DivineE

Excellent information thank you v.much for that response. I do know what you mean about being able to hang on to a gear when you're really going for it. Now go on, you know you want to splash out on a video camera so we can see that return to the track

asiancaucasian

Here's one of the runs from yesterday. Not sure what happened to the AFR for this one. When I get the other chart with the torque I'll post it up.

TurboTommy

Because, it's a chassis dyno chart. They're very inconsistant for obtaining power readings and can pretty much made to be read whatever you want them to read; and it doesn't cease to amaze me how people continue to hail them as gospel.
Just can't bite my tongue.
That engine/mods combo can't make that power (real power which is on the same scale as a 247 bhp turbo S).
Sorry

asiancaucasian

Uh... what are you talking about? If you're talking about an eddy current dyno then yes, the Dyno Dynamics is and yes, it can be fiddled with but I also posted up a dynojet graph which cannot be messed with and it made MORE horsepower... go figure

SoloRacer

Sorry? How do you know it can't make that power? What "scientific" data or facts are you using? Just a "gut" feeling? Funny how racing bodies (JGTC, Nascar, etc.) rely on Dynojet numbers to ensure that cars are running legal. A blind test was done by Sport Compact Car where they took the same car to 3 different Dynojets on the same day. They all recorded power levels that were within a few HP of each other. Like any other measuring device consistency and repeatability prove the value of the unit. If we were to dyno a stock 951 Turbo S on the same day I know it would read much, much lower than Aarons car. For the record, with my 968 Turbo I ran 15 psi and made 418 rwhp on the same dyno. I'm not running the meth/water injection set up and my boost levels are lower but that isn't the point. The point is that the only reason you question Aarons numbers is you don't "believe" his set up can make that kind of power. We just proved that it does. Either that or you don't believe my KMR/Milledge built 968 Turbo with 16 valves, 3.0 displacement and 60-1 Turbo can't make over 400 HP.

SoloRacer

One other thing, Aaron can correct me if I am wrong, but the large dip in the A/F readings is due to the onset of his water/meth injection system. His system is a simple on/off style and that allows him to run a much more aggressive tune than a car running just pump gas.

alxdgr8

Your injectors must hate you. Have you logged duty cycle during runs?

Duke

It's easy enough to do some basic calculations that support the fact that these numbers are unlikely. But questioning dyno results usually don't lead anywhere and that's why I'm staying out of this post

I would love to see 1/4 mile trap speed and a 100-200 km/h sprint for that car. That would end all speculations. Trap speed should be around 120 mph and the 100-200 sprint should be a low 7 sec.

Rogue_Ant

What was the correction factor?

333pg333

Well said Duke. We still don't have enough cars doing the 100-200kmh type logs. Me included.
I would like to do mine but now with that exhaust, it's kind of noise pollution on the street.

Duke

Come on now Pat, just slip out after midnight and I'm sure you're able to find an empty road!

Duke

So here's the basic calculation I was talking about..
Let's calculate the crank hp from 448 rwhp by using 12% driveline losses = 448/0.88 = 509 crank hp.
Think of boost as a multiplier of the engine breathing capacity in N/A form. So next step is to compensate for boost. That is done by dividing crank hp with (atm pressure + boost level) = 509 / (1+1.45 bar) = 208 bhp.

This engine would produce 208 bhp in N/A form? Not likeley.
Remember that only modifications that improve the engine breathing capacity (VE) will let the engine produce more power without changing boost (simplified). That means that regular bolt-ons don't net you more power without upping the boost. However, if done right they will let you run higher boost without loosing efficiency.
And in this case about the only mod improving VE is the exhaust. Even with headers, head work, cam etc it would be hard to reach 200+ bhp in N/A form.

toddk911

So how did you go from 412whp on the first post to 442whp on your most recent run you posted?

Was that an altitude correction or did you adjust your tune/boost?

asiancaucasian

No correction, or I don't think there was. Only difference was that I was running 94 octane and it was a different dyno.

asiancaucasian

Haha no, but I'm worried about that as well. Must be very close to max.