Race Tracking Your Supra - Information exchange

[TBK]

I just keep a tire chalk and a probe pyrometer with me and decide based on that and the way it feels out on track-I figure out what I want for myself. It’s probably overkill a lot of the time but it’s what I am doing. I do the same thing with my alignment. Lots of really smart people on here do it in ways that work for them but I found I have my own preferences. For example, I like -3.3 degrees of camber and listen

I usually set my cold temps to try and hit the manufacturer’s recommended warm temps at first with a new to me tire and adjust from there. If I feel the tire folding during cornering after the out lap I need more air/undershot it, and if grip drops off before I expect it to I need to let some out. I will make quick pit stops to make those adjustments and dial them in. Once I get it dialed I write it all down and adjust my cold temps to hit my own targets.

I started paying more attention to manufacturers recommendations last year when I tried out the Hoosier TAPs. It seemed like a lot of us were having wear issues with that tire, and even delamination-both of which I experienced. I attributed it to the fact that I DID NOT follow the recommended curing process.

I gave them another shot and followed the instructions and they worked great for like five weekends and then they were bald.

Nankang recommend 34-40 PSI for anything over 3,050lbs. So if we were to go by their reco, we'd be in the 36-38psi range, which def won't work for me.

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[zackarybyrd]

Nankang recommend 34-40 PSI for anything over 3,050lbs. So if we were to go by their reco, we'd be in the 36-38psi range, which def won't work for me.

and I guarantee you know what works for you better than I do, and I’ve never run the nankangs (probably should have!) but if I did, the first time out after the cure I would be targeting 36psi and figuring out what I wanted from there. I also fully endorse doing whatever razorlab says pretty much every time and then adjusting for your own purposes.

 

[razorlab]

Pressures will def be setup,track, ambient temp, and even tire dependent. I run about -3.9/4.0 front camber. My main local track is 98% right turns and I run RE71RS's as my main tire.

 

[Vegas17]

Has SPL solved their bearing issues? Are we still recommending verkline or others now? I'm at the point of needing more camber than the Verus plates and stock concentric rears.

 

[TBK]

Posted this in my build thread, but nobody checks my build thread, so trying here....


i've been going back and forth with both AJ Hartman and Zebulon to eventually replace my wing.
Specs:
Current: APR: 67" length - 10" chord w/APR gurney flap & Singular Motorsports Endplates
AJ Hartman Fulcrum 14: 72" length - 14" chord
Zebulon ZWG-330: 72" length - 12.9" chord

Anybody have an experience working with either of AJ Hartman or Zebulon. Any wisdom to share here? The car will slowly move up a few classes, so i'm not too worried about balancing the front, which tbh already has a strong base. Bigger tunnels would be next perhaps. Plus i'd be able to run a low AoA for now, which would be nice.

As it stands, i'm kinda, but barely leaning more towards the Fulcrum 14. Simply put, more downforce. Yes, along with that comes more drag, but drag is a lot less important on a time attack car than it is on an endurance car. Time attack cars generally have ridiculous amounts of power, which yeah doesn't nullify the drag obviously, but largely offsets the penalty in ways endurance built cars can't. Well before i'd have the wing anyway i'll be running a conservative 720whp or so on PI.

I don't know enough about the design philosophy differences when it comes to their airfoils. I do however like the theory behind Zebulon's dynamic AoA vs the static one that AJ Hartman has. I think a 2D approach has a higher floor, but a 3D one, assuming it's designed for a specific application, has a higher ceiling. Not an expert though, so i'm hoping someone can chime in.

 

[i3igpete]

Based on just visual checks, the zeb wing has more curvature, which means it likely has the similar DF at max AoA as the AJH, despite the smaller chord.

I have never worked with zeb but the vibe i get is that they are very responsive, but you will pay for that response time. Thats their main strength though, quickly iterating on bespoke/custom stuff.

AJ is very helpful but he's just one dude juggling everything.

 

[TBK]

Based on just visual checks, the zeb wing has more curvature, which means it likely has the similar DF at max AoA as the AJH, despite the smaller chord.

I have never worked with zeb but the vibe i get is that they are very responsive, but you will pay for that response time. Thats their main strength though, quickly iterating on bespoke/custom stuff.

AJ is very helpful but he's just one dude juggling everything.

Is that image legit? Where's it from? the Fulcrum 14 looks a lot flatter than that in pics. I could be off though obv since they're just pics

By "pay for it" do you mean literally? Because they seem to be priced similarly

 

[Traxion]

I've got my Fulcrum 14 laying against my wall with the endplates off. I can send a side profile pic of the airfoil tonight when I get home to confirm if nobody else does first.

 

[PowerGetter]

I have worked with both AJH and Zebulon and have no complaints about either. Both companies are very responsive, however Zebulon typically having longer lead times for anything thats custom or not readily available off the shelf (universal stuff).

You can't go wrong with either one of them, but in terms of design your class specific rules will dictate the best approach for your car. At the end of the day, it's about the chord length, span (the bigger, the better), and position of the wing.

 

[TBK]

I've got my Fulcrum 14 laying against my wall with the endplates off. I can send a side profile pic of the airfoil tonight when I get home to confirm if nobody else does first.

That'd be cool thanks man. So why'd you choose the Fulcrum 14 over the Zeb 330?

 

[i3igpete]

Seems about right to me. Screenshot was from the occams aero discord

.

At the end of the day, it's about the chord length, span (the bigger, the better), and position of the wing.

Yep, given a known profile, the 3 tuning knobs you have are span, chord, and AoA.

Increasing span always improves overall efficiency. Always max this first.

AoA has significant drag penalties. Always adjust this last.

This leaves chord as your middle knob.

 

[Traxion]

That'd be cool thanks man. So why'd you choose the Fulcrum 14 over the Zeb 330?

I didn't really cross shop Zebulon. AJ had 10% off for Supra's when I bought so that was a big chunk off and I knew it'd be able to put out more downforce than I could reasonably counter balance with front aero. Also the styling was exactly what I was looking for. I do feel a little good about supporting a real small business 1 man shop as well.

 

[TBK]

I have worked with both AJH and Zebulon and have no complaints about either. Both companies are very responsive, however Zebulon typically having longer lead times for anything thats custom or not readily available off the shelf (universal stuff).

You can't go wrong with either one of them, but in terms of design your class specific rules will dictate the best approach for your car. At the end of the day, it's about the chord length, span (the bigger, the better), and position of the wing.

I agree that bigger is better, but that's also when comparing identical airfoils. I don't know how much difference the airfoil itself makes, but I'm fairly certain it accounts for something. Not necessarily just in total downforce, but maybe the downforce curve, L/D etc...

Seems about right to me. Screenshot was from the occams aero discord

View attachment 152008 . View attachment 152009

Perfect shot

 

[i3igpete]

I don't know how much difference the airfoil itself makes,

The Airfoil is everything. In a perfect world, with an infinitely long wing, the 3D results will converge to the 2D. The 2D simulation is the upper limit of performance. AFAIK, a 3D CFD run or wind tunnel can only approach the 2D simulation results. If your 3D CFD run outperforms the 2D, something was set up wrong.

You are either scaling that number up (chord and span) or attempting to converge the 3D towards the 2D (endplates, wing stands).

 

[Subydude]

I've talked to and raced with the Zebulon guys. It's a very nice setup, and worth the cost if you're pushing the envelope. AJ Hartman has also run locally at various time trials/time attacks I run at and his stuff also works well. I haven't chatted with him though, so no real comment there.

I can say my plan over the next few years is to buy the Zeb package for my autox car and then gift it's Ciro wing to the track car.

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