RustyJC

The corrections are made in the dyno's computer. The operator enters the air temperature and barometric pressure (if the computer doesn't have sensors to get these automatically), and the computer makes the corrections. Ask the dyno operator if the output (HP and torque) is corrected or uncorrected - if it's corrected, ask for the uncorrected readings. I've been told that with some dynos, it's either not available or the operator(s) didn't know how to obtain it.

Let's take the case of a 59 degF (15 degC) and sea level standard day. If the ambient temperature where you dyno is higher than 59 degF and the barometric pressure is lower than assumed sea level pressure (around 14.7 PSIA), then the temperature and elevation corrections factor will be greater than 1, and corrected horsepower will be higher than uncorrected horsepower.

In other words, if you dyno in Denver (5,280 ft elevation) on an 80 degF day, corrected horsepower would be a bunch higher than uncorrected (actual) horsepower.

Rusty

BlackBeast

Well im getting confused still new to the dyno. All I know is so far my dyno guy told me that he does not mess with the results. What ever the computer spits out is what you get. Im sure he adds in what ever your supposed to in the coumputer about humidity or temp or whatever it is. He is very good at what he does. He takes pride in his work he has the most accurate Dyno on the market. Its deffinatly not a forgiving dyno either. Poncis diesel had a dyno event up here this year and from what I understand a lot of people left with low #'s. One guy who was in diesel power challenge with 705 could only turn out around 630. I also know that people I have been talking to who found out my #'s were on a Super Flow win chasis dyno. They were really impressed and told my to get on a dynojet and they wanted to hear what it was after that. They made it seem like I would see a big gain off of switching dynos. I also know this dyno I was on was when I tested I tested in 5th then in 6th and 6th gear is the way to go. Also the load on this dyno is intense not for the light footed or hearted. when he says go and I floor it and the dyno starts the load your just sitting there for like 20 secs then you finally just take off hard. I think the superflow from what it sounds like has the hardest most abrupt load out of all.

RustyJC

And if you don't have any idea what that is, then what......

Rusty

BlackBeast

I have a very good Idea what the computer spits out its in my sig.

RustyJC

So, is it corrected or uncorrected? If it's corrected, what were your uncorrected results?

Rusty

BlackBeast

See thats what im saying I got confused still new to the dyno. My numbers are actual HP the results have not been tampered with in any way. I remember asking him the about the uncorrected vs corrected and all he said was everyone who rolls on his dyno gets what ever the rollers spit out not correcting the results or messing with anything. I got it backwards at first is all. Dyslexia. Yeah thats the coolest thing about the dyno I go to is he never messes with the results so from what your telling me the results on his dyno are allways uncorrected. The other thing is he told me if I hit a dynojet or any other dyno my #'s will be higher. Now he did not say much but he said you could see another 20-30Hp. And like I said earlier Im trying to figure out why some people made a big deal about putting up those #'s on that kind of dyno. 1 person did not believe me. But I got the graphs to prove it.

RustyJC

I'm not telling you that at all. I said:
If the dyno operator doesn't know if the results given by the computer are corrected or uncorrected, I'd find another dyno.

Rusty

BlackBeast

Well no on said the dyno operator did not know. If you read back you realize I told you that He does not mess with the results which would mean there uncorrected. Sorry for not using the right terminology. But just to clarify the HP and TQ are uncorrected. Sorry sometimes I get confused becasue I dont know everything. Actually if you ask people on here about the Dyno I go to some people will probably no about Poncis diesel and the event they put on in Northern California. I go to that same dyno. Still no one has answereed my question about why people make a bigger deal about me putting those #'s up on a superflow compared to a dynojet or mustang.

D.Wiggs

Who are these "people"?

RustyJC

No, that does not mean they're uncorrected. That means the computer spit out some numbers. Now, are those numbers corrected internally within the computer for temperature and altitude? The correction could be automatic if the computer has barometric pressure and temperature sensors at the dyno location. That's what we're trying to figure out. Just because the operator "does not mess with the results" has nothing to do with whether the aforesaid results are corrected or uncorrected.

Rusty

BlackBeast

Well then I guess Im going to have to go ask him. See me not understanding and saying the wrong thing is making me not able to get my point across. All I remember is asking him hey why do People say uncorrected and corrected and he said a corrected # could be anything why would I give you that # its not a real #. Im 99% sure thats what he said. I think its kind of silly we should all dyno on Super Flows with uncorrected # being what is said or posted. But just for the hell of it im going to go talk to him again. The dyno guy like I said takes a lot of pride in the fact he has the most accurate dyno to measure acutual rear wheel HP. So with that said and your explaination on corrected #'s why would he give me a corrected #. HE didnt. Still no one has answered my question on why people made it seem special that I dynoed those #'s on a super flow.People just want to nit pik at the fact that Im not explaining myself correctly because of lack of full dyno knowledge. And "not messing with the results" meaning computer and operator does have everything to do with it. There I said computer to.

C Schomer

Banks' explanation makes sense but I still wonder why the autos had better numbers than the sticks when all of the numbers were from inertia runs and why my constant speed numbers were way better than the inertia numbers. The operator even commented on how quick, crisp and clean (exhaust) mine ran in spite of the low inertia numbers. It doesn't really matter but I'm glad I got to try the constant speed run and see the big difference. I have agree with Banks on the truth of the load dyno. Craig

BlackBeast

Whats the truth on the load dyno.

C Schomer

I mean a constant load or constant speed dyno showing more accurate numbers. When I did the inertia run the egt didn't even get very high so I know it wasn't a very hard load or accurate numbers. But the constant speed run got it up where I expected - like I was pulling my RV up to Eisenhower. Craig

BlackBeast

Yeah I agree the dyno I used is a Super Flow Wyn. It is a load dyno the load is set at around 25% I think. Nothing is factored in but the tire size. This guy earlier got me all confused when we werer talking and all I was trying to say was My dyno guy only factors in the tire size and he puts the 25% load on I think. And I was trying to find out why people made it seem specail that I put those #'s up on a Super Flow Wyn. A bunch of people told me to hit a Dynojet and I would be happy.