engine undertray on my04 STi
I'm interested in ths too - I have a JDM WRX with an undertray and I was thinking of ditching it when I do the oil change - my engine bay doesn't seem to have been kept all that clean.
Took mine off 18 months ago (JDM '05 STi). Engine does not get any dirtier - although I clean it yearly anyway, and oil temp dropped by nearly 10C as well.
Some will say that it's needed to assist airflow through the engine bay but I've not had any problems.
Some will say that it's needed to assist airflow through the engine bay but I've not had any problems.
Not entirely sure, as aerodynamics seems like complicated business, but I'm thinking not having one might affect things such as:
* fuel consumption (increased drag)
* high speed front end lift - worse handling, breaking etc.
* fuel consumption (increased drag)
* high speed front end lift - worse handling, breaking etc.
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From: 2010 Time Attack Club Pro Champion - Powered by ScoobyClinic
I wouldn't remove it for the above reasons, a flat underside at the front will be better for airflow under the car than all the lumps and bumps you'll expose if you take it off, the flatter the underneath the better 
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Well ive just taken mine off. the two main reasons not to (stated above), mean nothing to me, firstly aerodynamics :- my scoob poodles round at 30 mph so im not worryed about that, and fuel consumption :- doing a few hundred miles a year, i aint worryed. lol.
now its a little easier to do oil changes and it mite help with under bonnet temps too. we shall see.
dan
now its a little easier to do oil changes and it mite help with under bonnet temps too. we shall see.
dan
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From: 2010 Time Attack Club Pro Champion - Powered by ScoobyClinic
4 bolts & 2 clips from memory, having just replaced the one that was missing off my friend's Type R 
Made a huge difference to my lap times at ScoobySprint at the weekend 
Made a huge difference to my lap times at ScoobySprint at the weekend
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From: 2010 Time Attack Club Pro Champion - Powered by ScoobyClinic
No idea!! Maybe if we got out of 2nd gear it might have!
I've read something, somewhere, on how Subaru reduced lift by adding underbody flat panels on the newage cars, not just the front tray but panels on the gearbox, down both sides of the prop and the diffuser at the rear. You'd need to be doing motorway speeds to notice any difference though.
Maybe if we got out of 2nd gear it might have!I've read something, somewhere, on how Subaru reduced lift by adding underbody flat panels on the newage cars, not just the front tray but panels on the gearbox, down both sides of the prop and the diffuser at the rear. You'd need to be doing motorway speeds to notice any difference though.
Great job there Mate
