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Archetype Racing Corsair Rear Diffuser

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EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Truly an aero component that has been long overdue for the GT350. I present to you the Corsair Rear Diffuser. This will be the final piece of what has been dubbed the "Aero Infinity Gauntlet" by my friend Adam. The other parts being the Archetype Racing Aggressor Front Splitter, Strato Front Splitter Extension, Flanker Side Splitters, and Helldiver Rear Spats (I really need to get all of these up on the site. Message me if you'd like any info on those components or if you just want to go all in on the Infinity Gauntlet). We've moved to a conceptual design with this project. There is still 50+ hours of CAD work and probably double that in CFD before a working piece is laid up into its mold.

I threw a quick blurb together about this project in the Verus Diffuser thread. I'll C/P it below to get everyone up to speed.

The ideal design for an actual motorsport rear diffuser for S550 GT350 would be:

1) Removal of the OEM rear close out panel- Ford Part No: FR3Z-6P013-D (Throw it in a dumpster)
2) Two to four additional support points will need to be added to the under body of the car to support the new diffuser. We all already know that the OEM rear bumper cover clips will not support the OEM close out panel and rear exhaust valance.
3) Full length smooth panel from the differential to rear exhaust valance. This will also incorporate a ~16" long X ~5" gradually sloping expansion chamber X full width of the rear exhaust valance.
4) Minimum of four full length strakes. Possibly two more center positioned strakes that project forward of the rear differential to aid in airflow management.
5) Outboard strakes will come close to the ground. (wear item that can be removed and replaced, as needed) Gradually angling from center to the outboard portion of rear valance. The primary purpose of these strakes is to mitigate tire squirt and high pressure air from entering the expansion chamber. This will also increase the low pressure area that will develop between the two most outboard strakes.
6) Two parallel longitudinal strakes, approximately 40" in length, from the diff to valance will be employed to control and stabilize the low pressure air as it enters the expansion chamber.
7) An appropriately sized NACA duct (CFD) will be positioned forward of the rear differential heat exchanger. This duct will perform two functions. A) Provide the heat exchanger with cooling ram air. B) Create a venturi that draws additional air from the low pressure portion of the underneath between the longitudinal stabilizing strakes. This will increase the pressure differential between the low pressure vehicle under body and high pressure expansion chamber, literally sucking the rear of the car to the pavement.
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That takes us to today. 1/2/2020. Below are the SolidWorks conceptual files for the rear diffuser. At this stage, they are still devoid of details like: mount point locations, NACA ducting, strake size, and overall dimensions. I assure you, all of this will be addressed in the final design.

This will not be a flat 2 dimension plate with parallel strakes. The strakes will be full length and project to the road surface as close as your front splitter. The strakes will be replaceable. I am debating on shipping the diffuser with street and track strakes. I know a lot of guys will want to run this on the street, counting myself as one of them, and replacing strakes due to street wear is not something I'm fond of.

The diffuser will be a combination of carbon fiber and carbon composite. Composite is nearly as light as carbon fiber but will not shatter on impact like carbon fiber, due to the lack of resin needed for it to hold its form. It's heat and pressure molded to be as strong as alloy. If you're familiar with an FP350S front splitter, this would be the same material, and you would also be familiar with its durability on track.

Like everything else I design and sell, it's not built for margin or to meet a predetermined price point. It's built to do the job and the price to do that is the price. There would be an add with a full compliment of composite 'street' strakes, if that option box is checked at check out. This would also include new machined aluminum mount brackets, black stainless hardware, and free freight in the continental US. I'd also work with any Canadian GT350's to get one in their hands. I've already shipped splitters to Canada and honestly, the add in shipping is not that bad. I've already taken deposits for the first three. Two, I know are TMO members. If you have any questions, feel free to ask. DM me if you're interested in the prospective price range.
 

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EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Any idea how far off you are from prototypes being mounted? Apologies, I don't hang out on the other Mustang sites where this info or a link might be posted.

This diffuser is top priority. We're just now getting into an estimated 110 hours of CAD time and plug and mold creation after that. We're looking at a 45 to 60 day window.
 

EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Great question - how will the performance gains be measured?

So here's the bitter truth about performance gains with aero. This applies to any company and basically any part. There are far too many variables to say you will be guaranteed to see, feel, notice "X" amount of performance gain. My approach with aero is holistic. Although each component, on its own, will provide performance gain, it's nothing compared to what is possible with all of the components on the car. Thus the moniker of the Aero Infinity Gauntlet.

When the Corsair Rear Diffuser data is released, it will need to be assumed its in conjunction with a large splitter, splitter extension, side splitters, and spats. That's optimizing the design. It's really up to you, as the consumer, to say when you're done. I'm not aware of any other person or company that is willing to be as transparent and go all in with a fully functional aero offering for the GT350 and offer those parts à la carte or as a cohesive unit.

When this diffuser is released for sale, there is not going to be much, if any, meat on the bone, so to speak, for other companies to improve upon the design without a larger expenditure of money for a very slight performance gain. In the bell curve spectrum of cost for performance, X axis being performance and Y axis being cost, this diffuser will comfortable sit at the apex of that curve. I'm not a guy with a near unlimited F1 race team budget, as I assume a lot of you are the same. So chasing that extra performance at the far right of the X axis doesn't make sense.

And at the end of the day, that's really the product that I would want to build and like minded people will want to purchase. That leans on the ethos of the company name. Archetype. The example of...
 
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Will this work on a 2018+ or only GT350?

Also, where are the exhaust tips going? Are the tips stains in their original place?
 

EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Will this work on a 2018+ or only GT350?

Also, where are the exhaust tips going? Are the tips stains in their original place?

Designed to work with all S550's and OEM exhaust locations will not need to be modified.
 

EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Just a quick update on the status of the CORSAIR S550 Rear Diffuser. We finished off a secondary set of 3D scans for the diffuser pan mold. It appears we'll be able to be 100% bolt in for this solution (at least on the GT350). I do believe that the OEM forward mounts (metal) will cross over to other S550 cars, since they share essentially the same body. The OEM rear mounts (junk plastic) were scanned and will be remade in billet aluminum. You will remove the junk OEM plastic brackets (LH/RH) and bolt in the new AR billet brackets. OEM part numbers are: FR3Z-17D942-F RH and FR3Z-17D943-G LH, if you were wondering. You may want to take a look at yours. They may already be broken. Both were found broke on the 2017 R that was scanned. This may also be contributing to bumper sag, since these two brackets primarily hold up the rear valance/close out panel which are directly attached to the rear bumper cover.

If anyone is aware of any Class Rules for rear diffuser size, let me know. My plan is to have the rear diffuser start forward of the rear differential in that void where the exhaust pipes separate. I know for a class in Global Time Attack, you can't have a rear diffuser forward of your rear axle line. So I'll make that component modular (removable) or not go forward of the axle line at all.

With everything going on in the world, I'm honestly shooting for late June/Independence Day for availability. I have several per-orders already, so I probably wont see a part for my personal car until August. This will be 100% made in the USA, from the pan to the strakes to the billet brackets. I know there's another diffuser (if you can really call it that) on the market. These two parts will not be in the same league.

 
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EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Does this replace the OEM diffuser or will this attach to the OEM diffuser?
Tay, this is a 1,000% replacement and upgrade. I'm almost complete with the final rendering. I've already shared it with the individuals that have placed a deposit for the rear diffuser and they are speechless. It's that damn good. This is a GT350/500 specific part. No cutting, or modifications needed. It will bolt directly to the car, using new billet aluminum mounts, where needed, and possibly two more additional hard points that will bolt in, for added support.

The strakes will be replaceable. It will be available with two strake lengths; track and street. The diffuser itself will be carbon fiber. The strakes will be carbon composite. The same material I use for the splitters. Just thinner. Stay tuned!
 
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Tay, this is a 1,000% replacement and upgrade. I'm almost complete with the final rendering. I've already shared it with the individuals that have placed a deposit for the rear diffuser and they are speechless. It's that damn good. This is a Gt35-/500 specific part. No cutting, or modifications needed. It will bolt directly to the car, using new billet aluminum mounts, where needed, and possibly two more additional hard points that will bolt in, for added support.

The strakes will be replaceable. It will be available with two strake lengths; track and street. The diffuser it'self will be carbon fiber. The strakes will be carbon composite. The same material I use for the splitters. Just a thinner. Stay tuned!

Thats great to hear. I hate diffusers that attach on top of the original diffuser. I am so glad its an actual replacement.

I also love the idea of the replaceable strakes. I have this on my Viper ACR-E. Makes you not have to worry about whacking them.
 

EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
Will this work on a 2018+ or only GT350?

Also, where are the exhaust tips going? Are the tips stains in their original place?
It 'should' fit the entire S550 line. If the GT350's rear close out panel bolts up to the GT, GTPP, etc., you'd be golden. It is optimized for the GT350 and GT500, though.
 
When are we going to see pictures mounted on the car? And pricing.
Do you have to remove the rear bumper and valance to install this?
i love the way my Track Brawler looks on my car. Thank You for the great looking product.
 
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EIGHTLUG

https://www.archetyperacing.com
Supporting Vendor
When are we going to see pictures mounted on the car? And pricing.
Do you have to remove the rear bumper and valance to install this?
i love the way my Track Brawler looks on my car. Thank You for the great looking product.
Official pricing will be released soon for the CORSAIR Rear Diffuser. Plug, mold, and layup costs are being put together now.

The answers to your other question is: - No. You will not remove the rear valance. Just remove the OEM close out panel under your car and bolt up the rear diffuser. It will come with new billet aluminum mounts to replace the OEM plastic mounts.
 
28
13
Tay, this is a 1,000% replacement and upgrade. I'm almost complete with the final rendering. I've already shared it with the individuals that have placed a deposit for the rear diffuser and they are speechless. It's that damn good. This is a GT350/500 specific part. No cutting, or modifications needed. It will bolt directly to the car, using new billet aluminum mounts, where needed, and possibly two more additional hard points that will bolt in, for added support.

The strakes will be replaceable. It will be available with two strake lengths; track and street. The diffuser itself will be carbon fiber. The strakes will be carbon composite. The same material I use for the splitters. Just thinner. Stay tuned!

Official pricing will be released soon for the CORSAIR Rear Diffuser. Plug, mold, and layup costs are being put together now.

The answers to your other question is: - No. You will not remove the rear valance. Just remove the OEM close out panel under your car and bolt up the rear diffuser. It will come with new billet aluminum mounts to replace the OEM plastic mounts.

OK I know I should wait until after I see pictures, but I just want to get some clarity because when I was referring to diffuser, I was referring to the lower black plastic portion that houses the reverse light and exhaust tips. It sounds like you might be referring to it as the valance.

So your piece will not be replacing the valance (diffuser), but attaching to the bottom of it? It will only be replacing the close out panel?
 

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