Removing Spoiler = Removing Downforce?
 

Hi,

I'm thinking about removing the spoiler on my Blob STI. Before I plan any further ahead, is getting rid of the spoiler going to negatively effect the handling?

Anyone got any experience of how the car handles without one?



Thanks,

I hate the 'pram handle' spoilers on Newage STI's.

I replaced them with the WRX style on my current widetrack and the previous STI.

The Spec D STI and several JDM models manage without the huge spoiler so I cannot see that it has any major advantage in terms of handling ?

Can't imagine it makes any difference on the road, so lobbing it off would save some weight and remove the 'look at me' element at the same time.

Thanks for the replies. Yeah this is what I was thinking. I think I read somewhere that over 120 or 130mph it does make a difference but since I'm not going to be tracking the car anytime soon I can't really see myself reaching those speeds.

Basically I don't want to get the holes in the bootlid filled in and smoothed over only to have to fit the wing again to stabilise the car.

A lot of people on stateside forums who run the wingless look or spoiler less look to us lot lol reckon the rear end gets a bit light and twitchy if you run without a boot spoiler but have the roof spoiler fitted

If I had a blobeye I would remove the spoiler. Looks good imo

Rear end is def lighter & follows suit as the front drives into the corner / mine is very tight tho been full polly bushed & under braced .. I bought a second boot & did the work to that , then it was just a case lifting the old off & putting new on ( adding lock mechanism only as de badged ) & changing the spring .. only time the OEM will return out of storage is if it ever gets sold lol
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I once asked a main dealer about the necessity for the high wing on my blob and if removing it would have a detrimental effect on handling. He said that he didn't have a definitive answer, but Subaru must have thought it would reduce stability enough for them to fit a diffuser to the Spec D where the spoiler is removed.
I have to say I think he had a point as removing the spoiler to make the car more discreet is one thing, but then adding something as minimal as a diffuser to an OEM car would seem a bit contrary unless it had some beneficial effect.
I guess you have to make your own mind up.

Wasnt it to aid in the "rallying" aspect of the car for the WRC that they kept for the road going version.

Ie extra stability driving somewhat sideways in rallying conditions, so on the road next to no effect for us to remove

Jazzy, what power are you running and what's your spec?

2.6 EJ257 closed deck , Darton sleeved , Manley competition pistons & rods / sitting on a standard location MD321V billet ... it needs to go rotated as it handles the MD with little effort .. ecutek software , race rom but no launch control , I'm an old boy lol

:thumb:

appreciate all the replies!

That looks awesome!
I'm guessing removing the wing doesn't totally ruin the handling, sounds like your car must be pushing out a fair amount of power with those specs.
Not a bad shout about keeping the original boot lid as a spare too!

Thanks,

Thanks for the kind comment Rich

I own a Spec D Hawkeye. I've driven it round the TT course, with some very fast sweeping corners and with all the combinations of spoilers. In order of twichiness/looseness of the back end it's in this order:

Full rear Wing AND roof vane definitely the best feeling.
Full Rear wing, no vane. OK but you can tell the difference!
Low spoiler (WRX/Spec D) AND vane- worse but acceptable.
No Spoiler or vane. Just unpleasant at 120-140 on bends.
Only the top Vane- No thanks, my sphincter was definitely too tight around Brandish that time. No confidence at all!

So, empirically tested. If you want the Roof Vane, put something on the boot!

Basically, your car behaves like a cambered aerofoil. The more you fit a lower front lip or deep front bumper, or indeed lower the front, the more camber you have and the more lift you generate.

To kill that lift, you fit the rear aerofoil. This gives downforce with low drag. The lower part is a Gurney flap and does cause a lot of drag. It also causes roll over that stops the air from under or around the sides from filling in the gap and causing bad crosswind stability.

The Vane causes air that would break off at the top to come down. it reduces flow across the rear screen from the sides, again helping in crosswinds. Where it affects the car the most is in presenting the air to the rear aerofoil, the upper element of the big wing. It effectively increases it's angle of attack to the airflow giving a lot more downforce with minimal drag.

Yes it really works. The vane alone, causes a more efficient camber lift and will allow the car to lift more than without it. Hence on it's own it's the worst setup to have for stability.

Hope that helps.

holy thread revival!..
appreciate the reply, very helpful.

I actually went ahead and removed the spoiler, and I can feel a difference. It depends on the conditions but at around 80+ it doesn't feel quite so stable as it used to with the wing.

Any pics without ?

I actually dont have any good pictures where you can really see the back to be honest.

And what i've done to the car might divide opinion...
Its a bit lower now but you get the idea

https://cimg5.ibsrv.net/gimg/www.sco...4b9bbb5e7c.jpg

Thats really nice pal. the wide arches do make it.