Do It Yourself Downforce series

Hey guys,

My name is Mike from Professional Awesome Racing. We started a YouTube series to help people build aerodynamic components that make serious downforce for an affordable price. We call the series #DIYDownforce. Check it out and let me know if you have any question or if you have a topic in mind you would like us to address. 

https://www.youtube.com/watch?v=ssPefKJUZhw&t=11s

PS:I wasn't sure where to put this, mods please move this if you feel its in the wrong section. 

Thanks,

Mike

Sub’d! Looks like it’ll be good info for my endeavors this season.

Good stuff, I'll be watching. I've been planning to put homemade underbody aero on my car starting with a diffuser.

AWESOME! lives up to the name. thanks for sharing. off to go buy some plywood haha. 

Subbed, I keep wanting to do some on my miata but its intimidating even going through the big thread on miata turbo. Attaching to the car is a weird thing to figure out

This is great. The only good aero guy on yt (i knew of previous to now), got a realjob and had to stop spilling the sauce. His info was more theoretical however, with precious few actionable bits of info like this is. Thanks for making this!

p.s. you know it works well when it is disallowed by rule even in SCCA DM/EM. (I'm talking about adding small diffusers to the splitter up front)

Robbie said:

p.s. you know it works well when it is disallowed by rule even in SCCA DM/EM. (I'm talking about adding small diffusers to the splitter up front)

So you have me wondering here.  I have built my splitter out of wood (as seen here https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/1981-camaro-c-prepared-build/59501/page31/) and I was intrigued by the diffusers in the video.  Looking at the class rules for C-Prepared, I don't see where this sort of thing is illegal.

The standard OE front spoiler or a non-standard front spoiler/splitter may be used. If a non-standard front spoiler/splitter is used it must comply with the following requirements: It shall not protrude beyond the overall outline of the car as viewed from above or aft of the forward-most part of the front fender opening (cutout), no portion of the spoiler/splitter may extend beyond the widest part of the front bodywork forward of the front wheel openings as viewed from above, and shall not be mounted more than 4.0” (101.6 mm) above the horizontal centerline of the front wheel hubs. The spoiler shall not cover the normal grille opening at the front of the car. An intermediate mounting device may be used on cars whose front bodywork is above the 4.0” (10.2 cm) minimum. Openings are permitted for the purpose of ducting air to the brakes, radiator, and/ or oil cooler(s); equal openings may be placed in the standard lower front panel directly behind openings placed in the spoiler/splitter. The spoiler/splitter may not function as a wing. This allows a vertical airdam/spoiler above a horizontal splitter, but splitter fences or longitudinal vertical members that serve to trap air on top of the splitter by preventing it from flowing around the sides of the car are not allowed.

The diffuser would be behind the air dam, so it's not like air would be flowing over it.  What do you folks think?

^From that excerpt it sounds like little diffusers in the front splitter are allowed as long as they don't cross that line 4" above the front wheel center.

In reply to Gimp :

Interesting! The way I read that there isn't anything preventing you from doing it, (unless it somehow makes it qualify as a wing, which, i guess it might).

In mod rules it specifically says "diffusers are allowed at rear of car only".

In my particular case, I could maybe see the following not allowing it, but I'm not so sure...

17.S. The hood, hatchback, deck lid, and fenders may be lightened or replaced by ones of alternate material provided the shape is similar to the original and does not confuse the identity of the vehicle. Factory bolt-on fenders may be replaced in their entirety. Cars with non-remov- able fenders may replace the front fender panels going forward from the foremost door opening and the rear fender panels going rearward from the rearmost door opening. Closed cars must not remove stan- dard material above the horizontal line placed at the lowest point of the driver’s door window opening, with the exception that OE removable panels (e.g., T-tops, targa tops, sunroofs) may be removed or replaced with panels of alternate material provided that the dimensions of any replacement panel do not vary from those of the original by more than 1.0” (25.4 mm) in any direction. The approval of alternate body panels does not authorize the use of underbody or belly pans forward of the firewall or aft of the front edge of the rear wheel opening. Ground effect tunnels and/or attempts to gain ground effects are also not authorized. Any such elements incorporated in the otherwise approved components must be removed or disabled.

Emphasis mine

Honestly if I could just find out how far my front splitter needs to be and if extending my rear diffuser behind the rear bumper for me would be amazing. 

In reply to ProAweMike :

I'd be interested to see some of your analysis behind how your splitter diffusers produce 2x as much downforce over a "flat" splitter

In reply to Nugi :

Kyle is great but we wanted to bring everyone for practical information. Thanks man. 

In reply to sleepyhead :

We have designed quite a few splitter with integrated diffusers and they greatly improve the effectiveness of the entire package. All are designed with CFD in Fluent, Openfoam, or SW CFD for quick checks. Air damns and flat splitters aren't overly effective, so adding the diffuser does wonders and improves interaction of the whole splitter blade. There are many white papers and engineering articles about these types of designs. I am not inventing the wheel, I am just trying to provide am affordable product that helps others take advantage of these designs. 

Thanks,

In reply to wearymicrobe :

What kind of car are you building and what are you doing with it?

In reply to ProAweMike :

2010 Dodge Viper ACR with ACR-X aero package Full flat bottom and dropped low enough to actually make a boundary layer on the track. ~800hp ~3125lb's in race trim. 

In reply to wearymicrobe :

Awesome. Do you have pictures of the car you could send? Do you run in a specific class? We may be able to get you on the right track. 

Thanks

ProAweMike said:

In reply to wearymicrobe :

Awesome. Do you have pictures of the car you could send? Do you run in a specific class? We may be able to get you on the right track. 

Thanks

Its apart right now but once I have it all slammed back together I will get some drawings of what I need answered. 

Hey just wanted to say I saw the splitter diffusers on speed academy videos!

I'm trying to learn all I can about aero right now.

Robbie said:

Hey just wanted to say I saw the splitter diffusers on speed academy videos!

I'm trying to learn all I can about aero right now.

Awesome man. We are trying to get some good info out there. Hopefully the series helps you. 

I just wanted to subscribe. These are the kind of threads I dig!