Wierd Dyno result

[Knudsen]

Has anyone else had their 86 on the Dyno? Ive just returned from a trip to a dyno-guy, and the result was a little depressing.. On the road, the car is very fast, atleast it feals that way

Im not sure about the ingition is adjusted correct. I installed a milled head (-1 mm) and i could defently feal the difference then.

There will come a movie of the dyno-visit later

[The Doctor]

is this the RWHP or the HP @ crank?

Most of the time it's Crank HP, but sometimes they give the Rear Wheel figures, and then it isn't bad at all!

[Knudsen]

Well, i asked him and he said that it was crank hp. But that means that the car has approx. 95-100 hp@ the wheels. And that sounds funky... I hope he misunderstood me, and gave me the hp@wheels...

[The Doctor]

it could be that the 'correctionfactor' is wrong.

The dyno measures the RWHP and throws some mikey mouse correction factor on it and there it is: crank power!


That's a thing i don't understand. They know the RWHP exactly, but they use some fuzzy factor to get the crank HP. The crank doesn't roll on the road! And they measure the exact power at the wheels

In a RWD car, the loss is about 15-20%, so it could be ~127 Crank HP or ~131 Crank HP (taking 114 RWHP as basis)

[Ivan141]

No way would you get 113 hp at the wheels from a stock engine..
I fear that a lot of old 4age's dont make the 120+ hp that they should.
But then again a RWD car has more drivetrain losses compared to FWD so if the dyno guys used the regular loss percentage you would see less estimated HP at the crank. Some dyno's have a way to measure drivetrain losses exactly though..

I'm very dissapointed in my own 4age at the moment, I doubt it puts out even 100hp.. My exhaust leaks somewhere at the manifold and it just revs way to slowly, so I would consider myself happy if I had an engine that runs smoothly even though it dyno's at 113hp. My last engine revved like a champ compared to my current one, this one is less thirsty for oil though..

[jamiemirror]

Knudsen, what is ambient temperature ?

[Knudsen]

jamiemirror Wrote:Knudsen, what is ambient temperature ?

Ambient temperature? I dont quite follow you...

Ivan> I wouldt quite call my engine old, it has only 145K km on it. One of my friends got his Hachi dynoed to 120 hp standart...

[Ivan141]

Knudsen, was that on the same dyno?
Ambient temperature is the temperature of the room the car was dyno'd in, which is important for intake temperature and cooling efficiency..

[Knudsen]

Ahh, no it wasnt on the same dyno. I know that not all dynos shows the same result so i guess that i cant compare the results.. I would guess that the temperature is around 8-10 degrees. Its a cold day here in DK...

My 2 friends that was with me today, was also surprised on the result... One of them has a Nissan Almera Gti that also got tested today (159 hp) and i do the sticky to him from 0 to 100

[KristianAE86]

Knudsen Wrote:Well, i asked him and he said that it was crank hp. But that means that the car has approx. 95-100 hp@ the wheels. And that sounds funky... I hope he misunderstood me, and gave me the hp@wheels...

we tried my car last year with the new G-tech pro Comp.

It is an Accelerometer.

We got about the same figures. as you did Knudsen.


Kris