Dyno didnt seem right...thoughts?

Dyno right or wrong, I say someone just over added hp increases on all their mods, If you want a peice of paper that says 750hp, whats your address ill send ya one, I got spare time! other than that, put on the track and lets see some real numbers!!
 
nwpadmax said:
Absolutely not!

What I am saying is, too many people accept the fact that there ARE wide differences between dynos, and many just throw their hands in the air and accept that crappy situation, like it's a random number generator and nothing can be done about it.

I don't accept that crappy situation, and I think there are many ways that we could improve the accuracy and repeatability if we want to take the time to do so.

Would we accept it if all the fuel stations in the country used different weights and measures and calibrations and you never really knew how many gallons you really got? And it changed all the time from day to day and state to state? I think not!

What I'm griping about is the appalling lack of standardization and calibration. I think it can be greatly improved!
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to me it sounded like thats what you were saying maybe just a misunderstandment my apoligies
 
Sledpuller said:
So you are saying it makes perfect sense that one day atruck makes 200HP the next day it makes 800?

I have always thought it was funny, "The dyno was reading low."

Strange you never hear them complain the dyno was "reading high."

You think these PRECISION instruments would give one number-the correct one, not the corrected one, or the uncorrected one.......

Or maybe we just have to accept there really is dozens of 2.6 dayly drivers that are making 1200HP to the wheels....:hehe::hehe:

I love dyno threads!:woohoo:
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:thankyou2:
 
nwpadmax said:
Absolutely not!

What I am saying is, too many people accept the fact that there ARE wide differences between dynos, and many just throw their hands in the air and accept that crappy situation, like it's a random number generator and nothing can be done about it.

I don't accept that crappy situation, and I think there are many ways that we could improve the accuracy and repeatability if we want to take the time to do so.

Would we accept it if all the fuel stations in the country used different weights and measures and calibrations and you never really knew how many gallons you really got? And it changed all the time from day to day and state to state? I think not!

What I'm griping about is the appalling lack of standardization and calibration. I think it can be greatly improved!
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You can preach all day about this, and ultimately you're right--in a perfect world, all dynos would read the same. But, who cares? Find one dyno that works for you and tune your truck accordingly.
 
jlibert said:
You can preach all day about this, and ultimately you're right--in a perfect world, all dynos would read the same. But, who cares? Find one dyno that works for you and tune your truck accordingly.
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:clap::clap::clap:

JP, you are the one who showed me the light on this subject.
 
On the diesels, if you can't simulate street or track conditions, any tuning you do is working off false data. If your truck makes 50 psi and gets to 1800 degrees on the street, you need those same conditions in order to make any worthwhile adjustments. On the Powerstrokes in particular, I can be sure that the programs I'm building for the truck on the dyno are only going to run so hot. You can tune for egts on lower hp tow rigs and send them out the door confident they will only see that temp when towing. I realize that it is a slightly different application than a pulling truck, but the basic principle is the same.

I have a 12v Cummins coming in tomorrow for some tuning. It is a tow vehicle that runs too hot. I will be able to dial everything in on the dyno without ever driving it on the street once. 9 times out of 10 the settings will be spot on the first test drive. There is no way possible to do that on a Dynojet or inertia dyno.[/QUOTE]

Well based on my personal experience that I had getting my truck live tuned on this particular dyno, I would say this is correst. My truck was run 16 times on this dyno while getting pulse width, timing, etc played with along with sevaral different programs for towing, fuel economy, along with a power program for pulling. On the dyno in the power program boost was low 30's, egt's in the 1200-1300 range making only 400 horse. Truck came off the dyno, and was never driven on the street until I left to come home. Made the trip to Westerns test and tune pull yesterday, hooked to the sled twice, boost was right at 30 lbs, egts right at 1250 both hooks. That tells me this dyno is the correct way to dyno a diesel truck simulating a real world condition.
 
jlibert said:
You can preach all day about this, and ultimately you're right--in a perfect world, all dynos would read the same. But, who cares? Find one dyno that works for you and tune your truck accordingly.
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If you're happy with that, good for you, but it seems like a pretty low standard.

I prefer the truth, in this world full of noise and baloney

There is an old quote, I forget who from: "if a little self-deception makes you happy, then so be it."

Another one: "some people, when truth comes knocking at the door, say 'Go away! I'm looking for the truth!'".
 
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People get all wound up on the dyno beacuse they did not make as much boost as they do on the street. So F-in what. More boost by itself is far from a sign of power. If you get the truck on a load cell and load it to get that magic high boost do not be suprised if you dont make more power. Pretty good chance you will not see much difference. Boost as number needs to be compared to drive pressure. This gives you a clue as to how effiecently your turbo is working. Without drive pressure numbers boost is not really a very useful measurement. Most understand that boost is a sign of resitantance. But they think the only the thing that can cause resitantnce is the engine. Which is total crap. The Turbine housing and wheel are very large causes of resitantace(ie, boost) I get such kick out of guys say well John how much boost do you make. I tell them and they say" Heck I make more than that". But they are not making even close to the same power. I run no more boost than what proves to make power. Over boost can cause power loss and turbo death. 45 psi of boost on the same engine with a 2.6" s300 with a 71mm turbine wheel will make a lot less power than that a 2.6" S400 with and 83mm turbine wheel.

Until your on dyno capable of dragging a truck to its knees your going to have a very hard time seeing the entire story. Just because your boxs are on kill and your boost is high does not mean your making power.:rules:
 
nwpadmax said:
If you're happy with that, good for you, but it seems like a pretty low standard.

I prefer the truth, in this world full of noise and baloney

There is an old quote, I forget who from: "if a little self-deception makes you happy, then so be it."

Another one: "some people, when truth comes knocking at the door, say 'Go away! I'm looking for the truth!'".
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And just what is "the truth" old wise one?
 
JOHNBOY said:
People get all wound up on the dyno beacuse they did not make as much boost as they do on the street. So F-in what. More boost by itself is far from a sign of power. If you get the truck on a load cell and load it to get that magic high boost do not be suprised if you dont make more power. Pretty good chance you will not see much difference. Boost as number needs to be compared to drive pressure. This gives you a clue as to how effiecently your turbo is working. Without drive pressure numbers boost is not really a very useful measurement. Most understand that boost is a sign of resitantance. But they think the only the thing that can cause resitantnce is the engine. Which is total crap. The Turbine housing and wheel are very large causes of resitantace(ie, boost) I get such kick out of guys say well John how much boost do you make. I tell them and they say" Heck I make more than that". But they are not making even close to the same power. I run no more boost than what proves to make power. Over boost can cause power loss and turbo death. 45 psi of boost on the same engine with a 2.6" s300 with a 71mm turbine wheel will make a lot less power than that a 2.6" S400 with and 83mm turbine wheel.

Until your on dyno capable of dragging a truck to its knees your going to have a very hard time seeing the entire story. Just because your boxs are on kill and your boost is high does not mean your making power.:rules:
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Well spoken. The dyno I roll on allows me to see the same boost I see on the street, and similar EGT's. Runs on the street are hotter, but also much more prolonged. A dyno run is only a few seconds.
 
JOHNBOY said:
45 psi of boost on the same engine with a 2.6" s300 with a 71mm turbine wheel will make a lot less power than that a 2.6" S400 with and 83mm turbine wheel.
QUOTE]

What about a 79.8 turbine wheel on an s300. 66mm inducer-91.4mm exducer.
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79.8 mm would be the turbine inducer, John was refering to the exducer @ 71mm! Your exhaust wheel should be 80/74, a s400 would be 83/74 but with out the tiny t3 housing of a bullet!
 
05_LLY said:
79.8 mm would be the turbine inducer, John was refering to the exducer @ 71mm! Your exhaust wheel should be 80/74, a s400 would be 83/74 but with out the tiny t3 housing of a bullet!
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You make alot of assumptions...not T3 turbo and not a bullet.
 
Sledpuller said:
Love the youngster posturing!!!!

They were all at the same place-in person-..but SOMEHOW missed seeing each other, NOW on the net they are going to be tough guys.:doh:

HILARIOUS!!!!!!:bang:bang:bang:hehe::hehe::hehe:
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Everyone is a Hard @$$ on the net...
 
SledPuller21 said:
What about a 79.8 turbine wheel on an s300. 66mm inducer-91.4mm exducer.
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It is hard say without having a drive pressure reading to compare to boost. But with that turbine and a T4 foot it may not be that bad. A load cell dyno and a drive pressure gage would tell you lots. If I had guess I would think their maybe some on the table. But only one true way to find out.
 
jlibert said:
And just what is "the truth" old wise one?
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Old, yes. Wise? Only time will tell :D

I'm not sure any of them have reached 100% truth, but the SuperFlow comes pretty close. I've seen my truck repeat within a few % on consecutive runs...and very importantly the curves have the exact same shape every time.

I have yet to hear a complaint about a properly run SuperFlow.
 
nwpadmax said:
Old, yes. Wise? Only time will tell :D

I'm not sure any of them have reached 100% truth, but the SuperFlow comes pretty close. I've seen my truck repeat within a few % on consecutive runs...and very importantly the curves have the exact same shape every time.

I have yet to hear a complaint about a properly run SuperFlow.
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Do you have any experience with dynojets? Brown's Diesel's 248 with semi-heavy rollers is very consistent--Less than 1% difference between runs. any more than 1% difference would be worthless. Your superflow with "A FEW % difference would hardly be considered consistent. That would be over 20 hp on most the trucks owned by members of this forum.

If runs are conducted in the same fashion every time, my truck can hit within 1 hp in three runs. Bring boost up to 10psi, 62-63mph and start the run. Same hp, same curve.

Your experience with dynojets is not consistent with what i've seen them do.
 
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