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Ok, I understand why there is AT & IT to get rwkw now. So to compare the Optimax & Ultimate dyno sheets of 29 degree's difference in IT my final question i spose would be to what formula is the rwkw worked out from the AT & IT readings or a more simple question to someone with a fair bit of dyno experience, an estimation of how much a 29 degree's IT difference would make to the rwkw.

56 degrees IT sounds realistic to me & if this is my standard temp for my intake when driving my car around, I'm VERY happy with 230 rwkw regardless of a 29 IT temp on the previous optimax dyno sheet.

Thanks for your help Sydneykid & INASNT ia likea to learn :P

I think you should question your tuner as to y there was such a high IT when the AT was alot lower

Well regardless of how hot the intake is *just as long as it actually is the true intake temp* the dyno will spit out the same power right? From what i've learnt *so far...* as long as the AT & IT are true figures the computer will work out the Max power with these statistics with how much power is coming from the wheels going onto the rollers. The good example from you was say doing the dyno run in Antarctica & in the Desert, Very different AT & IT temps, but still would get roughly same power output right? *Even though i automatically think the colder the air, the more power & more rwkw! *koo koo crazy** Can you get a dyno rwkw reading from simply off the rollers. Eg. In Antarctica coz of the freezing air the car made 250 rwkw, but in the Desert, it only made 200 rwkw because of the hot air. Now that makes sense to me. BUT if you use the AT & IT for both dyno runs you'll get the same end results?

So with under the bonnet being pretty hot i think 56 sounds pretty right to me. As sydneykid said, the bonnet was probably open before with the fan pointing at it and bonnet shut on the last dyno run. I will ring up & ask though! Will have to wait till Monday I'd say.

I think you should question your tuner as to y there was such a high IT when the AT was alot lower

With under the bonnet being pretty hot i think 56 sounds pretty right to me. As sydneykid said, the bonnet was probably open before with the fan pointing at it and bonnet shut on the last dyno run. I will ring up & ask though! Will have to wait till Monday I'd say.

As for AT & IT, i dont think im understanding them right yet. I'm not sure how the computer is calculating them to get Maxpower?

Can a dyno work without AT & IT sensors to pick up the power & torque from speed, acceleration, weight off the rollers?

So if the dyno was ran in eg. Antarctica *with no AT & IT sensors* with freezing air, the car might make eg. 250 rwkw, & in the Desert it made 200 rwkw because of the hot air. Now if we use AT & IT sensors in both these situations, then what figures would we get for each situation.

Lets say we did trick the computer. The AT was 25 degrees & we sat the IT sensor around the exhaust manifold & it read 150 degrees while the Real IT temp was actually 40 degrees. The computer then spits out a much higher Max power figure. Why does it spit out a higher power figure? I think im wanting to know how the Max power is calculated from the elements in the equation. Maybe INASNT or Sydneykid could explain it to me if its not too complicated :D

increasing the temperate of the inlet air will decrease power, because the air is less dense, and more prone to detonation.

how shootout mode works is to remove all the "variables", so a desert and antartica run are the same

so when the air temperature increases, the computer calcualtes the effect that the change in temp would have, and adjusts the power readings to suit, ditto humidity etc.

by faking the IT temperature, u make the computer think that the car running in antartica is realy running in the desert, so it will increase the power reading to compensate for the power "lost" from the higher IT temperatures

i tink the power from temp formula was like 3-5deg = 1% power? can't remember

Ok, ok, so shootout is good to get your rwkw regardless of where you are dyno'ing eg. one extreme to another, Antarctica or Desert. But what if i was living somewhere really cold where my car would always have a low AT & IT, I'd actually be making more rwkw than the shootout would display seeing as the shootout takes the "variables" out of the equation. Makes sense now to what it actually does *to what figure it averages the AT & IT down to i dont know*, lets say i was living in dubai or somewhere very hot during the day, i'd also never really be making the rwkw the shootout dyno would be displaying seeing as it would always be a hot intake temperature too.

As i said in Post #23 "Can a dyno work without AT & IT sensors to pick up the power & torque from speed, acceleration, weight off the rollers?" This would then give you the true rwkw in that realtime condition.

Ok so now i know how shootout works...

Yep, that makes sense.  

Optimax, ambient temperature 25 degrees, inlet temperature 29 degrees

Ultimate, ambient temperature 25 degrees, inlet temperature 56 degrees

So as long as the Sensors are in the right places and the AT & IT readings are true I got a geniune rwkw gain. If i had been blowing very hot air into the intake where the IT sensor was *to give say IT 120 degrees*, i'd still get the same Max power reading because Shootout caculates all this.

I rang up this morning, spoke to my tuner, said he didnt even notice the 56 IT, said he must have placed the sensor out of place. Told me how he put the sensor in some 100 degree water once & it only made x amount of difference *cant remember what figure*, said that between my dynos there would be a small kw inaccuracy difference due to the IT temp. I think like only around 3 - 4 kw. It was a free dyno tune for me anyway. I'll probably get another dyno in a few weeks to tune some octane booster into there before i go to the drags with the guys. We'll make sure the IT is right this time & I'll do another dyno sheet post then. They gona lend me some Nitto's too for the runs :rofl:

The tuner is a top bloke, im sure the IT thing was an honest mistake. *Like it was much of a difference anyway.

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