Doug Axelrod's Dyno Chart??

[Bob In Ct]

I was recently looking at a Dyno Chart in the random gallery produced by Doug Axelrod. Can anyone out there explain to me how the torque and HP lines cross at 4,300 RPM?

I'm no Bob Putnam, but I'm pretty sure that the HP /
torque lines by definition cross at 5,252 RPM.

Doug, is it time to find another dyno shop?

Bob

[George Snyder]

Bob,
You are correct. I have been told many times that the following imformation is true. Always!

HP = 25% of torque @ 1,300 RPMS
HP = 50% of torque @ 2,600 RPMS
HP = 75% of torque @ 3,900 RPMS
HP = 100% of torque @ 5,252 RPMS

[Doug Axelrod]

Gentlemen (and I give you benefit of the doubt here rather than assuming that you're just being mean-spirited):

Before you impugn my (superb) engine builder's competencies, I suggest you read the axes on the graph. I'd be happy to provide a tabular form, if you require.

NB: This engine is no more, as I replaced the cam with a hydraulic roller cam of very similar cut. Runs slightly stronger and sounds more percussive. I suspect the power is quite similar, but have no interest in disinterring the motor for another stand test.

Doug

[Bob In Ct]

Hey Doug:
I guess I'm missing something! What I do know is that (using english units) HP = (Torque * RPM) / 5252. That is not my personal formula, that's the way it's done.

Based on this formula the HP line will always be below the torque line when RPM is below 5,252, and above the torque line when the RPM is above 5,252.

I'm not giving you or your engine builder a hard time. Please explain to me the part I have missed.

Bob

[Curt C.]

Sometimes in order to better accomodate the information, the axis are different. For example, the HP axis will range from 200 - 500 and TQ axis will range from 300 - 600. Hence, HP and TQ actually do intersect at the proper point, but not in such an altered presentation. I have not seen this particuar dyno graph, but many like the one you have described. Study the axis and you should see this is apparent.

[Excaliber]

Yup,,,,What Curt C. said! It all depends on the format you use to DISPLAY or GRAPH the data.

Doug,,,,LOL,,,a "superb" response.

Ernie

[Bob In Ct]

Curt:
It's clear to me now! The numbers are a little small on my screen.

Thanks, bob