Phil Harrison

You'd summarised it correctly John. I was asking why the WRC appeared to have a WRX scoop, when you (and others) had said that the "fuglier" STi scoop was so big 'cos it needed more air?? As a supplementary, I'd been puzzled by your reply, since the cross section of the grille-thingy (top of the intercooler??) below the scoop hadn't changed between 02 & 03, and nor had the nominal bhp/torque figures. If STi-wanna's answer "it's 'cos the old scoop can lose some necessary air volume at high speed" is right, then your original reply is amplified, and I'm content

Phil

[Edited by Phil Harrison - 7/3/2003 5:33:37 PM]

greasemonkey

It's there for cosmetic reasons, and, I believe, because the WR car rules include some sort of provision about side body silhouette matching the road base car (which is part of the reason why Ford made the point of the 03 Focus WRC being based on the American Focus ST).

If the scoop had any positive effect on the cooling, it wouldn't have been completely blanked off on the 97-02 WR cars!

I suspect the only reason it's open on the '03 car is because it's so damn big, the drag penalty, and dirty air caused by blanking it, would have been worse than letting it into the engine bay.

Not in a million years will the scoop allow air out at speed, unless it was turned backwards.

That's why the scoop used to be blanked

The air drawn through the rad and IC is taken straight out of the new age WR car by the air exit in front of the scoop. The P2000 had a similar arrangement ducted into the twin vents.

As has been said elsewhere, it uses the WRXIII one, not the larger STi part.



[Edited by greasemonkey - 7/3/2003 6:21:42 PM]

Phil Harrison

Looking at the Subaru Ad in Autocar, Solberg's car gives the impression of not having the Road-STi scoop - indeed, it looks to me like being the standard WRX scoop. What do the rally-experts say?? Is this consistent with the view that the STi8 scoop is so large because even more air is needed than STi7 collects?

Phil

DBY

Phil its a visability thing in the summer months it takes away all the Flies and Moths that would otherwise hit the windscreen!!

Regards

John

Paulo P

iTrader: (42)

The WRCs have front mounts dont they?

Paul

Phil Harrison

LOL @ DBY

Phil

dsmith

WRCS have front mount intercoolers for years - so scoop is purely cosmetic.

Deano

Brun

STi wanna Subaru

iTrader: (1)

I think you've missed what Phil is asking.

The STi 8 scoop can only help increase the intercooler efficiency which is a good thing.......I don't know what it does to the drag coefficient though. Which is why I suspect the WRC has the STi 7 scoop. I retains the Impreza look but with less drag.

Some people also have said that with the old scoops at high speeds the airflow actually missed the scoop and thus intake temps went soaring.....one theory on why several engines have let go after sustained high speed runs. Maybe the STi 8 scoop was looking to address this issue??

Phil Harrison

Thanks Guys.. dsmith answers part of the question precisely (tho' I'm surprised that any strictly unnecessary interruption in airflow over the bonnet would be tolerated on a competition car, unless it happens to create beneficial airflow instability)

STi-wanna is spot-on in his reading of what's bugging me.... There was a debate as to whether the new scoop was cosmetic or 'necessary'. I've always been unhappy with the view (expressed with some authority IIRR by John Felstead) that it provided 'more air' since all the gubbins below the scoop is apparently identical as between '02 & '03; and the engine output figures are, to all intents and purposes, identical. I find the extra insight in your answer very credible, STi-wanna, Thanks

Boyakasha

iTrader: (2)

If you have seen the WRC car in the flesh there is not even a hole in the bonnet where the scoop sits. The only hole is at the front where the carbon fibre duct for the Intercooler is.

It is amazing how much room there is in the WRC cars engine bay.

johnfelstead

not sure what you are saying phil?

The scoop on the WRC car is not the STi7 scoop, its the standard blobeye MY03 WRX scoop. The scoop does nothing on the WRC car, its there for cosmetic reasons so the car looks like its road car brother. The intercooler is in front on the WRC car.

rb5 286

iTrader: (2)

this picture doesnt quite show u but u can get a good idea....


pic courtesy of swrt.com

u can see where the i/c is mounted so the scoop doesnt feed it.

the scoop is mainly there to aid in airflow around the engine to keep it cooler and also to allow air out as you dont realize the air pressure forcing up from under the bonnet at high speeds although most of this is reduced by the undertrays.

But the wrc car does use the same scoop as the STi8

johnfelstead

the WRC car does not use the same scoop as an STi8, it uses the WRX MY03 scoop which isnt as tall.

Also, air doesnt exit the scoop, that is imposible as the airflow is inwards and down, not up and out.

greasemonkey

The reasoning is that if all the other bits under the bonnet are the same, the bigger scoop will increase the efficiency of the I/C by providing it with more cold air. Thus, while the headline output figures may stay the same, the charge temperature should be lower, theoretically giving better performance, especially in warm weather conditions.

The fact that the bigger scoop helps give the car a more aggressive appearance is, of course, a happy co-incidence.

Edited to clarify that the above applies to the road car only. The scoop on the WR car is utterly superfluous - there's plenty enough airflow available through the front.

[Edited by greasemonkey - 7/3/2003 7:55:15 PM]

Chris L

Seem to remember reading somewhere that they positioned the oil cooler near the bonnet scoop of the WRC car?? Might be complete rubbish, but it would make sense to use it for something.

Chris

johnfelstead

nope, they use a water to oil cooler too chris. Nobody serious uses an air to oil cooler these days on engine oil cooling.

The very early WRC Impreza used that to feed an airbox (it had the two perescope rad/intercooler air exits where the 22B bonnet vents are, but they havnt done that for a good few years now.

johnfelstead

under the bonnet of the current WRC car. more pictures on my website.

Chris L

I'll bow to your greater knowledge of these things John

Chris