Underbody Panels

[CJK]

Hey Folks, just wondering if anyone has any thoughts or experience with underbody panels for the Coupe. Is it a good idea? Has anyone installed such a thing? If so, did you fabricate them or is there someone who makes them? Any input would be much appreciated. Thx.

[edwardb]

Can you explain further? Do you mean added panels that would go onto the frame and make the bottom completely smooth? If that's what you mean, would only seem possible between the front and rear axles. Not over the rear suspension, gas tank, engine, and front suspension. Not aware of such a thing or seen anyone do it. The bottom of the Gen 3 Coupe is already pretty flat and not sure what the advantage would be. This is mine on the lift:

https://hosting.photobucket.com/images/ab234/edwardb123/IMG_1978.jpg?width=960&height=720&fit=bounds (https://hosting.photobucket.com/images/ab234/edwardb123/IMG_1978.jpg?width=960&height=720&fit=bounds)

[lance corsi]

I think the bottom planar surface is nearly as important as the upper body. It can smooth out the airflow under the car and possibly help with fuel economy and possibly top end speed. My 818 is billiard table smooth from front to rear except for the diffuser area. Now, I’m about to build a tow hitch which will interrupt airflow somewhat but I need to tow a small trailer for taking my essentials on long trips since there is very little storage capacity within the interior. I’ll make it removable for when I’m not traveling. Anything is possible if you really want it.

[CJK]

Thank-you for your feedback. I appreciate your thoughts on this.

[Dave Tabor]

I used a cut sheet of HPDE plastic sheet to cover the entire underside of my Coupe from the front below the radiator to just before the rear toe link mounts- this was done as a mock-up before sheeting with aluminum (easy to cut plastic).

My intent was to clean up the undercar (not flat) and perhaps by using some rake, get some negative pressure under the car. Then add a rear diffuser.

Unfortunately, oil temps went up markedly just driving down the highway- my oil cooler is in the radiator exit and is not affected by the undercar sheeting- but clearly there is significant cooling by having the bottom of the engine bay open. I was going to add some NACA ducts and try again but I had a track event so I had to remove the plastic. You may consider vents or just leave the area under the engine open.

I decided to re-visit this and tackle the rear first- that area around the fuel tank is a big parachute- at high speeds air pushes the rear fender-well panels forward - blows them forward out of the arches.

Please post what you do/progress.

Dave
Gen III Coupe #17
19,000+ miles
FRPP 302, TKO600/IRS

[CJK]

Hi Dave, thx for the detailed feedback. It gives me a lot to think about.