DriveWay Labs Rear Diffuser - FT-86 SpeedFactory

[FRSfan111]

Lol already set money aside. Ill plasti dip black though

[mad_sb]

Originally Posted by Wonderbar

Well, I thought about taking it in an inch and a half off the end but it was unanimously voted against by the pre-release crowd. They also wanted the rivets. I understand it isn't for everyone and I may potentially build another version later but for now this is what we are running, I have other parts I am working to finish and push out.

Understood, I can always trim it down, just want a little more stealth. Any new on test data?

[Wonderbar]

Originally Posted by mad_sb

Understood, I can always trim it down, just want a little more stealth. Any new on test data?

Aero data is super expensive, wind tunnel time is like a house payment per hour. Ill wager my good name (haha) on the increased mpg at highway cruise, exact amount will vary due to driving style.

When I get to NC I will be looking at wind tunnel testing and try to afford it for you guys.

Honestly, once it is blacked out, it's super stealth, take a look at my version 1 prototype on my car in my build thread or the BRZ/FRS rear diffuser thread in chassis/suspension/brakes sub forum.

[adprokid]

Any plans for a single exit exhaust cover ?

[Wonderbar]

Originally Posted by adprokid

Any plans for a single exit exhaust cover ?

Keep calm and watch for future products.

[umpadupa]

Originally Posted by Wonderbar

Keep calm and watch for future products.

dont tell us to keep calm! my kidneys on ebay already!!!

[mad_sb]

Originally Posted by Wonderbar

Aero data is super expensive, wind tunnel time is like a house payment per hour. Ill wager my good name (haha) on the increased mpg at highway cruise, exact amount will vary due to driving style.

When I get to NC I will be looking at wind tunnel testing and try to afford it for you guys.

Honestly, once it is blacked out, it's super stealth, take a look at my version 1 prototype on my car in my build thread or the BRZ/FRS rear diffuser thread in chassis/suspension/brakes sub forum.

Autospeed has a lot of good articles on budget aero testing, you do not need a wind tunnel. Air pressure measurements, for example, can be taken from the void area (between the trunk pan and where the diffuser would be) before and after... a reduction in pressure with the diffuser should indicate a reduction in lift if i am not mistake. You would certainly want to confirm it is not catching additional air at high speed causing parachuting, this i think would show as an increase in air pressure.

You can also use linear potentiometers on the rear shocks (or any two points between the chasis and the control arm) to measure average ride height differences at speed.

Lastly, as you mentioned, the mpg figures (if measured accurately enough) should be able to show a reduction in drag if one is present.

[Wonderbar]

Originally Posted by mad_sb

Autospeed has a lot of good articles on budget aero testing, you do not need a wind tunnel. Air pressure measurements, for example, can be taken from the void area (between the trunk pan and where the diffuser would be) before and after... a reduction in pressure with the diffuser should indicate a reduction in lift if i am not mistake. You would certainly want to confirm it is not catching additional air at high speed causing parachuting, this i think would show as an increase in air pressure.

You can also use linear potentiometers on the rear shocks (or any two points between the chasis and the control arm) to measure average ride height differences at speed.

Lastly, as you mentioned, the mpg figures (if measured accurately enough) should be able to show a reduction in drag if one is present.

Agreed on all, I plan on a coast down test as soon as I get some time. Air pressure testing should be easy enough. It comes down to time.

[Gunman]

Coast down tests, and some oil drop tests, fyi engine assembly lube is a little thicker, and probably work better on the underside. By looking at the oil streaks, you can see if the air is staying attached, if you need more or fewer strakes, if strakes should be curved, etc. Yarn tufts work too, but you need to video tape them, where as oil streaks stay when you stop.

[jthornton1993]

marking

[FRSfan111]

I don't want to wait to order lol :/

[midnight23]

Is there plans to make a front splitter also?

[Wonderbar]

Originally Posted by midnight23

Is there plans to make a front splitter also?

Yes.

[Wonderbar]

The plan is to have a full matching aluminum aero kit.

- 3 Piece front splitter
- side skirts
- full underbody tray
- fender aero "flares"


I plan on some dress up parts as well.