Does anybody made a DIY rear undertray/diffuser ?

GriffX

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Hello

The GT350 has a undertray plate from the axle to the bumper and covers the carbon canister backpack. I think it would be a nice aerodynamic optimization for the S197, too.

Cheers


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GT350 with aftermarket strakes:
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Candy10

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I wonder how close in size the GT350 piece is to what would be needed on an S197, maybe could be adapted. But may be easier to find someone talented with ABS molding to have one done. When I was tracking my car, I always wanted to eventually make the entire underside as smooth as possible, using pieces like this. Never reached that point before changing direction on the cars purpose, but if bolt on pieces like this were available itd be a no-brainer
 

GriffX

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I haven't found the dimension of the GT350 part. The needed size is roughly 80x80 cm. The GT350 part is bolted to the bumper on one side and to a bracket to the underbody between the sway bar and the differential.
On our cars we must attach a bracket to the spare tire panel.
I was not able to find any information about the APR part, how long it is, where it is bolted, no instruction, no detailed picture.
These projects are always very down on the to-do list, it takes a lot of time just for the "how to bolt on" part. I spent many hours just to look at my front underbody to get ideas for the front undertray.

Unbenannt.jpg

 

Dino Dino Bambino

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Candy10

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GriffX

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Not worth the money IMO.
Mine's a simple DIY black plastic job that fills the void between the evap system and the rear bumper cover. This substantially reduces the amount of air that stacks up behind the bumper cover and potentially reduces drag, especially at higher road speeds.
Sorry, I'm German, no easy solutions allowed hahahaha..... look at Vanos from BMW :)
 

Dallas281

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C2 aero makes some good rear diffusers that even cover the evap in the rear. APR sells the front one's that extend to the sides of the front bumper. Couple that with the 2010+ extension and louvered trays, should make a difference in cooling, hood flutter and stability on the road
 

GriffX

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C2 aero makes some good rear diffusers that even cover the evap in the rear. APR sells the front one's that extend to the sides of the front bumper. Couple that with the 2010+ extension and louvered trays, should make a difference in cooling, hood flutter and stability on the road
Thanks, that was helpful. I made an almost flat front undertray, it also lowered the wind noise.
 

Dino Dino Bambino

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C2 aero makes some good rear diffusers that even cover the evap in the rear. APR sells the front one's that extend to the sides of the front bumper. Couple that with the 2010+ extension and louvered trays, should make a difference in cooling, hood flutter and stability on the road

In addition to my DIY rear under tray, I've also done several front aero mods resulting in significantly better gas mileage, high speed stability, and NO MORE hood flutter:

 

GriffX

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In addition to my DIY rear under tray, I've also done several front aero mods resulting in significantly better gas mileage, high speed stability, and NO MORE hood flutter:

No mileage compare so far, but I noticed a much smoother ride on the Autobahn with the front undertray.

How do these splitter strut rods work? Are they stable in all directions or do they have a weak point? Are they adjustable in length?
 

GriffX

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My 2010 doesnt have that louvered splash shield. Now I want it
I made one from ABS and lowered the part at the radiator support on my 07. The height difference from front to the k-member is now only one inch. Next time I order some ABS sheets I will probably change the OEM part also to make it flat.

ready.JPG
 

DieHarder

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I made one from ABS and lowered the part at the radiator support on my 07. The height difference from front to the k-member is now only one inch. Next time I order some ABS sheets I will probably change the OEM part also to make it flat.

View attachment 96645

Is that a home lift? Who makes it? What does it cost?
 

GriffX

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Is that a home lift? Who makes it? What does it cost?
It's the ezcarlift.com I bought it when I repaired my differential. All lift have pros and cons. Nice is I can support the engine by putting a 2x4 below it and lower the lift by millimeters. I really like it.
 

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