OST Dyno Day # 3

[zombie]

Omfg

Zombieeeeeeeeee

I Just Remembered Who Phil Is!!!!!!!!!!!!!111111111111

Brown light hair, short tubby, pretty occa ....

hahahahahaha legend ..

yeah sounds about right

[JZA70 R]

up until that dyno day i thought the only time dynos were good for comparing power between cars, is when comparing power between cars run on the same dyno on the same day.

...now i dont even believe that. my faith in chassis dynometers has been reduced to believing that they truely are, purely a tuning tool.

my car was down on power on the day (according to the dyno) ...262 rwhp from a best of 278 rwhp. ..What was wrong with my car? ..i though it was down on boost after i ripped several vacum lines off the plenum in an effort to evade boost cut, but what turned out to be wrong was.... nothing.

nothing was wrong with my car, and what sparked my concern was when Nigel (the turbo A supra) realed off 260 rwhp. 2 hp less than me on only .6 bar. Nigels car runs 100 mph at the drags, mine runs 106 mph. (i hope you guys know the relavence there)

we both took each others cars for a spin after the dyno comp, nigel reported my car felt fast (faster than his) and just to confirm we had a 3rd to 4th gear pull on tonkin hwy on the way home. no surprises what the outcome was.

i would ask peoples opinions on this story but i dont think i want to hear any more theories. ive looked at the dynos data from the printouts and seen crazy differences between intake temps between nigels and my car, and all i can put it down to is the dyno operator combined with the software the dyno runs namely in shootout mode.

for your humour...





its a pretty sad state of affairs when you cant even get a proper comparison of 2 cars on teh same dyno on the same day.

that being said, im a emo fag and my cars gutless lol.

kthnxcyabai.

p.s - a BIG thankyou to Damo for presenting us with this dyno day, Respect for running it so smoothly.
Also congrats to Tristan with the WTF Auto MR2. i loved it how you realised the ebc was left switched off... runs in and switches it on after the first pull and makes like 100hp more for the 2nd. classic.

[glytch]

You might have only 2HP more but look at the delivery dude. At 100Km/hr you have 190HP
He has only 130HP. Its all down to the area under the curve. The different scales on each graph make a mockery of comparing two graphs side by side.

[JZA70 R]

a slightly sharper power band isnt gonna give you 6 mph top end at the end of 400m dood.

[JustCallMeOrlando]

Area under the curve does help MPH dude, especially if you're closer to peak power for longer. As for those intake temps, if that was my graph with the 56 degrees, I would've complained. His engine bay would basically have to have the pod filter sitting above the exhaust manifold to have inlet temps like that.

[glytch]

a slightly sharper power band isnt gonna give you 6 mph top end at the end of 400m dood.

Slightly sharper? It looks that way but not really. You make more power much earlier and peak 30 KPH before he does (though gearing also helps but I cant comment on that. Are they the same gearboxes?)

**EDIT**
FWIW I superimposed the two Boost excluded.

[JustCallMeOrlando]

Oh, and don't forget that 0.9 bar on a 1JZ doesn't equal 0.9 bar on a 7M. Sure the head is more advanced, but the 7M still has half a litre over it. Don't forget that boost pressure is air the engine can't ingest. The peaks will be further apart if inlet temps were consistent as I mentioned earlier, but shit, i'd expect a Turbo A to beat me still, and it's only 30RWHP as is.

[GeneSPIDA]

I'm a novice drag guy (don't take that the wrong way ), but I would have thought the more you make up earlier in a run, the more pronounced the effect on the overall time and terminal speed reached? For example, the better you get off the line and get going, the faster/quicker you'll be. So, if you're car produces power earlier, I would think that could easily account for the higher terminal speed.

Just my 10cents worth

[glytch]

....... For example, the better you get off the line and get going, the faster/quicker you'll be....

I seem to remember you applying the same school of thought to the straights in the MaxAction events and knocking about 5 seconds off your laptime.

[JZA70 R]

with drag racing generally the slower you leave the line the more mph you have at the end.

lower 60' times yeild lower MPH.

you can get a 2.6 60 foot time, wheel spin the first couple of gears and still run a higher MPH than if you got traction.

Same gearboxes btw.

[glytch]

with drag racing generally the slower you leave the line the more mph you have at the end..

For the same ET

[Wildsupra]

with drag racing generally the slower you leave the line the more mph you have at the end.

lower 60' times yeild lower MPH.

you can get a 2.6 60 foot time, wheel spin the first couple of gears and still run a higher MPH than if you got traction.

Same gearboxes btw.

not entirely true man, the reason for low 60times and high mph is normally big turbo applications or high hp cars, because they cant get off the line as quick or suffer lag, but then pull like crazy in a higher gear which results in a faster ET speed.

However if the same high hp car could get off the line quicker it would make an even faster ET speed.. perfect example is Disturbed1's soarer, high hp quick off the line and Farkin quick 1/4mile.

Diff ratio's will also play a part in the side by side 3rd gear pull.

Dyno should be the same as other dyno's in shootout mode, simple, as for air temps, that is down to how engine performs with different temps, maybe one motor was hotter than the other, i know my car makes more power on its second run every time cos it likes to be warm.

It gets very technical with all the things you have mentioned, but need to consider all the relevant factors. Its not as straight up as it may seem.

Matty

[JZA70 R]

it does get very technical matty, which is why it does my head in sometimes.

i dont think it can get any more straight forward running one car after another and comparing the two. its plain to see that our cars make different horsepower in the real world. One makes more than teh other, and the dyno should reflect that regardless of temperature situation. that IS the whole point of shootout mode. to simulate true hp in any condition. hot, cold, low tyre pressure, high ambient temps ect ect.

I think maybe we should run the dyno in a normal mode in future to bar any possible corrections that might fubar figures.

[Wildsupra]

One makes more than teh other, and the dyno should reflect that regardless of temperature situation. that IS the whole point of shootout mode. to simulate true hp in any condition. hot, cold, low tyre pressure, high ambient temps ect ect.

The dyno is set to adjust for these differences, HOWEVER this does not account for the fact that a 7M might like to run at 90degrees and a 1J might like to run at 95degrees, how could the dyno possibly take this into account? it simply cant. To make this comparison easier to understand, it would be like dyno your car on ultimate 98 and making 280hp then replacing the fuel with 91octane and making and making 260hp, it would be simply due to circumstances the dyno has absolute no way of allowing for.

Maybe running the dyno is normal mode would be a goer, but no doubt there will still be people comparing it to shootout mode readings and being happy or un happy with there results.

Am i wrong in assuming that dyno days are just some fun anyways? i would say none of us are out for high hp, more rather out for quick street cars. So as for comparing fast street cars the drags are the true meter (combined with driver skill)

i could just bring the tractor from work if i wanted high hp, pitty its slow as hell though

I hope that makes a bit more sense.

Cheers
Matty

[glytch]

The way I see it. You car makes much more "true" HP. From the start to your peak power you are making up to 65-70HP more at any given speed than Nigel in the same gear.
Its only after you hit your top HP that he starts to catch up. The end number is not what is most important when comparing your two supras.

ie For the entire shaded section your car is faster.