K, according to the article he wrote about this engine, it was 140+ at 2050 engine rpm, on an engine cell dyno. Ok, I will finally say its 140hp,, AT,,, 2050 rpm. Rated rpm, for tractors, is a governed speed, set by the tractor makers. Nebraska testing used 540 or 535 pto dyno speed to check for the HP for that make and model of TRACTOR. Whatever the engine rpm is, the tests were done at 540 or 535. I guess in other words,, thats tractor mechanic lingo, because, back then, thats all they had to go by. For me as a Tractor mechanic, I must follow suit and still base all my research off of the same path, our founding fathers had done so many times 50+ years ago. 540 pto. Im playing with tractors, and engines so I dont have the luxury of only using one. Im just following suit. Im not blind to more modern methods though,,,,, , I have a stack of Hot Rod magazines 2 feet thick, and everyone of em has some sort of article of an engine build up,, more power!! More power!! read all about it. They take the engine out of a SS Chevelle, or a Hemi Mopar, and they put on the engine dyno,, and they tune it, dial it all in, record the numbers for the highest readings, and that becomes public knowledge,, or bragging rights,,, Right? Then the owner of said machines, put that engine in a car, truck or whatever,, then, they decide to put the whole car on a chassis dyno, to test power at the rear wheels..... ... Well, Im a fan of the powerblock shows on Spike TV,,, and I see that show called HP TV,,, They have one of these chassis dyno testers. Ive heard that guy say time and time again, the engine would be alot stronger in HP results, if it was not going thru the drivetrain. So, does that mean that there is not said HP going thru the wheels???? Not thru the wheels,, no, at the crank yes,,, and the beaty of that statment, is that they choose the rpm varying ranges,,, not set by a governor. You asked me if the engine made 140 hp atthe crank, is it present at the pto, or wheels,,, Yes, and NO. The yes part of the argument is,, at 2050 rpm the engine made 140+ hp. But, what is it at rated tractor rpms?? 1720 rpm is for a wd, and 1995 is for the 17. No question in my mind, at 2050 engine rpms, turn on the pto,, at 643 pto rpms, it would be 140 hp, if a pto dyno would show that without the card conversions. No Tractor dyno will let you do that, without the card sheet conversion,,,, So here comes the NO part of the argument,,,,, Tractor chassis are set for a specific rpm range for 540 pto speed. Unless, you regear the pto to run slower,, you cant get away from 540 and the set engine rpm. Since we are talking about a Pulling TRACTOR,, the stock chassis had a pto at some time in its life. So a 540 reading, sometimes is all we have to go by, and the proof of that is, whats available,,, tractor dyno's are bout on every street corner repair shop, so,,, back it up and hook on. Reguardless of what the engine dyno says,, the pto dyno is going to tell the story of what it is in tractor terms. The pto dyno, in my opinion works in opposite of what an engine dyno works. One, the pto dyno reads hp higher as rpm drop, anything above 540 is irrelivant in tractor terms becuase without the cheat sheet conversion to read higher rpm ranges. The pto dyno does not read it. 540 is where the tractor dyno test is read at. Two,,, the tractor dyno, does not care what the HP is at 2050, its not capale of reading that rpm,, unless thats what the engine rpm is at 540. , but it will be a lesser reading,, the 540 hp reading will always be higher that 550, 600, 675. 540 and below, the HP numbers go up higher than what it would read at 675 or what ever 2050 was,,,, So, according to the pto dyno,,, the lower the rpm, the stronger the engine. What do I know, using tractor terms?? Simple, I took real world knowledge,, 140 hp at 2050, and converted it to if was read at 1720. I told you already what I belived it would be,, only thing i did was slow that engine rpm down to real tractor terms. 117.46 hp at 1720 or 540. If it was 140 hp at 2050, the pto dyno will be a lower reading everytime. its not that the 140hp is not present,, but its not present at stock rpm,, at least according to a tractor dyno. its there when it hits 2050,, but not at 1720. Thats just the way it is in the tractor terms. Thats all Im saying. I appreciate the time and effort your doing to help me understand what your talking about. Trust me, I know what your saying, but, understand,, even though we do what we do to tune the engine, as far as what to do is the same, the two dyno's will read differently everytime. its something your gonna have to trust me on,,,,, , if you want proof of my theory,,, if anyone has an engine dyno setup to dyno a IH H,, Ill be more than happy to bring my engine to a engine dyno cell,, read HP at 1815, and what ever rpm range im allowed to run,, or what ever rpm range the best HP was made at. then, we will put the engine in the chassis, and run a pto dyno tractor terms test. I promise you, if the Best HP was made at a higher rpm other than my rated rpms,, it will show less everytime if its pulled down to 540. See, its more of a trick to keep tractor builders honest, because we can check the work,,, we do say you get x amount of HP at 540,,, and trust me, they check em,,, using that pto can keep em all in a line,,,, Using the other dyno,, even though its not a tractor terms hp test,, its a way to break away from the pto hp estimates given by quote, or promise,, but if the buyer was smart,, thed ask for the HP to be checked at tractor rated speeds. or simply state,, they dyno the engine by itself and go by that. its the customers choice at that point,,, but we keep it the old fashoined way,, keep it real, keep it tractor,, keep it honest. Its up to the builders discretion on how they report their HP, and if they know there is a difference in the readings,, they should report it. LW done just that when he dynoed project M,,, he said his water brake dyno will be different from a HYD fluid dyno. I have no problems with any technology that follows engine only dyno tuning,, but when they try to pass it off as tractor hp,, its not even tractor related. I know, Ive said this over and over,,, and over,,, but, there is a difference. Now, if you want to explain the differences, pick an engine and go with it,, I have a H I love to show the pto dyno and the engine dyno difference. Id like to know what peak hp I can really get at 2500rpm out of it. How do I do that, and is 150 hp possible out of a H?? Ive seen 130 on a pto dyno from that H,,, sooo,, what would it be at 2500? Then, my bragging rights shoot up even higher. Hope I did not tick you off here,, its a trick all us farmers/tractor mechanics use to keep the big money builders in an honest hp quote. Trust me, your not the only one Ive showed this to,,, my machinist buddy did not know either till I showed him. Hope to get into some good discussions on this new tech,,,, Im just old fashioned, but a younger fella. Chad
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