GTC-200 wing, smaller wing or no wing at all?

[Matt93SE]

Originally Posted by GrandSport

No data, but I'd strongly assume the outsides are very hot, lol

It's set to minimum A0A.

Originally Posted by CSG Mike

I bet you can go "more" minimum.

You literally want the leading edge to be slightly higher. Give it a shot, maybe 2 degrees negative.

Digging this one up a bit cause I haven't seen closure yet and trying to help a lil.

Can you post photo of the wing mounts/adjuster?

on both of the APR wings I've owned, the hex tube adjuster was too long to get to the correct AOA, so I had to trim it down a bunch. I think I cut 3/4" off the universal bracket kit on my 240SX, and maybe 1/2" on the one for my FRS and I'm just now about +1 or +2deg AOA.

[lutfy]

Originally Posted by GrandSport

So I need to get a new setup on the car. I'm wearing the outsides of V730s in about 5 hours and the insides are at 80%. No idea what happened, but it's both sides and there is a lot of negative camber.

While I'm getting a setup done, I'm debating removing the rear wing entirely or just going to smaller one (if that's possible). I see ARP has deferent side plates, but they dont state how much of a difference they make. If it's a big difference, for $120, I'd start there (they also dont tell us the difference between the old, the new and the euro side plates)

It just pushes too much as it is, and I can't get much, if any, rotation on braking.

As far as running ST5, or similar, what is the consensus for a wing- if there is one?

Been running APR since 2017. Ran both the 300 and 200 rear wings. The 2D with gurney flap was marginally faster (2/10 at Dominion) but hard to decipher the difference.

The 2D wing can go down on AOA by the way. My best result was -3 degrees but since they are chamfered and will still produce downforce.

Past 5 years have been on the 2D wing running 0-degree AOA with a gurney flap. Standard side plates that came with the kit. Hope this helps.

Lutfy

[Matt93SE]

Another thing that comes across my mind is ride heights and roll center. Any pics of your car on track? how's the body roll?

If you are still on stock control arms and have the car lowered enough, you put the roll center below the car's center of gravity and then it leans like a pig in the turns. all that negative camber goes away when the whole car is leaning.

[dragoontwo]

Originally Posted by Matt93SE

Another thing that comes across my mind is ride heights and roll center. Any pics of your car on track? how's the body roll?

If you are still on stock control arms and have the car lowered enough, you put the roll center below the car's center of gravity and then it leans like a pig in the turns. all that negative camber goes away when the whole car is leaning.

For the roll center, what is lowered enough in your opinion?

[Matt93SE]

Originally Posted by dragoontwo

For the roll center, what is lowered enough in your opinion?

There are hard numbers for all this, but I'm just an electrical engineer and play with security systems, not CAD and geometry. it's not that hard tho.

essentially, look at the angle of the control arm inner pivot to the pivot in the ball joint. if that is past horizontal and pointing "up" from inside to outside, then you have roll center problems. with most street cars, that's roughly around 1-1.5" lower than stock, but I've never actually done the measurements and maths on a Twin. it's likely that some of the more academic racers have done it.

I just knew my car handled like crapola and was understeering with tire wear issues and I couldn't get enough camber in the car to reduce the front wear. Sooo I put on a set of SPL arms with roll correction about the same vertical offset as my lowering, then reset the bumpsteer. next race I went 2 seconds faster on the same track and had WAY better turn in response and tire wear.

can't help with much more specifics than that cause it was 2 yrs ago.

[NoHaveMSG]

Originally Posted by Matt93SE

Digging this one up a bit cause I haven't seen closure yet and trying to help a lil.

Can you post photo of the wing mounts/adjuster?

on both of the APR wings I've owned, the hex tube adjuster was too long to get to the correct AOA, so I had to trim it down a bunch. I think I cut 3/4" off the universal bracket kit on my 240SX, and maybe 1/2" on the one for my FRS and I'm just now about +1 or +2deg AOA.

Had the same issue with mine. Can’t remember what I trimmed off of them.

[RedReplicant]

Originally Posted by dragoontwo

For the roll center, what is lowered enough in your opinion?

Below 140mm front pinchweld to ground, per 949

[jflogerzi]

Soon I should have APR GTC Wing on, Verus Splitter, end plates and dive planes installed with track spec hood vents. Springs will be 7K front/8K rear on RCE T2s. I will report progress and performance at a variety of tracks

[Bergycheese348]

FWIW V730s are known to like less camber than a traditional setup due to their super stiff sidewall. I forgot where I read that specifically, but to me it is apparent because I have so much wear on the inside and very very little on the outside. Camber was -3.5 front and -2.5 rear, rear was fine but going to -3 front this year.

My setup consists (at that time) TRD lip, skirts, canards. Verus UCW (mid to full AOA), hood vents, diffuser, spats. APR splitter (for the TRD lip) that is properly flat. AST 5100 suspension with 6k/6k Swift springs. TRD RLCA, toe arms, trailing arms. I have a few other things to predominantly reduce drag too, but that isnt as important in this discussion.

By no means am i a specialist in any of this, this is just what I have concluded based on what I have found and what I have experienced.

[GrandSport]

Originally Posted by Bergycheese348

FWIW V730s are known to like less camber than a traditional setup due to their super stiff sidewall. I forgot where I read that specifically, but to me it is apparent because I have so much wear on the inside and very very little on the outside. Camber was -3.5 front and -2.5 rear, rear was fine but going to -3 front this year.

My setup consists (at that time) TRD lip, skirts, canards. Verus UCW (mid to full AOA), hood vents, diffuser, spats. APR splitter (for the TRD lip) that is properly flat. AST 5100 suspension with 6k/6k Swift springs. TRD RLCA, toe arms, trailing arms. I have a few other things to predominantly reduce drag too, but that isnt as important in this discussion.

By no means am i a specialist in any of this, this is just what I have concluded based on what I have found and what I have experienced.

Man, I'm nowhere near wearing the inside of my 730s before the outside with the same -3.5

[Bergycheese348]

Originally Posted by GrandSport

Man, I'm nowhere near wearing the inside of my 730s before the outside with the same -3.5

That is what is strange and what makes me think you might have a different issue. I daily the car so I understand there would be more wear on the inside, but to the extent I have it is clear I am running too much camber for the setup. 5k miles, three track days, and two autocross events and the fronts are toast on the inside. Rear at -2.5 looks like almost perfect wear to me

[DocWalt]

What's your toe? Inner edge wear is almost always from toe and not camber.

[RedReplicant]

Get out the pyrometer....

[GrandSport]

Originally Posted by DocWalt

What's your toe? Inner edge wear is almost always from toe and not camber.

A hair over zero. It's pretty close to zero.