injector builders???

[ja_cain]

I'm going to quote myself from earlier when I said essentially the same thing your buddy did:





The key is using good methods. I've used EVERY major brand of chassis dyno, and most brands of engine dynos, if your test method changes from test to test, so will your results. It's that simple. I'm particularly precise with testing and tuning, to the point that I will make a couple of false starts on a new dyno or with a new vehicle just to determine how the initial sample looks so that I don't generate giant spikes in the data at the start of the test that skew the average numbers.

And I don't hate on any brand of dyno, they all work, some maybe better than others in general, some maybe better than others for specific applications like diesels. The real test for my work has always been results at the track or in one form of competition or another, the dyno is just a tool to measure those results in a controlled environment.


Sent by my right thumb!

Very well put. I think he does all of his diesel testing on the Mustangs but don't quote me on that. Which do you prefer for diesels? Thanks for thought provoking discussion on dynos.

 

[m j]

A change from 15° to 17° is 13.3%. The angle is the stroke. Relative to a 15° pump, a 17° pump will have 13.3% more displacement, regardless of the diameter of the swash plate, because the swash plate in both a 15° and 17° will be the same diameter to work with the same pistons in the same cylinders in the same housings etc. The math only lacks one thing at this point, I still don't have a pump I can dissect, otherwise the pump stroke would be measured, the exact volume would be calculated and your GIGO comment would be answered with hard data and not assumed data. I agree completely that without the physical piston travel measurement, a true volume is not in my hands, but the math itself is solid.


Sent by my right thumb!

the displacement numbers I gave you are from Stealth webpage. you can pull those numbers and see if you can work back to it.
they list 15, 17, and the srp displacements so you could compare what he lists to what you think it should be

 

[IdahoF350]

Very well put. I think he does all of his diesel testing on the Mustangs but don't quote me on that. Which do you prefer for diesels? Thanks for thought provoking discussion on dynos.

For diesels, I had great success with the Dynocom DC-1800XE, and owned one for several years before I stepped back from tuning full time in 2011. I still use the same machine in it's new location when I need to, I also have access to a pretty wide variety of other machines.

The Dynocom has good load control for diesels, this was a feature I helped design and incorporate into the software and firmware of all their load control units. Basically, you can set a base load at steady state to get the turbo to spool up, then as you accelerate the load increases in a very user adjustable real world way, much the same as if you did a 20 to 100mph highway blast.

The problem with the 248C is it's inertia only and thus, a fixed load. So your load does not rise against the engine and it produces impossible acceleration rates for the vehicle if it were compared to the real world. And that's why the readings tend to skew high as well.

Most Mustang installations are the venerable old MD-250, (designated by it's original horsepower capacity rating of 250hp). If you look these days they claim it can test up to 750 or 1000hp. The problem is there isn't enough contact between the tire and the roller to load the vehicle correctly and to avoid melting tires, the reduce the load force, which again allows for an unrealistic acceleration rate compared to the real world.

Dynojet and Mustang machines with load control and 24"-30" rollers are better, but they still have their limitations. And if you enjoy living, there are some other machines that are completely unsuitable for diesel testing, down right dangerous is a better way of putting it.

For the best all around machine I've run diesels on was a 36" Dynocom with a BIG power absorber, it was a monster and could tame anything you through at it. But I've also had some experience with Superflow and Mustang large diameter load machines, and they are suitable for diesels as well.

And getting this back on track a bit, I just need to get my calculations ironed out and that will ultimately decide which injectors and what HPOP I'm going to run. I really want a lot from the combination in flexibility and I'm perfectly willing to go against conventional wisdom a little bit in the process, wouldn't be the first time, and won't be my last.


Sent by my right thumb!