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Just Some Aero Questions

41
20
Exp. Type
Autocross
Exp. Level
Under 3 Years
Tennessee
Hey, all! I've been doing some research, planning out my budget for my car, and have decided that instead of trying to find a legitimate, OE Laguna Seca or World Challenge splitter for, I don't know, just south of $1,000, I'm going to make a custom "knock-off" one myself. Now, I have found a thread on this and know what all I need to construct it, but I do have one question for all you Boss folks out there.

Can you use the OE LS splitter rods while using the Boss street splitter as a spacer? I'm trying to judge what length I would need, if another length was needed.

Now onto canards. I know AJ Hartman is, as far as I know, king. I was wondering if anyone had ever attempted to create custom canards (if they would even work?), or if there were any other companies I should look at.

Any opinions welcome, just trying to understand the world of aero a little better. Thanks!

P.S. Yes, I know I left out wings, my car is still primarily a daily driver, and I don't have the energy to deal with all the "RICER!!!" cries I would inevitably deal with. If anyone wants to talk about wings, feel free to. This is not meant to be a just "me" thread, it's for anyone and everyone with aero questions.
 
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4,052
I hate to tell you this, but having built quite a few custom spoilers, splitters and wings, I've discovered that by the time you finally get them done, you are pretty close to the cost ( but a lot more effort) of a decent store bought unit.
Unless it's a custom design, it's usually simpler to buy one, or try and buy a
" flawed" one from the mfg.
 
41
20
Exp. Type
Autocross
Exp. Level
Under 3 Years
Tennessee
I hate to tell you this, but having built quite a few custom spoilers, splitters and wings, I've discovered that by the time you finally get them done, you are pretty close to the cost ( but a lot more effort) of a decent store bought unit.
Unless it's a custom design, it's usually simpler to buy one, or try and buy a
" flawed" one from the mfg.
Thank you for letting me know, I'd never heard that before. One of the main problems I'm running into is that I really love the look of the LS/WC splitter, and I think most people do, so they're really hard to find. Plus, no one has any of the OE ones left in stock, so building made the most sense to me. I'll keep an eye out for one that may pop up, but I think it would be pretty cool to build something of your own and be able to recreate it if it breaks, too.
 

Grant 302

basic and well known psychic
The bolt pattern is different for the ‘11-‘12 parts from the ‘13-‘14. I wouldn’t use the base Boss splitter as a spacer. The bottom is contoured enough to make for problems if you try to do that. It can, however, make a good template to cut your own out of another material like plywood or ABS (many disagree) like OEM.

Now onto canards. I know AJ Hartman is, as far as I know, king.

For the money, I say pass. His are too small to do much of anything. Better off putting the same money toward a vented hood or the wing or fender vents or brake deflectors or just about anything else first.

And I’d plan your wing before anything else. JMO.
 
3,965
4,052
A general rule of thumb is to match the splitter/ wing combo, either run the old style grand am splitter/ wing, or the PWC splitter /wing since both of those were developed in a wind tunnel, same for the current gt4 spec parts. They all need to be used in pairs to keep the balance correct
 
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sfo
They all need to be used in pairs to keep the balance correct

...or yet one more thing to develop. I also think if you are just adding the spitter and no ricer wing what's the point? If the splitter worked then you need the wing. If the splitter doesn't work then you just don't need to carry it around. Personally, I'm very happy to not be in an aero race class. A bunch of us racing vettes vacated T1 for NASA ST2 adding wings and things. After each person went gardening and ripped off their $500+ splitter the norm became plywood spares in your trailer spray painted flat black. I was the only guy to move to T2 skipping aero and a bunch of new development drama. Yes...I am lazy.
 
41
20
Exp. Type
Autocross
Exp. Level
Under 3 Years
Tennessee
...or yet one more thing to develop. I also think if you are just adding the spitter and no ricer wing what's the point? If the splitter worked then you need the wing. If the splitter doesn't work then you just don't need to carry it around. Personally, I'm very happy to not be in an aero race class. A bunch of us racing vettes vacated T1 for NASA ST2 adding wings and things. After each person went gardening and ripped off their $500+ splitter the norm became plywood spares in your trailer spray painted flat black. I was the only guy to move to T2 skipping aero and a bunch of new development drama. Yes...I am lazy.
Lazy, but saving money I suppose! Thanks for the input. Maybe an unpopular opinion, but for me, at least to some extent, "show" has always been relatively close to "go", and I personally love the look of some aero. I do understand, though, that only having one half of the setup will limit its functionality, but I eventually hope to (maybe) race st2 and tt2 once I can afford to convert to an entirely track car.
 

Norm Peterson

Corner Barstool Sitter
939
709
Exp. Type
HPDE
Exp. Level
5-10 Years
a few miles east of Philly
Any opinions welcome, just trying to understand the world of aero a little better. Thanks!

P.S. Yes, I know I left out wings, my car is still primarily a daily driver, and I don't have the energy to deal with all the "RICER!!!" cries I would inevitably deal with. If anyone wants to talk about wings
As blacksheep and bob have already noted, you need to either do both the splitter and the wing or neither.

The reason is, as also noted, aero balance. What I'm going to add is that an effective splitter and no wing has some potential for making the car "aero-loose", which would tend to get worse as speeds rise - an effective splitter works to unload the rear tires by turning the front axle line into a soft fulcrum. Oversteer in a high speed kink sounds like a whole lot more excitement and a whole lot less fun than tailhappiness in a tight hairpin . . .

IIRC, Terry Fair of Vorshlag ran into this exact issue a few years during development of the rather fast red S197. I'm sure it's included in the car's build thread either here or on another forum or on Vorshlag's own forum.


Norm
 
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Mad Hatter

Gotta go Faster
4,104
2,657
Santiago, Chile
Throwing my 2 cents in the ring...... Adding the larger splitter was not a huge change.... Adding the big wing and the splitter was truly something else... thinking about it, probably one of the biggest changes in the cars handling. Still learning to get on the gas earlier then before the wing... been conditioned after all those wingless years too having the rear break away easily. Now its far far more stable.
 
41
20
Exp. Type
Autocross
Exp. Level
Under 3 Years
Tennessee
Throwing my 2 cents in the ring...... Adding the larger splitter was not a huge change.... Adding the big wing and the splitter was truly something else... thinking about it, probably one of the biggest changes in the cars handling. Still learning to get on the gas earlier then before the wing... been conditioned after all those wingless years too having the rear break away easily. Now its far far more stable.
Yeah, just to clarify I never doubted the effectiveness of a wing. I very much look forward to having one. My only issue, per say, is that I dont think my car will see enough track use over the next few years to justify spending around $1500 for a wing (probably 5 or 6 events a year? I dont like the idea of crashing my only car). So, I guess my plan would be better expressed as being in steps. Splitter first, wing later was my philosophy, but I do understand why people recommend doing both at the same time.
 
623
854
Exp. Type
Time Attack
Exp. Level
Under 3 Years
SoCal
Yeah, just to clarify I never doubted the effectiveness of a wing. I very much look forward to having one. My only issue, per say, is that I dont think my car will see enough track use over the next few years to justify spending around $1500 for a wing (probably 5 or 6 events a year? I dont like the idea of crashing my only car). So, I guess my plan would be better expressed as being in steps. Splitter first, wing later was my philosophy, but I do understand why people recommend doing both at the same time.

For a car that’s primarily street driven, I would find a salvage trunk lid to mount the wing to and swap for track days. The larger wings create enough downforce the sheet metal is going to get warped, so might as well be on a donor lid. Then you don’t have the annoyance of a-holes trying to drag race you at every stop light with the stock lid back on for the street.
 

Mad Hatter

Gotta go Faster
4,104
2,657
Santiago, Chile
Yeah, just to clarify I never doubted the effectiveness of a wing. I very much look forward to having one. My only issue, per say, is that I dont think my car will see enough track use over the next few years to justify spending around $1500 for a wing (probably 5 or 6 events a year? I dont like the idea of crashing my only car). So, I guess my plan would be better expressed as being in steps. Splitter first, wing later was my philosophy, but I do understand why people recommend doing both at the same time.

I am a cheap bastard! My Wang was 900 bucks from 9livesracing.com
 

Grant 302

basic and well known psychic
Adding the big wing and the splitter was truly something else...
And how long did I nag you to do it?

But you should also say that you run in an unrestricted aero class. So of course you should run one and as much aero as your wallet can essentially handle and clears the public roads there.

bob isn’t wrong for running no aero in a restricted class.

Just gotta make it right for whatever you’re doing with the car, driver preferences, and ability to tune the car suspension wise.
 
41
20
Exp. Type
Autocross
Exp. Level
Under 3 Years
Tennessee
For a car that’s primarily street driven, I would find a salvage trunk lid to mount the wing to and swap for track days. The larger wings create enough downforce the sheet metal is going to get warped, so might as well be on a donor lid. Then you don’t have the annoyance of a-holes trying to drag race you at every stop light with the stock lid back on for the street.
Yeah, when I do get a wing, that was actually my plan. I found multiple for around $200 or so, but glad to hear that its not a crazy idea, though.

I am a cheap bastard! My Wang was 900 bucks from 9livesracing.com
Well, shoot. I guess I've been looking at the wrong websites! Ill be sure to check that site out. Quick question on that, though, is there a "hierarchy" of wings? Are there any brands to avoid at all costs, or are most of them pretty good quality?
 

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