2000 Toyota Celica (7th Gen) - Stock Spoiler

[aerohead]

Originally Posted by riddleyo

Well since I don't have Hucho's diamond yet, what do you guys think of this? It would be a small Kammback made from fiberglass attempting to follow the template line. It retains the rear visibility.

This is a shot in the dark, but... would the air detach from the kammback and hit the spoiler to increase or decrease drag?

I did the small Kammback on my CRX,but went ahead and extended the C-pillars along the 'Template' contour to fully capture a locked-vortex within the footprint of the K-form roof.
The fenestration below the mid wing was glazed with plex (like the next-gen CRX) an allowed no airflow.
As to whether or not the extension will reduce drag.By definition,it will,although maybe not enough to show at the pump.
The K extension is moving the separation point rearward into slower,higher static pressure air.Since the base pressure of the entire wake is governed by the pressure at the separation point it must be of higher pressure i.e. lower drag than before.
Do the tuft test when you can.And attach longer streamer tufts (say,3-ft/1-meter in length) at the top outer edges of the roof.If you have vorticity it will show up in 'outer space' flying up,outward,and away from the body,which might not otherwise reveal itself with the shorter tufts.A 'Chinese Dragon' will signify the vorticity.

[Daox]

I'm curious if you ever did the tuft testing on this car?

[riddleyo]

I'm still planning on it!

I've had to tear apart the engine and replace the timing chain, oil seals, alternator, and water pump. Then I replaced and repainted the fenders and bumper. Then I built a underbody aero tray out of choroplast. Then I got a scan gauge 2. Whew!

Now, I am coming up with a way to mount my digital camera pointing toward the rear of the car for the upcoming tuft test. Pics/video are coming!

[aerohead]

Originally Posted by riddleyo

Yup, there is a gaping large "hole" underneath. Would it simplify things if this hole was "filled", say with clear tape or some other clear plastic? It would turn it into a huge duckbill type spoiler.

When Pontiac chose this style of spoiler for their Trans AM Firebird they knew it didn't work as well for drag reduction as a simple 'flip-up' spoiler as on the Camaro.
But you do get better visibility when backing and they'll clear off snow better.
Without a wind tunnel it's going to be tough to outguess Toyota.
I'd be tempted to leave it alone.
PS If you have 'instant' data acquisition electronics,some cardboard and duct tape would tell you about blocking it.

[aardvarcus]

Just be glad you don’t have the “Action Package” rear spoiler like I do. Looks cool (subjective), but it is a lot higher up and larger. I believe removal is the only option for that spoiler.

I am interested to see your results. I have a 2002 GTS Manual Celica, and I have been slowly working on getting it aero-modded. I have done grill blocking so far, and have changed the tires to Michelin Energy Savers. I went 1.5" larger diameter from 24" to 26.5" to get the rpms down on the highway. Going to pick up the rest of my belly pan materials today.

[kach22i]

I'm guessing that because the roof plane is less than 22 degrees that air flow stays attached.

I'll go further in suggesting that the wing adds a small amount of down-force at the expense of a little bit of drag.

Overall a very nice clean car, add a chin spoiler and then drive like a little old lady and save a lot of gas.

[aardvarcus]

One question I have related to the flow attachment of the celicas is the rear third brake light. It is located at the back of the roofline just before the window starts on the rear hatch. It may not be obvious from the pictures, but this light protrudes up from the car by about 1/2" to 3/4". Does this bump serve some purpose, or would it be better replaced with a flush cover?