Finished under tray, More Aero mods
Sorry for the lack of updates, been finishing up the undertray on my car and added a few more under-car aero mods.
I slightly tweaked the design of my middle under tray. Im going to wedge the outer edges into the OEM side skirt. I’ve also reinforced the Inner portion with aluminum C-channel bars. No more flexing! I also cut out a portion of the rear cross section so that the whole thing sits flush with the exhaust pipe.
Here is the middle tray attached to the car. The front cross bar is attached to underside of the OEM sideskirt with a bout 4” of double sided tape on each side. I made sure the CLEAN the underside of the sideskirt with rubbing alcohol to ensure a nice clean contact area. This makes the tape VERY STURDY. The rear cross bar is attached to the OEM jacking points.
Starting to build the rear undertray, which is tricky due to the dual exhausts. I started by used the aluminum window frame bars, attached to the rear crossbar of the middle tray, the other end of the window bars simply tuck into the rear bumper.
I used aluminum flashing to cover the exhaust pipes.
Now I need to fill the gap around the lower control arm. I simply used existing holes in the LCA and bolted on more coroplast.
Building the Rear Wheel Boat Tails (similar to Gen 2 Prius)
They are attached with aluminum L brackets that I double side taped to the underside of the bumper. Used leftover coroplast and black Plastidip.
I’ll eventually smooth them over and mold with the bumper with a thin layer of fiberglass
I also made an inner wheel skirt similar to Basjoos. Made with aluminum L brackets and double sided taped to the middle under tray
Covering the middle exhaust. I used aluminum flashing, double sided taped to the middle under tray (has not fallen off yet!), and fish scaled.
Covering the gap between the front OEM under tray and my middle under tray. I used existing holes in from the OEM under tray and bolted on coroplast
Im also making a more aerodynamic cover for my outside mirrors out of fiberglass
COAST DOWN TESTS – A B C
Take these results with a grain of salt because I did coast down tests throughout the week while finishing the under tray, I was too lazy to keep taking off and on the under tray. So this is more like an ABC coast down test. I tried to perform the tests when the outside temperature was the same around 55*F
Side mirror delete, upper grill block, lower grill block, middle under tray
37.6 sec average
**added rear under tray, rear wheel boat tails
37.57 sec average
**added middle exhaust cover, inner wheel skirts, front oem to middle tray cover
40.53 sec average!!
Also with these mods, I achieved the best commute home from work with 30.5mpg! The previous best was 28mpg.
Im taking my car into the dealership soon for service and will do another coast down test with all of the mods taken off to see if there is a difference.