Dyno #'s SAE vs. STD what's the difference?
 

Was looking at 2 different dynojet graphs & mine says SAE (correction factor? the other one says STD?)
Can anyone tell me the difference between the 2?

http://wahiduddin.net/calc/cf.htm

Just google "std vs Sae" and read.... i still dont understand it

So SAE & STD are the same according to that? There has to be a difference
SAE= Society of Automotive Engineers & what they used to make everything a "standard" is that STD? (or is that something you get from unsafe sex?:))

http://www.timskelton.com/lightning/.../dyno_data.htm

According to this STD reads 4% higher

Yeah, there is too much reading for me to comprehend but after skimming some articles STD numbers are numbers that take into account that all variables are constant, like room temp, altitude, outside air temp etc on any given day whether its summer or winter time. Tuners prefer to use STD as it more accurately shows the gains your cars makes from adding XYZ amount of mods. On my chart the dyno room temps were like 95.XX degrees (which was higher than your 59-60 degree temps), at sea level, and mine was done at higher humidity (35% vs. your 20%)

SAE numbers are numbers that are more "realistic" and it takes into account the dyno room temperature, altitude, outside temp, and barometric pressure, which changes daily/seasonally into account. So on a cold day you'd make more power than on a hot day.....


Edit: If someone understands SAE vs STD better than me please feel free to correct me if any of my answers are incorrect.

It doesn't even matter. Just take your runfile, put it in WinPep, and change from SAE to STD to uncorrected or whatever. You can see all the different numbers then.

Simple, SAE is a prediction of what your HP/torque will be at a certain, accepted weather conditon. STD is what your car is actually putting out right at that exact moment.

STD numbers will be higher if the conditions are better than SAE (ie colder, less humid, high pressure), and conversely lower when the conditions are worse than SAE.

So with that said, my graph reads STD which is what the car is putting out at the moment....in horrible conditions, 95.XX degree room temps, high humidity, and average barometric pressure....

So I guess with cooler room temps, like in the 50-60 degree range and lower humidity, like 20-25% I should be making more power :p

Exactly...

this is why comparing STD dyno numbers has NO sense...

To be fair, forced induction by turbo will throw havoc when trying to use SAE ratings, especially if you're at altitude. A turbo will simply spin faster to overcome the lack of boost, thus partially negating the altitude's thinner air.

When you look at some of the STD and SAE numbers of those cars dynoing at altitude (3000+ ft), the SAE conversion looks absurd and is not very accurate at all.

Are you guys sure that STD shows actual numbers? I thought that's what uncorrected does - it shows EXACTLY what you put down without any correction. STD actually is a correction, so I don't see how it could show "actual" numbers. Plus, uncorrected is almost always different from STD.

Case in point...here's my 500' vs 5500' SAE numbers a few months apart with the same mods. Notice how I somehow gained 36whp/53wtq by moving a mile higher in altitude - SAE is very inaccurate for turbo'd cars:

http://i22.photobucket.com/albums/b3...s_5300_SAE.jpg

SAE and STD correction are just that......corrections. The only uncorrected setting is "uncorrected". You see, there are many many correction settings.... DIN, SAE, STD...ect. The only true uncorrected setting is "uncorrected". Also, smoothing to 0 helps you actual numbers as well. When you have no smoothing, you can see the actual torque measured by the dynometer.

You are correct about everyhing else. For instance, uncorrected will be higher than SAE or STD if conditions are better than these correction factors, if conditions are worse, uncorrected will read lower.

CJ

Learned something new......always thought STD= uncorrected......sorry for the misinfo.

it's cool. You where on the right path, just had STD and Uncorrected confused.....

Correction factors can be a bit confusing.

CJ

And misleading...