2007-2011 Acura/HPD ARX-01a, b, c, d, & g

Images copyright Acura, Pat Michl, and 
Michael J. Fuller

Text copyright Michael J. Fuller
Courage Acura LC75The Courage LC75's rear end.
Courage Acura LC75

Acura ARX-01a
While seemingly identical to the Courage LC75 (left), much was changed on the Acura ARX-01a's rear end (bottom).  The primary difference was that the bodywork on the -01a was shortened by 150 mm, but the rear wing stayed in the original Courage position.  The primary identifying feature of this change is the much shortened legality cheese wedge on the Acura as compared to the Courage.  Naturally the mounting tab for the endplate stabilizer strut has been shifted forward on the ARX-01 to accommodate the shortened cheese wedge.
Acura ARX-01a, Sebring 2007The original ARX-01a's rear end at the car's Sebring debut.  Note the exhausts exiting out above the top of the diffuser trailing edge.  The openings just behind each rear wheel are larger than on the Courage LC75 given the trim line for the trailing edge of the bodyworks is 150 mm forward and thus through a larger cross section of fender trailing edge at that point; Wirth Research didn't alter the shape of the Courage LC75's rear fenders but simply trimmed the bodywork forward.
Acura ARX-01a, Sebring 2007On the -01a the engine cover sweeps up at the trailing edge, effectively forming a spoiler.  This element was detachable and could be changed to suit car setup.  The bulges in the center cover the suspension linkage to the anti-roll bar.
Acura ARX-01a, Petit Le Mans 2007By Petit 2007 the exhaust exit on the -01a had changed from exiting at the trailing edge of the diffuser to now exiting over the top of the rear bodywork.  This detail carried over on the -01b.
Acura ARX-01b, Sebring 2008With the introduction of the AX-01b in 2008, a number of details were changed throughout the car and on the rear end.  The bulge covering the suspension anti-roll bar has obviously been redesigned.  On the -01b the rear trailing edge was now a removalable section (note the parting line and latches).  This allowed different trailing edge shapes, in combination with endplates and rear fender shapes, to be tried as setup required.
Acura ARX-01b, Sebring 2008There were at least two different options available for the rear fender trailing edge shape.  This "trumpet" rear fender trailing edge shape (Sebring 2008)...
Acura ARX-01b, Petit Le Mans 2008...And the original "plain" shape (Petit '08).
Acura ARX-01b, Petit Le Mans 2008Different engine cover trailing edge options, in combination with the rear fender options, were available as well.  The option shown here peaks at the rear wing pylon.
Acura ARX-01b, Petit Le Mans 2008Here's the same option but with a large variable height trailing edge gurney.
Acura ARX-01b, Petit Le Mans 2008The "standard" tail and constant height engine cover trailing edge.
Acura ARX-01c, Paul Ricard 2010The ARX-01c's rear fender trailing edge bodywork is similar to the original Courage LC75 and extends back further than the -a or -b's rear bodywork, terminating in line with the rear wing.  Note also that the rear legality structure is different with a convex leading edge ramp as compared back to the -01b.  The rear brake intake has moved from the lower position up to on top of the side pod ahead of the rear fender leading edge as similar to the ARX-02a.

ęCopyright 2010, Michael J. Fuller