cyotani

iTrader: (8)

On the spoiler discussion: It seems like they can make good down force at low speeds but have excessive drag at higher speeds (good for autoX). So how would a DRS (actuate the spoiler flat to reduce drag at high speed straights) on a rear spoiler similar to the BlackBird one compare to a APR 2D wing on a track. Could this be a best of bet world solution assuming the control system is well tuned and the actuation is sufficiently quick. This is a project I've been considering tackling in the future.

OGRacing

iTrader: (1)

you need a wing slider -

JOES Racing Products 25983

ThePass

iTrader: (3)

I ran a spoiler at ~35* (fairly steep) at many full-size tracks and up to about 130mph. I saw more downforce from a COT wing (which is a relatively low-downforce, low-drag design). YMMV?

A much better avenue to explore IMO is a wing that will produce all the downforce desired which actuates to a shallow angle on the straights. Keith Tanner has been playing with this type of system:
https://www.miataturbo.net/race-prep...ng-test-74913/

cyotani

iTrader: (8)

They do not give any specs on actuation speed with that. I'm not sure if it would make a suitable DRS actuator. It might just allow for slow adjustments then lock in the setting rather than repetitive quick actuations.


But hardware aside... I'm considered more about the actual theory of a DRS spoiler miata than the hardware side of things at the moment

OGRacing

iTrader: (1)

i'm never listening to roman again... that's for sure. :/

Leafy

iTrader: (1)

Its because you didnt go bowling with him.

cyotani

iTrader: (8)

So if the spoiler had more Down force at those high speeds it most likely has more drag. If your not traction limited on the straight why not use DRS on a spoiler to reduce your Down force and therefore reduce your drag as well to help use more of your power for acceleration rather than overcoming the drag force.

what you just described is drag reduction system. More downforce when you need it, less drag when you don't

ThePass

iTrader: (3)

Woops one inacuracy in my previous post:

What I meant to say was that Keith's been experimenting with actuators on wings, but not quite the same function as I suggested. His is a version that operates as an air brake, whereas I'd like to see a wing that decreases angle by a method of driver-controlled input on the straights to r educe drag.

cyotani

iTrader: (8)

That makes more sense. Now we're on the same page.

Ya I was wondering why keith went with an air brake system. Maybe it was easier control system to implement based off brake pressure or something.

ThePass

iTrader: (3)

You may be misreading my post. I'm saying even at 35*, the spoiler did not seem to provide the same downforce that a wing did. This is not back-to-back same day tests, but same tracks over a span of time as I increasingly added aero to the car. I do not feel any confidence that a spoiler at any angle could balance with the front aero I have now (and there is still much more room for increasing front downforce).

Also, there are triple-digit turns aplenty at the racetrack. I wouldn't be too excited about a spoiler system that decreases angle according to speed, and leaves me with an unbalanced car in the high speed sweepers.

-Ryan

cyotani

iTrader: (8)

ya, sorry i did misread that. From what I understand, spoilers work well at lower speeds and have very high drag at larger speeds. A wing is a better aero solution overall, but especially better at high speeds with it's downforce to drag trade offs. But you pay for that benefit with it's cost and difficulty in mounting properly.

Yup, I considered that issue. For mid corner stability I was planning on having steering angle as one of the control inputs. ie: do not actuate flat when steering angle is greater than X degrees.

cyotani

iTrader: (8)

Back to the OP's question:

It sounds like a 2D wing works best if you can get it high enough above the vehicle to see an un-disruption air stream (ie: at level or above the hard top)

The reason for the 3D wing's shape is to attempt to optimize the airfoil shape for the varying streamline directions closer to the trunk lid, caused by air flowing over the car's body. see the video bellow for a good explanation.

OGRacing

iTrader: (1)

i see no video :(

cyotani

iTrader: (8)

idk works for me.

"http://www.youtube.com/watch?v=SeKKzFSNRFo]APR 2D wing SuperMiata Crusher - YouTube"

OGRacing

iTrader: (1)

looks like 3D for me. did everyone see that there is a new gt250 wing out. seemed to have substantially more downforce and allot less drag.

cyotani

iTrader: (8)

Here is a good tech article fro APR of the 3D wing. They use a 15 degree greater Angle of attack increase at the outer edge compared to the inner. It's really hard to say which is better without air tunnel testing for your specific vehicle. Personally, I would go with the 2D wing mounted higher up.

http://www.aprperformance.com/index....sk=view&id=181


A good visual of the air streamlines:

greddygalant

iTrader: (3)

So concensus is gtc300 ?

MX5JER

Opinions on this one?

Fiberglass CCP Fab Race Car Wing | eBay

Jeffbucc

That is the choice I made based on my cars latent potential and me trying to utilize it in the future when I get my potential up to the car.

natedawg

Would like more info as well.