The dyno here is a 1997 vintage 901.
When it was ordered then, the boost valve was an option.
The dyno shop I worked at in the early 90’s had a 1986 sf-901...... and that one didn’t have the boost valve.

The prime solenoid has a very small pathway through it, and gets clogged somewhat easily.

I don’t think it acted up on this one until it was about 12 years old.
I took it apart, cleaned it out..... and it worked fine for several more years.
I’ve done it once or twice more since then, and it needs to be done again.

Opening the boost valve on this dyno makes a very noticeable difference on how low you can pull the big tq/low rpm combos.

I almost never need to use it for the typical stuff I build.

I’ll see what we have for sheets with high tq/low-ish rpm.

The only thing I have handy is a mild 505 from a few years ago..... which was 592tq@3200....... and I didn’t use the boost for that motor.



I know we’d be able to do that here with that motor........ and likely without the boost.

As it turns out I do have a run here from a 572 wedge street motor with EZ 295’s on it, and about 10* more cam than your Hemi build........ from 3800-6100.
This run is with an ootb 337 intake and a Mighty Demon 850 carb, and my dyno headers.
Those are 2 - 2 1/8 x 4, so they’re not helping the numbers down near the bottom.
By 3800, the absorber is pretty happy...... so this is no problem at all.


The real high tq/lower rpm stuff would be something for a boat with a roots blower on it....... and I dont have any of those sheets here.
But I’ll see if I can dig something up.

One last thing....... and forgive the dumb question....... but I’m going to ask it anyway.......

You have adjusted the capacity valve...... right?