The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Just Some Aero Questions

Grant 302

basic and well known psychic
Your response was to a quote where the person mentioned my car.
No. We were talking about the actual racecar driver: @ajaquilante and the Phoenix cars. Oops...

I specifically mean your small canards (and only 2) for the ‘10-‘12 style. The OP of this thread has a 2011 GT. And even more so, that they are only the smaller ‘upper’ ones in your 4-piece design.

And checking the 2019 AI rules, small for the allowed size and quantity:

CC60A668-2E59-4737-ACFD-58C07F71D975.png


55E1F0E5-4FF7-45EB-AB36-B4EDDCD03127.png

So the OP would, like I said, be better off spending the money elsewhere. Either from another shop like @EIGHTLUG ’s or with somebody else that makes 4 that fits his model year.
 
Last edited:
No. We were talking about the actual racecar driver: @ajaquilante and the Phoenix cars. Oops...

I specifically mean your small canards (and only 2) for the ‘10-‘12 style. The OP of this thread has a 2011 GT. And even more so, that they are only the smaller ‘upper’ ones in your 4-piece design.

And checking the 2019 AI rules, small for the allowed size and quantity:


So the OP would, like I said, be better off spending the money elsewhere. Either from another shop like @EIGHTLUG ’s or with somebody else that makes 4 that fits his model year.
Not sure if that was meant to be snarky, but I know him as Andrew. And yes, he's an extremely good driver.
As for canards, the 1.5" beyond the max track with rules is what we had to fit in. But what you are forgetting is that over the last few years, the track width for older cars has been widened, thus technically allowing for wider canards now, but not when we originally made them. So I'm not sure where your going with all this, but the OP was asking about canards. Not sure what you mean by he would be better spending money elsewhere. That depends what the OP is aiming to achieve.
 
42
21
Exp. Type
Autocross
Exp. Level
Under 3 Years
Tennessee
That depends what the OP is aiming to achieve.
Right now, I am just trying to get some starting mods done, like wheels/tires, some suspension stuff, and then I'll move some into the aero. So this was made for a kind of future plans thread. In regard to Grant's comments, at this moment yes, my money would be better spent elsewhere. However, eventually I will likely invest in canards, but I just wanted to get some outside opinions on aero in general, as well on the possibility of functional custom canards. Regardless, thank you AJ for the information you've given, it has been very helpful.
 
Right now, I am just trying to get some starting mods done, like wheels/tires, some suspension stuff, and then I'll move some into the aero. So this was made for a kind of future plans thread. In regard to Grant's comments, at this moment yes, my money would be better spent elsewhere. However, eventually I will likely invest in canards, but I just wanted to get some outside opinions on aero in general, as well on the possibility of functional custom canards. Regardless, thank you AJ for the information you've given, it has been very helpful.
Understood and you're welcome. I was going off your original post and I do agree with Grant to an extent where a wing would be the next best move if you build, or install a splitter. But since you mentioned you weren't on board with a wing and dealing with the "ricer" comments, makes me feel you already understood a wing would be a good match with a splitter and added comments based on your canard questions. As for canards, after the splitter and wing cancel out the lift generated by the rest of the car, it may make 200ish lbs of Df (on a small flat splitter and decent wing with very little angle). So even if canards added 20-40lbs of Df at 100, that a 10-20% bump in Df from such a small device. And a front shift in Df on a nose heavy mustang is always a good thing. Edit: For example, on the E36 in the wind tunnel, adding canards provided almost a 15% forward shift in downforce since the total downforce was fairly low. Adding canards to my car, since the splitter alone made almost 800lbs of Df, the actual raw Lbs of Df generated was close to the E36, but only resulted in about a 2% forward shift in downforce. This also kinda highlights why just throwing out a raw Df number may be misleading.
 
Last edited:

Mad Hatter

Gotta go Faster
4,506
3,199
Santiago, Chile
Hmm.... Lets put it in very simple terms for people like me... A Splitter/Wing combo. really is a big deal.... Once you decide to really track the car and your rules allow it... If that is true. you no longer care about the Ricer comments... Actually, a modified mustang is hard to call ricer since the looks and sounds are so serious.

hmm, maybe not....the ricer Mustang thing that reminds me of the last time we were visiting the kids in Vancouver. Saw a 2013 mustang parked and it had a wide body with some big wheels... As I went over to take a look, it was a automatic V6 with a stock exhaust.... I guess you can have a ricer Mustang!!

DISCLAIMER: No derogatory or demeaning intent to those owners of non V8 cars was either intended or implied.
 
533
361
sfo
AJH,

Can you comment on splitter and canard location or shape and how the 2 work together?

Can you comment on general wickerbill heights like is there a relation between WB height and chord length or can this only be found in the wind tunnel?
 
AJH,

Can you comment on splitter and canard location or shape and how the 2 work together?

Can you comment on general wickerbill heights like is there a relation between WB height and chord length or can this only be found in the wind tunnel?
Canards will create a lower pressure zone in the wheel well by forcing are up, over, or around the tire and tire opening. This low pressure zone now wants to be filled and will allow air to travel under the splitter easier (yes, some will come from other areas like the engine bay and we’ve actually seen increases in the pressure drop across a radiator from canards in the wind tunnel as well) thus allowing the splitter to make more downforce. Canards themselves don’t make much downforce, but how they affect the air as a whole allow the whole package to work better.
the general rule of thrum for gurneys on wings is 2-5% of cord length. Yes, taller may create more drag but at a much less efficiency. I’ve seen a 1/2” tall gurney in the wind tunnel add 15lbs of Df to one wing in the wind tunnel, and the same 1/2” gurney add 110lbs to another wing!
 
Interesting AJ. So could it be a safe-ish generalization to say that canards can (if designed well) also increase the effectiveness of splitter tunnels (if designed well) since they decrease wheel well pressure and a tunnel can then vent into the wheel well more easily?
 
Interesting AJ. So could it be a safe-ish generalization to say that canards can (if designed well) also increase the effectiveness of splitter tunnels (if designed well) since they decrease wheel well pressure and a tunnel can then vent into the wheel well more easily?
Yeah, I think that would be a decent assumption that canards would have a greater affect on a tunneled splitter than a flat splitter.
 

Grant 302

basic and well known psychic
Canards will create a lower pressure zone in the wheel well by forcing are up, over, or around the tire and tire opening. This low pressure zone now wants to be filled and will allow air to travel under the splitter easier (yes, some will come from other areas like the engine bay and we’ve actually seen increases in the pressure drop across a radiator from canards in the wind tunnel as well) thus allowing the splitter to make more downforce.
C’mon. The ones you make for the 2011 aren’t big enough or shaped or located to do any of that. Doesn’t seem to me you address bob’s question at all.

As for any vorticity...what vortex? Yours aren’t actually shaped for it and basically function as a mini little winglet. Clearly seen in the lack of AoA in any sense. And then not moving enough mass to influence any flow much less to even create any coming out of the wheel well.

Canards themselves don’t make much downforce, but how they affect the air as a whole allow the whole package to work better.
Fudge... Some canards do actually make significant downforce as independent devices, without consideration of downstream and secondary effects.

Basically, the canards in question don’t do much on even a high speed straight. And they do even less in a turn when adding yaw. The one on the windward (inside) side of the turn loses the most downforce of the two. A good design would make more.
 
C’mon. The ones you make for the 2011 aren’t big enough or shaped or located to do any of that. Doesn’t seem to me you address bob’s question at all.
I addressed bobs question on the interaction of the relationship between canards and splitter.
As for any vorticity...what vortex? Yours aren’t actually shaped for it and basically function as a mini little winglet. Clearly seen in the lack of AoA in any sense. And then not moving enough mass to influence any flow much less to even create any coming out of the wheel well.
Please, share what data you have to prove or disprove your claim. Not sure if you are aware, but as you call them a winglet, due to the pressure differential, a vortex is created. I have several run photos of our canards with wool tufts in the wind tunnel producing these vorticies that you claim down exist on ours. Also, seems like you are not taking into consideration that the low pressure created by the splitter draws air in a downward angle along the side of the bumper. A simple oil drop test can show this on anyones car with a splitter. So the physical angle of the canard isn't quite as important as the interaction of the oncoming air and canard.
Fudge... Some canards do actually make significant downforce as independent devices, without consideration of downstream and secondary effects.

Basically, the canards in question don’t do much on even a high speed straight. And they do even less in a turn when adding yaw. The one on the windward (inside) side of the turn loses the most downforce of the two. A good design would make more.
Yes, some canards do. But you gotta consider rules, manufacturing time and complexity, and just the sheer size of them, costs, and the fact that not everyone wants, or needs a huge set of canards on the front of their car. As I mentioned in earlier posts, if a splitter is allowing the front of a car to make 100lbs of Df (about a reasonable claim based on the wind tunnel tests I've ran with cars with flat splitters) Then a small pair of canards making 20lbs of Df, is still a 20% forward shift in aero balance. Thats still significant. Everyones wants and needs are different. There is no one universally perfect size.

Now I know Grant will read these and have issues with them while still not bringing any of his own CFD, wind tunnel data, or personal experience to the table to rebut mine.
 
151
136
Guys, sorry for a slightly different topic but the OP kindly invited any aero questions:

Do the stock 2012 Boss front aero upgrades (lower front fascia and small "splitter," street version, not the LS front splitter) make any noticeable difference in cooling, fuel mileage, or high speed stability compared to a stock 2011 GT?

I have a 2011 GT with the standard fugly lower front fascia and the little oem ducktail style rear spoiler.

Honestly I might do the Boss upgrade regardless just because it looks so much better. But I'm interested if there is any actual science behind the idea.

Thanks for any insight.
 
Guys, sorry for a slightly different topic but the OP kindly invited any aero questions:

Do the stock 2012 Boss front aero upgrades (lower front fascia and small "splitter," street version, not the LS front splitter) make any noticeable difference in cooling, fuel mileage, or high speed stability compared to a stock 2011 GT?

I have a 2011 GT with the standard fugly lower front fascia and the little oem ducktail style rear spoiler.

Honestly I might do the Boss upgrade regardless just because it looks so much better. But I'm interested if there is any actual science behind the idea.

Thanks for any insight.
Noticeable difference is relative. A very experienced driver in tune with his car would notice it in high speed handling. A first time DE person, probably not. Cooling is probably relatively un changed. Drag will go up a tad. Not sure what you mean by the science behind it but the data behind a splitter and spoiler making downforce has been around for ages. So since it was lumped into one question, if your goal was more Df and a more stable car at speed, yes, run them. If its fuel mileage, I'd say keep them off. Or if you just plain like how it looks, then put them on.
 
Last edited:
151
136
AJ, thank you for the response, makes perfect sense.

When I referred to "actual science," I wasn't questioning the basic science behind splitters and wings. I only meant, is there evidence the Boss aero upgrades are significant enough to be noticeable in any meaningful way. Which you answered.

Thanks for your help, appreciate it.
 
Here is my lowered splitter after I completed fabricating a foam spacer with 1/16 ABS sheet stock covering all the exposed areas. I also installed aluminum tube columns in the foam to prevent compression. I may add a small deflection "wing" for forcing air into the oil cooler which is right behind the lower grille opening. The splitter is now 3.5 inches off the track surface. Also added in the 4 inch intakes for brake cooling while I had the front end apart.

IMG_7452.jpg

IMG_8169.jpg
 
5,331
6,076
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Here is my lowered splitter after I completed fabricating a foam spacer with 1/16 ABS sheet stock covering all the exposed areas. I also installed aluminum tube columns in the foam to prevent compression. I may add a small deflection "wing" for forcing air into the oil cooler which is right behind the lower grille opening. The splitter is now 3.5 inches off the track surface. Also added in the 4 inch intakes for brake cooling while I had the front end apart.

View attachment 63978

View attachment 63979
Now that's a damn clean way of doing it.
 

JDee

Ancient Racer
1,480
1,483
Exp. Type
W2W Racing
Exp. Level
20+ Years
halfway between Mosport and Shannonville
Nicely done piece, looks very pro made. One of the easier looking ideas for a splitter than I've seen yet.
Nice shop!
And that sled, what's with that? Snocross? Brings back memories from a long time ago when I had a healthy back. Maybe that's why I don't have such a healthy back now that I'm about to enter my 7th decade? LOL!

What are you doing for fasteners for the undertray? Are you using the stock locations for fasteners?
 

TMO Supporting Vendors

Latest posts

Buy TMO Apparel

Buy TMO Apparel
Top