Starts out good for the first few lines, then falls on its face.

It’s down 75-100 tq & hp(if running adequately sized headers)

Is it the dyno or the induction?
Or something else altogether?

It’s not using much fuel...... which kinda goes along with the low output.

Here’s a 505, Stage 1 RPM heads, 252/260-112 SFT caml, 2-2 1/8 headers...... also a 6bbl on an Ede manifold.

From 5000-up, the fuel flow was 240’s-250’s-260’s..... with it topping out at 266@6000.
It was in the 220’s by 4700(you’re barely over 220@5700).