crawf8

Hello,

Had my car on the rolling road at AVA today, it was an FTO owners day, but there was a few proper cars there as well , including an EVO 6 TME with 262 BHP at the wheels , and a Pulsar GTI-r with 258BHP at the wheels.

My car (Catalunya) produced 188.8BHP@6000rpm at the wheels, it was running 1 bar. Apparently that is a bit above standard but I wouldn't know! I just drive it .

It was a great day, a bit cold though! Thanks to the FTO guys for letting me join in the fun. The guys at AVA seem to know there stuff, and were very helpful. I've never been to an RR day before but they seem to have a good set up.



Anyone know how to convert power at the wheels to power at the fly wheel?

Cheers,
Crawford.

Robertio

iTrader: (1)

If your car is standard, or close to, then their rolling road is a bit on the optimistic side. Drivetrain losses on scoobs are huge, at Star my @wheel figure was 133, and flywheel was 218.5bhp

There is a dyno page around this site somewhere, if you have a look at that you will get the general idea.

crawf8

My car isn't exactly standard it has a magnex de-cat centre section, stainless backbox and an ITG panel filter.

They don't have a measurement of power at flywheel at AVA, but they gave me an estimated guess of ~220bhp at the flywheel. I don't know much about cars but that seems about right to me.

My friend has had his car on the rolling road at Star performance and now AVA and he got practically the same power at the wheels on both. Although having just looked at the dyno pages 188bhp does seem a bit high! although losing 30bhp through the drivetrain, seems more realistic than 90bhp. I'm confused!

Anyone else had their car on at AVA to compare results?

Cheers,
Crawford.

Edited to say my friends car is a modified pug 306, i.e. front wheel drive not AWD, maybe their's something in that?

teknopete

Crawford,

Sorry to say, that a 30bhp transmission loss is actually more consistent with a 2wd vehicle as you already susspected
Through all the RR days we`ve held at Star the general transmission loss appears to be between 70 to 90 bhp. There was a lot of research and testing went into the setting up of Star`s dyno to get the correct parameters for running Subaru`s and Evo`s. As initially the load was switching in at the wrong time. These flaws as far as we are aware are now all ironed out as the results achieved on recent dyno days have been consistant.

Yes, 188 at the wheels does sound a little on the high side
when compared to some of our old results.
see http://www.scoobymods.co.uk/SRollingRoad01.htm

Maybe we need 2 spend a bit of time getting AVA`s road setup to the cars as well.

Pete

iainalpine

hi guys. i have used AVA for sometime now. infact it was my first port of call when i got the scoob 2 months ago. i got around 138 at wheels b4 my car started to det just after 5000rpm. you are right, the figure you got is a bit high for a standard car. i no alan and rest of the guys down there are keen to get more scoobs on the rollers. infact 1 of the boys down there is on the look out for an impreza so there is an interest to see what they can do. when i was on the rollers at star my power at wheels was a litle higher i think. all that had changed was the tech 3 by john. looking forward to having a few rolling road days at ava as i stay about 1 mile from them.
cheers
iain

crawf8

Thank guys, so I'm still none the wiser as to what the bhp of my car actually is . Probably not that impressive anyway.

Oh well, maybe I'll go to the next RR day at star.

Cheers,
Crawford.

stage 1

You will get higher figures at the wheels on ava's rollers due to the fact that they run cars in 3rd gear and the fact that the rollers are much much larger than most others. This means that there are much less losses than comparable to star etc. This is due to windage losses with spining the retarder and the lower speed involed etc.

What they have aimed for is very repeatable consistant runs. This helps them diagnose problems and guage tuning results. Think they are also recording boost v rpm, inlet temps, turbo outlet temps etc etc now as well as room temp at rpm so you can see that the air in the room is recharging properly etc.

I have helped lift the actual weights used for calibrating the rollers so doubt there is anything dubious about the measurement but that the losses are not understood. They also measure "BRAKE" horsepower at static RPM for accuracy .

Martin

crawf8

thanks Stage 1 ,

but I'm confused , my car got 188.8bhp at AVA but if I had taken it too Star it would have been more like 138bhp, so what should I believe?
I was under the impression that the power at the wheels measurement was the one that could be measured accurately and the power at the flywheel was an estimate?

Ultimately the flywheel power they quoted me was about 220-225bhp which seems quite realistic, so maybe I should just stick with that instead of worrying what it is at the wheels. It is quite an impressive set up they have at AVA, and that fan! it was colder inside the building than it was outside!

[Edited by crawf8 - 10/28/2002 11:29:06 PM]

Lambchop

i use ava religously and would go nowhere else

i have a *cough* saff cossie that makes 235@wheels

nice to know i could toast a scoob nae bother lol

whats a scoob weigh?

chop