M3 Dyno Time..

[DrphTa 5]

Im looking at putting my car on the Dyno in a few weeks. Only to get an idea of where im starting from before I get into changing/modifying the car.

Does anyone have an idea of what I can expect? I know you lose 25-30% power at the wheels, so I should be seeing 240hp atw?. Ambitiously speaking

Dyno charts on similar cars would be great

[Jeddy 0]

Have a look in here:

http://www.bimmersport.co.nz/forums/index.php?showtopic=8775

Atta and 'morerevsm3' specifically.

[Jamez 2147483647]

With the S50B32 in the racecar I got 250rwhp @ 7800 rpm, no engine mods, just an aftermarket ECU with a 3 inch straight pipe exhaust and no maf

edit - Also got 330 flywheel hp @ 7800 rpm on another dyno out west.

Edited February 6, 2011 by Jamez

[DrphTa 5]

Yea I saw his 94 m3, 200kw atw is very decent. I'd be happy with anything over 180kw.

[Michael. 2313]

Usually with automatics you loose 25-15% of the power, manuals seem to be around 1/2 that, maybe 10-15%

I would say you should get at least 180rwkw up to 200rwkw.

But then again factoring in the age, mileage and modifications to the vehicle will vary the output, also dyno readings do vary machine to machine, especially if you compare rolling road types to the fixed hub ones which give a more accurate result.

Hope you get the result you want Ethan!

[DrphTa 5]

Will definitely stick to the same Dyno. I think my AFM maybe stuffed so I want to get the checked out before I jump on it. More so just to see what im starting with before I um... go FI

[morerevsm3 7]

going FI? now your talking

dyno dynamics are typically 25-30% loss

3 litre M3 usually make 155-165rwkw, and 3.2 make 160-170rwkw stock

[nastnas 9]

the injector duty cycle is the energy into the system before there are any losses, ie chemical and mechanical losses....

IMO just going by the injector duty cycle is a crude way estimating power.... its just puts you in the ballpark range....

[nastnas 9]

if it was an accurate way of measuring we would not have dynos and engine test facilities...

im not here to start an arguement mate... this is where it ends for me.

cheers

Realy? wow after 27 years of doing this and afew world records i better change the way i do things

[morerevsm3 7]

I use many types of dynos with my customers in fact we used hi velocity's dyno last week with a turbo mk2 escort i did and his is a dyno dynamics and using a 15% loss the engine number based on injector duty cycle was bang on.

That was backed up with the turbo spec i built for it and based on the comp map that also confirmed it was bang on at 15% loss, so dont agree on that and if the correction factor or sae setting was correct it wouldnt be anywhere near those losses unless you d*ck with the numbers to make the customer feel better.

If you run injector cycle against its flow rate in hp thats one figure you cant d*ck with unless its running way over rich which then it wouldnt make good numbers, calculating hp is a very basic thing.

in Australia, we don't convert to BHP, only talk RWKW unless it is on engine dyno, and there are at least 50 examples of same motor being on engine dyno, then on dyno dynamics in shootout mode (no operater adjustable settings, as long as intake temp probe is actually in intake) in a car, and 25-30% is real. the only proper way is to have a known weight, and mph at drag strip, the long black dyno doesn't lie