The head line didn’t exactly scream it but there it was: A modified Porsche Cayenne Engined Riley wins the 24 Hours of Daytona! Wow! I mean I watched the race on Speed Channel and saw it with my own, digitally enhanced eyes but come on—a Cayenne engine? Yes friends, let there be no mistake. One of the top endurance races in the world was won by a modified SUV motor. To be fair, even Porsche isn’t pushing this accomplishment as much as expected because the motor in question was prepared by Lozano Brother Porting in Texas who have been working on a derivative engine for another Grand Am DP class car (Spirit of Daytona) for the last two years. The key is that a race modified, 4.8L, Cayenne motor won the most prestigious endurance race in America.

Many Porsche purists were aghast when Porsche announced that it would bring to market a performance SUV but the Cayenne broke the mold in its class from a performance standpoint. Like the earlier 928 motor of the late 70’s, the Cayenne M48 motor came in initially at 4.5 liters with dual overhead cams, 4 valves per cylinder and Vario Cam valve timing, all of which were being incorporated into 996 and later into Boxster and Cayman (987) motors.

Other engine features that provided a direct link to Porsche sports car heritage included the five main bearings that were integrated with the Cayenne’s sump casting in a manner pioneered by the 928 engine. Because of the vehicle operating angels the Cayenne was intended to encounter, the design and placement of the sump and oil pickups had to be done carefully to prevent oil starvation. In this separate oil returns from the heads to the sump bypassing the crankcase breather channels were used. A sump baffle and low level sump intake assured adequate oil intake on steep grades. The M48 basic geometry was inspired by the Boxster S cylinder dimensions of 93 x 83 mm while the cylinder bores used the 944 solution of a high silicon alloy of aluminum that was tough enough for the pistons to run directly against the cylinder walls. The valves were inclined at 29.6 degrees, well within the range Porsche had been using for all its road going 4 valve sports car motors.

With this heritage and Porsche’s desire to provide a best in class SUV, it’s little wonder that a motor designed to haul families on and off road could find its way to the podium at Daytona.

(“Excellence Was Expected” was a source for this article)