2006-2008 Porsche RS Spyder

Images copyright Pat Michl and Michael J. Fuller
Text copyright Michael J. Fuller

Sebring 2008The front suspension on the RS Spyder consists of upper and lower A-arms.  The lower A-arm mounted pushrod engages an inboard rocker arm to which the torsion bars (1) are connected to.  The torsion bars are mounted rather low and on the side of the monocoque, resulting in a shallow pushrod angle, for center of gravity considerations.  The primary dampers (2) are situated on the front of the tub with the anti-roll input (4, the actual ARB is inside the monocoque) below and both being actuated from the primary rocker arm input going into the torsion bar with a third damper (3, also attached to the front face of the monocoque) receiving input as well.
Salt Lake City 2006The front (and rear suspension) layouts carry over from the 2006 car.

The Spyder’s carbon monocoque consists of inner and outer carbon skins with varying thickness aluminum honeycomb in between.   Unusually the tub is laminated in left and right halves, being glue bonded together on car centerline.  A central carbon and honeycomb spine runs longitudinally through the cockpit, just offset of the centerline.  Carbon internal bulkheads provide additional structure and driver protection.  The RS’ footbox is raised to provide room for the front downforce generating splitter/diffuser.  The monocoque is manufactured by Carbotech out of Austria.

While we're looking at the front ends of the the 2006 RS Spyder (left) and 2007 RS Spyder (right), notice the carbon scuttle bonded to the top of the 2007 RS Spyder's monocoque.  In 2006 the nose bodywork lifted off as a single piece revealing the top of the monocoque (and the access hatches) as well as the front crash structure (as well as suspension and all the mechanical bits).  For '07 the nose bodywork split line has been redesigned and shifted forward, a scuttle is now bonded/riveted on to the top of the monocoque.  The nose proper settles on top of the crash box and the fenders, with the trailing edge of the nose body work picking up on the leading edge of the scuttle.

Sebring 2006
Sebring 2008
The roll over hoops were redesigned for 2007.  The tighter bend and increased section thickness of the '07 version (right) is evident.  This presumably also required the redesign of the upper monocoque as it appears that the "headrest" has been changed to accommodate the altered included angle between the uprights of the hoop.
Sebring 2008The rear suspension is similar with expected upper and lower A-arms, inboard located torsion bars (1) mounted on a structural carbon housing atop the bellhousing and actuated by a lower A-arm mounted pushrod.  The primary dampers (2) are mounted vertically either side the gearbox, just below the torsion bars, and actuated by a rocker arm feeding off the same pushrod input.  A third damper (3) attaches in between the rockers.  The rear anti-roll bar (4) is mounted to the top of the carbon doghouse and also takes input from the rocker.
November 2007A bespoke racing powerplant, the RS Spyder's diminutive and squat 3.4 liter 90░ V8 looks lost in the Spyder’s engine bay.  A desire to minimize center-of-gravity impact of the V configuration certainly drove the design of such a wide angle.  The intake is located in the air-licked front face of the monocoque on the “passenger” side.  The engine oil tank is placed ahead of the engine and recessed in the back of the monocoque, moving mass forward and improving weight distribution.  The MR6’s stout cam covers, coupled with a lack of any chassis members within the engine bay area, demonstrate the structural utilization of the engine; all chassis loads are put through the powerplant.  It is the singular connector between the rear end of the monocoque and the bellhousing/gearbox; there are no other chassis structures or frames tying the back of the monocoque to the bellhousing unlike on chassis such as the Lola or even the Acura (Courage).  That has a lot to do with the engines available to the customer and those engine's ability to handle torsional loads.   Porsche has only one engine to contend, and that allows them to optimize the chassis to the engine and vice-versa. 
Salt Lake City 2007The RS Spyder teams took to running only one muffler, favoring the side of the car that the sound measuring device would be located on track (SLC 2007 here).
Porsche RS Spyder, Salt Lake City 2008A year on (SLC 2008) and we have mufflers on both left and right exits and the massive "coffee can" (chamber pot anyone?) mufflers are gone replaced by something more reasonable looking.
Salt Lake City 2007The Spyder’s gearbox and bellhousing are cast as one in aluminum but with an interesting structural carbon doghouse that sits atop the bellhousing and serves as the mount for much of the rear suspension.  The Porsche designed GR6 gearbox is longitudinal and with the gear cluster as low as possible, reducing the gearbox’s cross sectional impact on tunnel volume and lowering the car’s center of gravity.  Gear selection is made electropneumatically via paddle shifters located on the steering wheel. 

ęCopyright 2008, Michael J. Fuller