Metal brackets are also included...
Metal brackets are also included within the package to mount securely to the NSX's aluminum chassis frame.
Driving ImpressionsAfter installing the under panel aero from Downforce, we tested the new products and spread the NSX's wings with some spirited driving. While taking the car on a testdrive, the NSX was more stable at high speeds and also surprisingly quieter from road noise. This was possibly due to the fact that the air was basically gliding underneath the panels and didn't stumble into any open patches under the car. Some promising test results came when we encountered a sweeping 45-degree freeway interchange. We hit triple-digit speeds before we realized how fast we were going, but then had to slow down due to slower moving traffic. The NSX didn't flinch one bit and remained stable through the turn. We still haven't taken the car to the track to see how it performs, but we have good expectations for the aero mods.
Here's a shot of the rear...
Here's a shot of the rear undercarriage before the diffuser is installed.
|Battery tray ||$350 |
|FRP front bumper under tray ||$350 |
|Carbon-fiber front bumper under tray ||$500 |
|Carbon-fiber fuel tank cover ||$435 |
|Carbon-fiber NSX-R OEM small diffuser ||$450 |
|Fiberglass DF-R diffuser ||$675 |
|Carbon-fiber DF-R diffuser ||$825 |
|NSX-R hood exact replica FRP (MSRP $9,800) ||$1,750 |
|Carbon-fiber hood duct exact NSX-R replica ||$450 |
|Carbon-fiber hood duct exact NSX-R replica DF-R version ||$650 |
|Carbon-fiber rear wing exact NSX-R replica (MSRP $6,800) || $1,390 |
Using the supplied brackets...
Using the supplied brackets included with the diffuser, remove the factory sway bar bracket and mount both steel brackets on either side.
Using an Allen wrench, loosen...
Using an Allen wrench, loosen or tighten the two designated screws to adjust the rear diffuser to offer more or less wind resistance.
The rear diffuser install...
The rear diffuser installed.
Chou says the DFR rear diffuser...
Chou says the DFR rear diffuser design offers better exit flow when compared to the OEM NSX-R diffuser. The DFR design was based on the original NSX-R prototype design that offered longer strakes (fin design). Downforce provides both the NSX-R OEM diffuser and the DF-R versions depending on the owner's preference.
Info for the aerodynamics...
Info for the aerodynamics provided by Honda Co. Ltd Japan:
-The NSX-R carbon hood will result in -0.025 coefficient of lift reduction value. The number is negative because we don't want lift. The hood duct inside the hood will be -0.010.
-The front bumper undercover with the battery tray is -0.040.
-The rear spoiler is -0.085.
-The NSX-R OEM small factory diffuser is -0.002 and also has a Cd of -0.003. This is negative drag meaning the diffuser improves the drag coefficient.
-These lift reduction figures reflects wind tunnel testing with the NSX-R underbody paneling piece by piece.
Factory NSX-R wind tunnel...
Factory NSX-R wind tunnel testing data provided by Honda Co. Ltd Japan:
-Overall Clf (lift coefficient/front): -0.100 reduction value
-Front Clf: -0.040 reduction value
-Rear Clf (lift coefficient/ rear): -0.060 reduction valueCd (coefficient of drag): 0.32
At 112 mph, this data translates to a vertical force of 80 pounds on the front tires and 55 pounds on the rears. When planning to add aero to your NSX, be sure to properly balance the car. For instance, the NSX is balanced at 42 percent in the front and 58 percent in the rear. So ideally you don't want to add downforce only to the rear, because this will throw off the balance of the car-especially high-speed stability.
The Downforce NSX-R replica...
The Downforce NSX-R replica hood was designed as a true carbon-fiber piece, using a double-sided carbon design. A vented hood is a required piece for anyone planning to use the underbody paneling since the opening is used to vacate the air properly.