andrew6321

Sorry if this has been done to death, but here goes....

I know Subaru officially states output for the MY98 at about 208hp, but looking at the dyno listings section, there seem to be a good many 'standard' '98 cars making in the region of 230+. Is it generally accepted that Subaru is understating the power output, or are these dyno outputs closer to the truth than Subaru's own figures?

Dark

iTrader: (1)

From memory of the dyno at Star Performance, my MY98 was the same as several MY99's, all with approx 220bhp and 210lb/ft. I think all had either Magnex, SS or similar backboxes.

The actual dyno figures can't be relied upon due to variations between equipment, weather conditions, etc but this showed that there was very little difference between MY98 & MY99.

Mark

Yex

Andrew,

Have a look at the DYNO link at the top of the page, the information contained here gives a good idea of what to expect with what modifications etc. From previous discussion on the BBS the Powerstation rollers are more accurate in terms of readings, if upsetting a few people

Regards

Yex

edited because I can't spell after a lunch in the pub

[This message has been edited by Yex (edited 14 December 2000).]

andrew6321

Yex - I posed the question after reading the dyno section! I guess I was really saying - do standard MY98s make more than 208hp in 'real life'...? and if the figure really is closer to 220/230, why does Subaru only rate it at 208?

Andrew

Yex

Well that's b0llocked my theory.....so I'm back off to the pub

Seriously though, I have no real technical expertise in this field


Yex

Gary Foster

The Subaru figure of 208Bhp will have been produced on an engine Dyno, and will therefore be 100% correct.

The other figures are done on a rolling road to give the torque at the wheels, the flywheel figure is then 'interpolated' (guessed) from this.

Unless Subaru lied (why would they ?), 208Bhp is the *real* figure.

Rolling roads are notoriously unreliable, take all the figures with a pinch of salt and allow for a certain % of error when comparing two different runs.

Gary

(Ps, I prefer to look at the torque figures and when thats produced, it's a more useful reading - unless you're planning to brag about it in the pub, in which case just make it up )

DJB

It has often been noted that the figures produced from Power Engineering dynos are higher than those from Powerstation (on the same car at similar temperatures). Which figures are correct is difficult to know. Calculated flywheel power output (which is the figure you see on the dyno site) is derived from power at the wheels and is only an estimation since transmission losses are very variable.

Overall I think that in most cases, the true power output is higher than the manufacturer's quoted figures but I don't think there's much in it.

D.

ps. posted 1 minute after Gary - hence similar comments.


[This message has been edited by DJB (edited 14 December 2000).]

sunilp

One reason why manufacturers, including Subaru, understate power, torque and other performance figures is to keep insurance premiums down!.....we dont know of anyone who has had their scooby lump on a bench dyno yet but i dont think that 208bhp is gospel.

Sunil

Gary Foster

Oi !

How did this get here !, wasn't this a serious post ?, I even posted a serious reply on her !!, spent ages getting all the words in the right order and everything

Reading it again, it almost sounds like I know what I'm on about

Gary Foster

Ooops sorry, thought this little baby had been relegated to the muppet forum what a muppet

must get out more

andrew6321

Gary - you gave me a shock old chap! To think such an innocuous question could be muppetised....life's unfair enough as it is...!

Gary Foster

Doh !

It was late, I was tired, had a couple to drink, thought I'd clicked on the muppet forum .. rest is history.

Obviously been spending too much time reading those muppets threads ..

Stef

Gary is right.
Subaru get their figures from a proper bench dyno, and should be considered accurate.
This figure is for a brand new engine of course, so there will be some increase as the engine loosens up.
I doubt very much it's got anything to do with underestimating and insurance, as 15bhp would make no difference at all to it's grouping.
A UK 98 car with decent breathing mods will produce somewhere in the region of 230 'real' bhp on an engine dyno methinks, not a standard one.

Stef.

sunilp

Do you really think so, i dont!

What is grouping based on then, amongst things?