injector builders???
- Thread starter 99powerstroke7.3
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IdahoF350
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So you're implying the 175/80s he claimed made 490hp weren't 175/80s, and that they were larger? Maybe 175/100s, or 185/xx? Where are you trying to take this? Maybe they were 175/80s on a truck with more than enough pump to push them to their limit? Or maybe it was a scary tune that would make the bottom end crap itself on the street and it was a Hail Mary dyno pull? Is it that hard for you to fathom that that injector is capable of that number? How much data do you really need?
I get being skeptical but you're practically on a witch hunt over a reputable injector builder's claim.
We're on the same page there, I know that without ALL the supporting mods none of those big numbers are attainable. I've been telling guys that for the past 15 years when they come to me for their go fast fix. I also know that well within the operating limits of the forged 7.3 engines, say 400-500hp, this is a highly relevant discussion.
At this point, without anyone seeming to have ever divulged the displacement I the stock HPOP, and do data on the drive ratio from the crank to the pump, I'd like to get my hands on a scrap 7.3, just to calculate the drive ratio and then to disassemble and calculate the volume of the HPOP.
It's pretty easy to calculate the approximate volume of oil required by the injectors based off of their rated volume. If the builder would divulge the true volume of the injector OR a maximum safe volume for the injector to deliver once you had a pump volume vs speed charted, you could pretty closely figure out the required IPR duty cycle for any combination and know where injector volume demand exceeds available volume from the pump and IPR combination.
At this point, with the data I've got at my disposal (which isn't much) my calcs put AD codes needing 8400cc of oil to deliver their full volume. If the 15° pump was changed to the 17° pump to keep the duty cycle on the IPR under 65%, then we know that 65% of the volume of the 15° pump is less than 8400cc. So if the maximum demand stock is at HP peak which is 2800rpm, then we know a 15° pump is less than 8400cc at 65% IPR at 2800rpm. That puts the 15° HPOP volume at just under 13000cc at 2800rpm. And by the sheet nature of the design, the change to 17° from 15° is 13.3% more stroke on the pistons, and that would equal a 13.3% increase in volume to just under 15000cc. So an aftermarket pump claiming 30% more volume than a 17° pump would be close to 19500cc.
Dial that backwards into injector size, and that big single pump has the volume for a 300cc hybrid or a 225cc A-code running 65% duty cycle. A standard 17° pump will be on the edge at 65% IPR duty cycle to run a 175cc A-code, but ramping the IPR duty cycle up to 85% or putting it on the edge at 90%, should result in having more than enough oil for 175/80s. The IPR is, after all, just controlling the flow of "wasted HP oil", so why waste it.
The deeper I dig into this, the more potential I see lying around in the tuning and the details. And that's not to make light of what's been accomplished by anyone else, or blast conventional 7.3 wisdom as wrong, just maybe that there is a little more left on the table that even the most accomplished tuners and builders have left on the table because try have otherwise already reached the goals they set for themselves.
Sent by my right thumb!
V-Ref
Active member
There's been no data published by PIS to back up the 500 hp A code 175/80 other than the 490 hp Dyno run. And I'm pretty sure most would agree that a Dyno is a tuning tool, and not a great power metric unless it's a 248c or known/reputable dyno.
The thing I'm most interested in is the "data from our testing" quote about how A codes have been outperforming hybrids for yeeeeaaaarrrrrsss in his experience. ...so i asked for a flow data sheet.....that's all.
No witch hunt. Just want to see the flow data sheet that's led him to this conclusion was all.
The thing I'm most interested in is the "data from our testing" quote about how A codes have been outperforming hybrids for yeeeeaaaarrrrrsss in his experience. ...so i asked for a flow data sheet.....that's all.
No witch hunt. Just want to see the flow data sheet that's led him to this conclusion was all.
V-Ref
Active member
Thanks for posting that. Is this the Acode or the hybrid?
m j
Active member
pump size and drive ratios are easy to find
camshaft is 1:2 so all you need to do is count teeth on the gears
ja_cain
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They only have the 175/80 a code listed on their site, so I assume that is what he is referring to.
IdahoF350
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Any dyno is fine if it's the only dyno used throughout the entire testing process, be it multiple vehicles or one long term project. My experience with them is pretty in depth, both because I've been using them since the late '90s and also because I worked as a consultant for nine years and as a technical advisor for two years for a dyno manufacturer. They are just like computers, garbage in, garbage out. And I've run everything from 6 second door slammers to a 5 year old on a bicycle, you can test anything with repeatable accuracy if you use good methods. DynoJet 248C is solid and repeatable, but they read high, always have, so if that's your standard, that's cool, but don't compare a pull on a DJ-248C to a MD-250 or a DC-1800, the results are less comparable.
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IdahoF350
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So the HPOP is driven at 84.4% of crankshaft speed. But I'm coming up at the pump not needing to be that large, actually more like 5.5-6.2cc. If a 15 degree pump is 6.8, a 17 degree would need to be closer to 7.7cc due to the change in stroke. It makes more sense if that the range for a 17 at 6.8 to 7.2, then a 15 would be in the range of 6.0 to 6.4cc. Just need a real number. May have to round up a scrap pump.
How is output on a 248c able to be.manipulated at all? There is no variables.
lincolnlocker
Well-known member
I have no idea what the data is on my 170/100 casserly inj but it has done anywhere from 403 to 492hp on 3 different dynos.. track et puts it at 450hp in 4x4 and mph puts it at 470hp in 2wd... I wasnt sure if you where saying its not possible to hit that high of hp with small injectors or not..
live life full throttle
IdahoF350
New member
It's not, at least not by the operator, unless you know how to monkey with the weather station in the stack :shocked:. But in the 15 years I've been on engine and chassis dynos, I've had far too many cases of chassis dynos reading impossibly high numbers, DynoJets included.
First time Ive ever heard that...its considered the gold standard by maaaaany.
V-Ref
Active member
What he's saying by manipulating the temp & pressure altitude/absolute pressure parameters, the correction factor can jack the corrected numbers outa whack. Technically speaking
But an uncorrected 248c number......as long as tire size or eng rpm/is synced up with roller rpm...that's a pretty good number IMHO...I think even Idaho would agree there
What he's saying by manipulating the temp & pressure altitude/absolute pressure parameters, the correction factor can jack the corrected numbers outa whack. Technically speaking
But an uncorrected 248c number......as long as tire size or eng rpm/is synced up with roller rpm...that's a pretty good number IMHO...I think even Idaho would agree there
Thats what I.was getting at. I.didnt know you could. I thought it.was a strap it down and go.affair.
ja_cain
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I am not going to even try to bull****e that I know anything about dynos, but I just talked to my buddy who works at Afton Chemical and they have over 20 different chassis dynos at his site. He said his mustang dynos are very consistent (even if he has the vehicle offset left or right) and they run the same vehicles on them on a weekly basis. Some of the dynos he operates are even all wheel drive units and they have tested twin turbo Corvettes 6 gear up to 208 mph on them. He is going to get me actual model numbers if he thinks about it. I'll ask him to comment on the different models when he does that.
ja_cain
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Gotta respect the Tang
m j
Active member
I dont see what you are basing your math on, looks like GIGO.
in order to know the change in stroke you would need to know the diameter of the swash plate wouldnt you?
you could probably figure it out going backwards as you know the number of cylinders is 7 and the bore is .437
IdahoF350
New member
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!
IdahoF350
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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!
