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PostPosted: August 28, 2011, 10:58 pm 
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I now have some large wings,1st time trying them and they feel good.Car is much more stable,continued the ftd perfect record but still need to find more speed as I suck on pax.

http://youtu.be/HNpzN9iLb2E


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PostPosted: August 29, 2011, 11:13 am 
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The voice of reason
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Looks like your fighting some understeer. Might start getting scary with much less though. Any thoughts on some traction for the front. How about one of those dirt track wings, now that would be big. You could mount it over the front roll hoop. If you put an access door on the endplate for it, it could have a lot of trunk space! Enough for a few bags of ice and 2 cases of beer perhaps or who knows what.

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PostPosted: August 29, 2011, 7:27 pm 
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I've been having understeer issues from day one,the wings definately helped both ends of the car and the rear wing is bigger than the front.Both wings were set at the ideal angle of attack for the event,for the next I'll reduce the rear angle for balance.Prior to the wings I've had issues with lots of oversteer on cold tires with the balance slowly shifting thruout the day to understeer,same basic thing happened with the wings but on a much smaller scale.
I've tuned the alignment to be about as good as it can be and won't spend any more effort untill I have new tires next spring(these hoosiers were bought used)-rememeber the old addage "thalt shall not chase old tires"


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PostPosted: August 29, 2011, 9:10 pm 
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Looks like the car is running really well.

Any details on the wings?

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PostPosted: August 29, 2011, 11:39 pm 
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Quote:
"thalt shall not chase old tires


yup, that makes sense. Looks like your having fun and the car is working well. Be fun to see what newer tires will do for you. I really don't know much about parking lot events, I think understeer probably comes with so many tight radius turns. Understeer can be very, very frustrating... With those turns being so quick, by the time you get rid of the understeer, you'll have too much oversteer it looks like, it will be intersting to see what you come up with...

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PostPosted: August 30, 2011, 5:15 pm 
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Wing details...umm friggan huge! :D

I get a picture up soon as I don't have any yet,the front span is 5'6" and the rear is 6' and both are the exact same profile with the chord being 2'.

When I was picking spring rates the math said stiffer springs in the rear,my experience is to have the driven wheels provide a little less of the total roll stiffness so I currently have the front with the higher wheel rate.With all the oversteer on cold tires I didn't dare stiffen it up,the wings greatly reduced the cold tire oversteer to nil with understeer being more the norm.I'll order some stiffer spring to have for the next event to test along with backing down the AOA of the rear wing.
I can't go softer up front due to areo load compressing the chassis too far.


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PostPosted: September 2, 2011, 3:49 pm 
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Action shot,
Image


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PostPosted: September 2, 2011, 4:34 pm 
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The voice of reason
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Those there are definitely wings alright! :rofl:

They look smaller in the vid...

If they aren't limiting you with rules you can put another front wing on several feet above the first one. It will start to make your competition all bug eyed which will be worth it alone. Sorry I have a hard time being serious sometimes...

There won't be much dirt on dust on the track after you go by... You can probably peel road kill off the pavement with that thing!

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PostPosted: September 2, 2011, 10:48 pm 
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Yep they look alot smaller in the wide angle vid,you can very much feel the load building with them.At the top of 2nd gear I get a very high frequency vibration which at 1st I thought the wings were vibrating the chassis or something.After a few runs I think its just my helmet in the wash of the front wing,sucks either way as its bad enough I can't see very well.
It does seem to get better with a little more speed though,at least it didn't get worse.

I was hoping for a vid from the sidelines to surface,buddies said it was definately sucking crap off the ground and displaying it behind the car on the 1st couple of runs.


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PostPosted: September 2, 2011, 11:28 pm 
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Location: Whitby, Ontario
It sounds like an oversized go-kart and goes like stink. Fantastic stuff!

I love watching that vid :)


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PostPosted: September 2, 2011, 11:31 pm 
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Tom17 wrote:
It sounds like an oversized go-kart and goes like stink. Fantastic stuff!

I love watching that vid :)



Thanks,your not far from Barrie-you should come on down for the next event.Sept 24th I think.


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PostPosted: September 3, 2011, 2:15 am 
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It's interesting that in that picture you can see the rear tire deforming from the cornering forces. Are you using the same size tires front and rear? THe rear is obviously ( I think ) carrying some more load because there is more weight in the rear. maybe you could use another pound of pressure there, but it seems understeer is more of the problem.

I sometime fought understeer in my FF, but was never sure if it was driving style or tires etc. Just wondered if I was afraid it would come around on me so unconsciously didn't pitch it enough going into corners. Just a subtle moment during the change from straight to cornering. I never quite got good enough that I could choose "Oh this time I'll over steer around and this time I'll understeer around...".

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PostPosted: September 3, 2011, 8:17 am 
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Yep same size tires front/rear,if I went to 10's on the rear I would really be in trouble trying to get it neutral.


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PostPosted: September 3, 2011, 8:53 am 
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Hmm, didn't know you were in Barrie. I may just have to come up some time. Do they have a class for unmodified shitty road cars? (Corolla lol) (Edit, just worked it out. $30 bargain! 25th Sept :). My helmet doesn't have the SNELL markings though as it's an RAC approved one. Bah, time for a new helm :( )

I notice your inside front is picking up a bit. I know nothing about how winged cars behave, so is that normal depending on setup or do you need more downforce on the front?


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PostPosted: September 3, 2011, 1:20 pm 
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I'm actually located in Huntsville,the Barrie club runs under the CASC autoslalom rules which are essentially the same as the scca rule set so there's a class for pretty much anything and everything.Also have loaner helmets if needed,they don't get to stressed on the helmet thing especially if your running in a stock class.
The only reason the inside front picked up is theres a crest to the lot right there,combined with the left rear compressed at turn in the front didn't have time to droop quick enough.We ran pretty much the same configuration but the opposite direction in the spring and the crest is a little sharper,at the speed I was carrying I had all 4 off the ground at that event(no wings to keep it loaded).


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