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Just Some Aero Questions

Ludachris

Chris
Staff member
Moderator
1,411
1,617
Exp. Type
HPDE
Exp. Level
5-10 Years
Newcastle, CA
Went through and did some thread clean up. Let's keep the debates civil, constructive, and most of all, respectful. Grant, you obviously have some strong opinions about AJ and the design of his canards (and other products). Seems like you make a point to rebuke nearly anything and everything he posts and bring constant attention to perceived design flaws in his products. Not sure why or what the history is there, but please do us all a favor and tone down the passive aggressive tone - both towards other members and towards TMO in general. It might even be beneficial to put AJ on your ignore list too.

Anyone can use the Ignore feature. Just hover over the username of the person (or their avatar) and you'll see an Ignore button - click that and you won't have to see posts from that person in the forum anymore:

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Any issues with this thread cleanup, you guys are welcome to PM me so as to not take this thread off topic again.
 

Grant 302

basic and well known psychic
Please note everything, and I mean EVERYTHING, was civil, factual, and good and all...until AJH showed up. But it’s always nice to be singled out as the Troublemaker. Just sayin’.

Thanks for the cleanup. 👍
 

Ludachris

Chris
Staff member
Moderator
1,411
1,617
Exp. Type
HPDE
Exp. Level
5-10 Years
Newcastle, CA
Please note everything, and I mean EVERYTHING, was civil, factual, and good and all...until AJH showed up. But it’s always nice to be singled out as the Troublemaker. Just sayin’.

Thanks for the cleanup. 👍
This is the perfect example of a reply (with another jab mixed in) that is certain to take it back off topic, hence my request to have people PM me about it instead of replying here.

Let's keep replies on the topic of aero from here on out please.
 
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
Not a bad solution at all! Good stuff. Would love to hear your follow up once you get it out or if you have any data to compare to.
 
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?
That sled is a Yamaha Sidewinder XTX SE. 1000cc 4 stroke Turbo with 265HP. Makes the winters go by faster. Literally. A great trail sled northern Minnesota and UP of Michigan.
As for the fasteners I am using countersunk head 1/4-20 X 3 SS through all the locations typically found in the stock splitter and lower bumper fascia. Think there is about 20 of them and holds everything from the undertray through the new foam spacer. Added the large countersunk washers from this go-kart place www.kart-master.com
Along with the 4 rods mounted into metal the splitter is pretty sturdy. I think I am going fabricate some brackets at the rear to further support it.

IMG_8171.jpg
 
5,141
5,663
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
That sled is a Yamaha Sidewinder XTX SE. 1000cc 4 stroke Turbo with 265HP. Makes the winters go by faster. Literally. A great trail sled northern Minnesota and UP of Michigan.
As for the fasteners I am using countersunk head 1/4-20 X 3 SS through all the locations typically found in the stock splitter and lower bumper fascia. Think there is about 20 of them and holds everything from the undertray through the new foam spacer. Added the large countersunk washers from this go-kart place www.kart-master.com
Along with the 4 rods mounted into metal the splitter is pretty sturdy. I think I am going fabricate some brackets at the rear to further support it.

View attachment 64013
Two words....elevator bolts.
 
Not a bad solution at all! Good stuff. Would love to hear your follow up once you get it out or if you have any data to compare to.
AJ,
As an engineer I wish I had more data regarding this combo. When I built this car last year I added the wing and the splitter right from the start so I never tracked it without the aero add-ons. I am strictly going with what I see, what I read, what I can experiment with and what I learn from all that input. Along with personal experience I carefully read and attempt to apply what I learn from forums like this. I certainly appreciate any input or ideas. I do know that last year my Boss was very stable at speed down the mile long straight at BIR and into turn one so this year I will be able to compare at the "feel" part of my experimenting.
 
533
361
sfo
AJH,

in the early porsche 911 days they ran cars with lexan back window and holes in it to let the air out from running windows open. Later it has been said that actually created more drag. The new theory was a sealed car interior with windows open could trap a volume of air and any new air would flow past the full interior making , a counter intuitive, less drag.

Which is the right way to go? Vent the air coming in through the windows or seal the interior limiting airflow from entering the windows so it spills over?

I loved your S550 rearsub frame retrofit thread by the way...
 
AJH,

in the early porsche 911 days they ran cars with lexan back window and holes in it to let the air out from running windows open. Later it has been said that actually created more drag. The new theory was a sealed car interior with windows open could trap a volume of air and any new air would flow past the full interior making , a counter intuitive, less drag.

Which is the right way to go? Vent the air coming in through the windows or seal the interior limiting airflow from entering the windows so it spills over?

I loved your S550 rearsub frame retrofit thread by the way...
With windows down, and holes at the base of the rear windshield, I'm almost positive air will go IN those holes. Like driving an F150, or any trunk with a rear slider window. With front door windows down, open up that rear window slider and air rushes in it. Most clubs and sanctioning bodies dictate windows have to be down, so I would not have any holes in the rear window. About 5 years ago now I was about to attempt a rear mounted radiator and had a big hole cut out in my trunk where the liscense plate goes. I didn't seal it and during a rain race I could physically see the mist during a rain race coming in from that area!
 
AJ,
As an engineer I wish I had more data regarding this combo. When I built this car last year I added the wing and the splitter right from the start so I never tracked it without the aero add-ons. I am strictly going with what I see, what I read, what I can experiment with and what I learn from all that input. Along with personal experience I carefully read and attempt to apply what I learn from forums like this. I certainly appreciate any input or ideas. I do know that last year my Boss was very stable at speed down the mile long straight at BIR and into turn one so this year I will be able to compare at the "feel" part of my experimenting.
Hey, feel will still point you in a direction. I remember going from a flat splitter to a tunneld splitter and the car was so loose in the high speed stuff I had to add a few degrees of wing. Do you have any better info on those countersunk washers? I turned down my own on my mini lathe when I built my floor, but buying something similar would be nice. Their website is terrible tho.
 
5,141
5,663
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
 
Hey, feel will still point you in a direction. I remember going from a flat splitter to a tunneld splitter and the car was so loose in the high speed stuff I had to add a few degrees of wing. Do you have any better info on those countersunk washers? I turned down my own on my mini lathe when I built my floor, but buying something similar would be nice. Their website is terrible tho.
Hey AJ,
It looks like Kart Master has the majority of the washers on eBay. I used the CW33 washer.
 
4,515
5,004
the original Shelby Gt350Rs had their rear windows lowered so the top was open. being around for the "flipper" wings in CanAm, and the Daytona/Superbird/ Talladega stock cars of the late 60s, I love this stuff. I designed a body for a kart at Daytona, I ran around the track with my glove off trying to "feel" where the air was coming in and out of the kart body. It won it's class the next year.

REEG5CZt.jpg

MPbi8ZVt.jpg

vJG9tTSt.jpg

95DIs35t.jpg
 

the original Shelby Gt350Rs had their rear windows lowered so the top was open. being around for the "flipper" wings in CanAm, and the Daytona/Superbird/ Talladega stock cars of the late 60s, I love this stuff. I designed a body for a kart at Daytona, I ran around the track with my glove off trying to "feel" where the air was coming in and out of the kart body. It won it's class the next year.

View attachment 64034

View attachment 64035

View attachment 64036

View attachment 64037
Interesting. I wonder if they were using the low pressure at the top on that original gt350 setup. Coupled with the very gentle slope of the rear glass it may have worked in that situation and location.
 
5,141
5,663
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Interesting. I wonder if they were using the low pressure at the top on that original gt350 setup. Coupled with the very gentle slope of the rear glass it may have worked in that situation and location.
The top of the window was angled down so the air rushing over it would pull from the opening

yhst-13525187779972_2268_67802317.jpg .
 
5,141
5,663
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
4,515
5,004
They also didn't have a big goofy wing so the air over the roof could flow over the back of the car. At best they used a small kamm style rear spoiler.
 
533
361
sfo
Can you pull the 3rd light on s550s and vent the back similarly after the backing plate for 3rd light removed?20210402_111640.jpg
 

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