Just had car dyno'd. Waay too much power

[BLSTIC]

Yeah, 97.6 kw at the wheels for a standard 1995 Legacy 250t.

I mean it has 120kw out of the box, it's 15 years and 220,000km old, and it's an automatic AWD. Surely I can't possibly have 97kw at the wheels after all that.

Has anyone else had an unfeasily high power reading before?

(oh, my EF falcon, with 6rwkw and 100kg on the legacy, was significantly faster)

[Guest boostcut]

120 kw would be a factory at the engine figure, and your 90 odd kw is probably about right either that or the dyno has a correction method applied to change to engine power not at the wheels

[BLSTIC]

I think it can't have that much power because it doesn't feel anything like ~100kw at the wheels should in a 1450kg car. Also my EF Falcon (with 157kw @ flywheel new, and 290,000km on it) was measured at 103rwkw (different dyno) and it was significantly faster in anything other than a standing start, despit weighing in 100-150kg heavier.

I'm aware that the 120kw figure was at the flywheel, that's why having ~100kw at the wheels is so confusing, especially when the car is so slow. They weren't saying that it was a calculated flywheel figure or anything like that, so it's kind of hard to believe. Maybe this is one of those dyno's where a standard BF5 GT can roll out 150kw at the treads (more than they made at the flywheel when they were new)...

[BLSTIC]

I can ignore torque completely because of gearing. Power at the wheels and mass of the car are the only things that are really important (aside from traction, which neither car has issues with off the line). At 55km/h the subaru is doiong roughly 6000rpm, and allegedy making 97kw. At the same speed the falcon is doing about 3500, and making 80kw or so.

If both cars actually are making as much power as they are supposed be, the subaru shoud be significantly faster (until it has to change gears), but it isn't, they feel about the same.

So I'm left with two possibilities: The subaru makes less power than claimed, or the falcon makes more. If the falcon didn't make the same amount of power as every other stock EF-AU that I have heard of, it would be an option. But 100-110rwkw seems to be the norm for them.

[Guest keltik]

Were you running it on force 10 or maybe some octane booster? Did you have the "POWER" button pressed? That stuff will add 30kw no worries

Experience has taught me dyno peak power ratings dont mean crap. Just look at the results RAB-B got on his dyno day, 85kwatw and i could only just stay on his bumper up to <very high speed>

[Joker]

yea thats average for autos on Dyno - even TT' ones

[Max Headroom]

 BLSTIC said:

I can ignore torque completely because of gearing. Power at the wheels and mass of the car are the only things that are really important (aside from traction, which neither car has issues with off the line). At 55km/h the subaru is doiong roughly 6000rpm, and allegedy making 97kw. At the same speed the falcon is doing about 3500, and making 80kw or so.

If both cars actually are making as much power as they are supposed be, the subaru shoud be significantly faster (until it has to change gears), but it isn't, they feel about the same.

So I'm left with two possibilities: The subaru makes less power than claimed, or the falcon makes more. If the falcon didn't make the same amount of power as every other stock EF-AU that I have heard of, it would be an option. But 100-110rwkw seems to be the norm for them.

You can't ignore torque at all, because that's the only thing that a dyno measures. You've already identified a major difference for yourself when you state that the 250T was achieving peak power at 6000rpm. Both cars have completely different torque curves and different gearing. How those two characteristics play out in the real world are significant.

To confirm that, try changing the final drive ratio in your Falcon by fitting different tyres. Just by fitting high profile tyres you can change the feel or responsiveness of a car without changing the cars' weight or engine output. The combination of gearbox ratios, final drive ratios and the rolling diameter of the drive wheels have a huge influence in determining whether a car will feel "peppy" or flat.

For a bigger contrast, take a drive in a diesel truck with 100kw at the rear wheels . . . .

[Guest boostin]

Who cares what the dyno says. Go by the seat-ometer. Dyno results are only good for checking AFR's and wank factor....