#FinallyGotSomeAeroFTW!!

It works. A properly sized and AoA'd spoiler most definitely makes the car faster around nationals speed autocross courses... how much faster, that depends on alot of things. You certainly won't go any slower. Just from my own experience, our local SP hotshoes Billy and Bob Davis have tested their aero package (front splitter and rear spoiler) on their CSP Miata consistently at a minimum .5+ second faster per minute on a national speed/style type of course. Some courses much more than that. Their testing included completely removing the aero and then putting it back on. These guys do alot of logging. Again YMMV, that's a megalight NB miata, you outweight them by well over 1000lbs, but even it's worth an averge of a tenth per minute on Bumblestook I think it's still well worth it. I would like to have a chat with Campbell, Schipkov, Vitamvas etc in the SP Beemers to see what testing they've done, I think that would be a good reference.

It's a totally different beast, but the amount of downforce that some of the Formula SAE cars are making (based on strain gauge testing) will blow your mind. Like, I don't even want to post the numbers I know of because they are so spectacular that I am quite confident some guys here would call BS. I wouldn't have believed it myself if I wasn't talking to a fellow engineer specializing in aerodynamics, with access to scaled wind tunnels and high end CFD software and other modeling tools. The point is, even at autocross speeds, aero means something.

Another data point I have seen personally was SSM hotshoe Jake Namer. He was chatting about his massive rear wing on the RX7. He actually didn't believe it was doing much. So, he took the wing off for a run. He was loose everywhere, and at the end of that run, he had the most epic high speed spin through the finish. "I guess it really does work" he said.

 

The big blade really on has a impact towards stability in high speed transitions on the Z. It makes the car easier to manage at the end of a slalom for example. The car is heading up this week for the front aero to be done.

 

Very cool. If you do some back-to-back testing, let me know, I am curious to see the results and get your feedback. The balance at 40+ may change so significantly that you'll have to begin tuning the aero balance. PJ Coralles and I (SM 240SX hot shoe) were talking more and he brought up the point that the Davis car saw a huge downforce gain up front by going to their large front splitter but less of a gain with the rear spoiler, to the point where it was causing some high speed oversteer! So they cut holes in the front air-dam to try and balance it. They tune the front aero grip by covering and opening holes. Being a roadster, you can assume the relative lower impact of the rear spoiler is due to airflow over the open-top being turbulent, and therefore not getting to the rear spoiler effectively. RobRob can probably give more educated feedback on this situation, but I suspect he would concur.

 

Unfortunately I won't have time to test the aero. My first event with it will be at the Devens Match tour then Toledo (where I really hope it'll make a difference).

 

ugh. i was hoping to avoid that this year.... but now it sounds like i may have no choice if everyone is on the band wagon....

 

can someone get me a weight on an ap2 trunk lid and or ap1 trunk lid?
Cr trunk plus wing 32 pounds
my pig is going back on weight watchers

 

I was holding off for the same reason but it doesn't help that it's quite noticeable when I'm the only guy in the S2 grid that doesn't have a spoiler. It just makes you wonder...would I be faster with one? I have a spare trunk lid and it's not that expensive to have made (or make yourself with some decent skills I guess) so why not. If it sucks, I just put back my other lid.

 

None for me this year. I just wanted to go with a big wing when I make the jump to SSM. What class do we have to move to allow for rear diffusers? They seem readily available for our cars...

-Marc

 

I tested the airbrake rear spoiler back-to-back on my FP car 2 years ago at the Blytheville Tri-State Tour event. We got fun runs, so we did 2 runs with and 2 runs without the spoiler for both me and my co-driver. Both of us felt like it made zero difference, and data pretty much backed that up. It came off the car for good after that event. I am toying with the idea of building a new one that is as wide as the fender flares to see if it helps at all, but I suspect it wouldn't be worth the time.

 

Today I ordered a part that went unnoticed ... the plastic piece that stops the accelerator from hitting the carpet/floor. I noticed that the accelerator felt like it had a stopping point, then would go a couple inches further. I wonder if that piece worked in sync with the DBW sensor at the top of the peddle and possibly a cause to my issues..

-Marc