NOT Another...Yes...another auotx build thread

[csamsh]

Don't take this the wrong way, but that is weak. I know that sounds like I am being offensive, I'm really not. Yes I know that you don't waste your time on stuff that isn't effective. Consider this as my point....someone could just put a picture of a Griggs torque arm on a car and do the same thing. Know what I mean Vern?

How much did you raise your rear spring rate to accommodate?

Don't be mad at me.

I haven't tested it yet. However.....You'll find this spoiler design on probably....the entire field of fast street prepared cars in the SCCA autox nationals paddock, so I'd say either it works, or there are lots of fast people who are stupid.

I'm not raising the rear rate.

 

[modernbeat]

..How much downforce to you estimate that it generates at speeds comparable to other alternatives ?

Don't be mad at me.

I didn't estimate. We built it to the maximum size allowed and with some adjustment, tested it for best results (not knowing what sort of downforce we got, but that we got the best time on the test course) and then left it alone. We quickly abandoned it, along with ESP to do time trials and used a much more efficient wing. For the few times we went back to autocross, we ran in Street Mod or CAM which allowed the wings at that time.

 

[I am Legend]

I didn't estimate.

 

[modernbeat]

Actually, I use a Remington 700

 

[csamsh]

Actually, I use a Remington 700

With one hand, and sunglasses? Badass!

 

[frank s]

With one hand, and sunglasses? Badass!

Is this really tech?

 

[csamsh]

Is this really tech?

yes

 

[sheizasosay]

I didn't estimate. .

That is past tense.

 

[zquez]

Have you done any events with the new spring rate?

 

[csamsh]

So...I picked up on maybe a point of confusion you have- a spoiler like this is the only rear aero that is legal for the autocross class I'm building the car for. A wing is probably better, but I can't use one. So, this is an example of a rules set picking your parts for you.

 

[csamsh]

Have you done any events with the new spring rate?

No. Still waiting on parts from AST

 

[white86hatch]

No. Still waiting on parts from AST

Because they apparently send parts to the USA by carrier pigeon....

 

[Boaisy]

One of the quickest SCCA AutoX'ers in the Mid-South is Richard Holden with the "Red Rocket" Nissan 240Z. Ever since he put this aero setup on, the car has pretty much driven on rails (aside from the stiff ass suspension), and is almost always FTD for the local SCCA Chapter AutoX's:

and then almost every CRX/Civic Hatch that comes out has the same setup:

We have a guy who drives a C5 Corvette with a wing rather than a spoiler, but it is because his co driver set it up more for road racing than AutoX (sorry only pic I could find of the car):

An then finally one of the guys from NASA took a few Go-Pro mounts, and made a DIY spoiler setup for his C4:

He said he could notice a difference, especially when we run high speed autocrosses at MIR, with the spoiler on there. Since it is just Go-Pro mounts, he is also able to let other people use them as well. This setup also did not penalize him on anything with classing for the way it was setup.

I'd say the back spoiler has to do something.

 

[claudermilk]

Consider this as my point....someone could just put a picture of a Griggs torque arm on a car and do the same thing. Know what I mean Vern?

Didn't someone effectively do just that? Then you guys all spent the next couple of months ripping him mercilessly for it (not that it was totally undeserved).

I cannot imagine these huge spoilers being ineffective. I don't think everyone in the classes that allow them would be running them if they didn't. Logic tells me they are so damn huge so they work at the lower speeds of an autocross. I will be interested to hear how it works once the autocross season starts over there.

 

[modernbeat]

Didn't someone effectively do just that? Then you guys all spent the next couple of months ripping him mercilessly for it (not that it was totally undeserved)...

Well, we did test it. But we didn't measure the downforce because it didn't matter. What mattered was setting it up to give us the fastest times, which is what we did. Beyond that we would have rebuilt it to be lighter and less expensive, but instead decided to change what arena we were competing in. So the spoiler got shelved until someone else wanted it for ESP.

Going back and testing it for absolute downforce numbers at different speeds would take three people most of a day, plus a set of fresh, or nearly fresh tires and site rental. All told, about $2500+. And what would we have? Data that showed it worked well between 20-70mph, and should be laid back if the expected speed range was 60-90mph. But that same conclusion was easily gained in about 20 minutes of testing without gathering the absolute downforce and just using a stopwatch (well, really a timing system). We just don't have downforce numbers for it.

 

[sheizasosay]

So...I picked up on maybe a point of confusion you have- a spoiler like this is the only rear aero that is legal for the autocross class I'm building the car for. A wing is probably better, but I can't use one. So, this is an example of a rules set picking your parts for you.

I am not confused. I don't have build rules. I do, however, look in autocross threads and at which mods might be worth money or not.

I have no idea how much it costs to make what you have. But if I did know, I might be considering how effective it is vs an APR200 wing or Gstream 800...etc. I know those prices and I know the possible downforce generations at varying speeds and at different AOAs.

I would think being very low, with a given spring rate and reduced suspension travel, that being on the bumpstops and having to increase the rate might be an indicator of downforce.

 

[Thinkkker]

This is an ESP car. You CANNOT run a wing. You are limited to the "stock" wing if you want that, or a spoiler not to fall outside the overhead view of the car and protruding more than 10" from the car in any direction.

Another words, you get a spoiler, that is 10" tall max.

This will make a difference. If you can shave off .001 of a second, that could be the winning time. So if it saves even thousandths it is worthwhile. I will give you seat of the pants feel update when I get mine done, but I have no sensors or anything to provide empirical data. I may bring out both trunks to an event to see what difference I can put down and double enter.

 

[claudermilk]

Well, we did test it. But we didn't measure the downforce because it didn't matter. What mattered was setting it up to give us the fastest times, which is what we did. Beyond that we would have rebuilt it to be lighter and less expensive, but instead decided to change what arena we were competing in. So the spoiler got shelved until someone else wanted it for ESP.

Going back and testing it for absolute downforce numbers at different speeds would take three people most of a day, plus a set of fresh, or nearly fresh tires and site rental. All told, about $2500+. And what would we have? Data that showed it worked well between 20-70mph, and should be laid back if the expected speed range was 60-90mph. But that same conclusion was easily gained in about 20 minutes of testing without gathering the absolute downforce and just using a stopwatch (well, really a timing system). We just don't have downforce numbers for it.

I certainly wasn't referring to you guys! I have no doubts that you tested extensively (and probably the most of anyone here).

I was referencing the "hey, I got a torque arm and it's AWESOME!" thread that turned into a typical S197Forum drama. Entertaining to lurk for sure.

 

[csamsh]

Welll you kind of were referencing them. It's their spoiler. I just bought it.

 

[mrgtx]

csamsh,
awesome thread! Thanks so much for sharing this...I'm just catching up and starting from the beginning.

Also as a Transformers fan from way back in the 80s..."Shockwave" is a great name for your car.