a rip how many say they've used them. The electric pump is the way to go.

Here's what I would do if it was mine. Throw that mechanical POS pump in the ditch. Replace it with a block off plate. Run new 3/8 line from get to go, "just because".

Pick out a GOOD electric pump. Mount it as CLOSE to the tank AS POSSIBLE. Pumps are made to push, not pull........even mechanical pumps. This is why they are at a HUGE disadvantage. When mechanical pumps are in stock to fairly mild applications, they work pretty good. But when you ask them to be in a REAL performance application, they can fall short.

You are experiencing CLASSIC fuel shortage symptoms. That's been suggested several times. Go to the strip. Look what people run that have similar engines and drive trains.

Take the advice and keep using a mechanical pump. You will keep having problems.