The great 9A1 tuning debacle

Enthusiasts sighed in dismay as the 997.2 Turbo became the first car outside the Boxster / Carrera to move to the new “integrated dry sump” engine, coded the 9A1. The 9A1 motor is an evolution of the M96 which first appeared on the Boxster in ’98 and on the all-new water-cooled 911 in ’99. While the M96 has been plagued with scary reliability issues, particularly relating to the Intermediate Shaft Failure which can completely destroy the engine and the less-scary, but nonetheless annoying rear-main-seal leaking, the 9A1 seems to be trouble-free thus far, is leaps and bounds ahead of the M96, and has addressed the shortcomings of the earlier engine. We can come to the conclusion that if Porsche found it suitable for use in the 911 Turbo at 3.8L of displacement, there shouldn’t be much to worry about at stock power levels.

But the tuning world is not satisfied with stock power levels and herein comes the big mystery of tuning the 9A1. Currently 9A1 tuning is in its infancy compared to the Mezger engine, which went largely unchanged since the 1994 Turbo 3.6, thus allowing tuners to really develop the power and reliability. In the United States, Champion Motorsports and Evolution Motorsports both appear to be making waves with the 9A1, with over 600bhp figures published and impressive increases in 60-130 times noted. The European tuners, probably due to the additional pounding the engines have to take, seem to be a little more coy in publishing figures or making a splash in the tuning community with big hp claims.

Which brings us to RUF. The RT-35, which has an engine based on the 9A1 architecture, puts out a reported 630bhp at 6,500 rpm. RT-35 001, which we have featured in the registry, is a 2WD model with the PDK transmission. US tuners seem to have run into issues with the PDK at higher hp levels and we can only assume that RUF and other european tuners are running into similar issues as well. This 9A1 / PDK combo has the potential to be “double trouble”, because it’s not simply a matter of changing the clutch or transmission output shaft and being good to go for XXX hp. The video below is a prime example of why I am personally skeptical of the tuning potential of the PDK. If you notice, the PDK is in auto mode and is shifting at 6,500 rpm. It’s no coincidence that this is the same engine speed as when the peak power is achieved, and maybe this is the “fastest” configuration, but it still it makes me wonder if maybe the high-revs and strong torque figures tax the PDK a little bit beyond what it’s capable of currently.

I have no doubt that RUF will find a way to wring more power out of the 9A1 / PDK combination and in fact, a yellow 997.2 Turbo has been spotted in the parking lot at Pfaffenhausen with a RUF sticker on the lower section of the door, which leads me to believe development on this new engine is continuing. We will have to wait and see how far the 9A1 can be pushed (either with or without the PDK) and if it will ever replace the Mezger engine as the powerplant of choice for reliable high-hp propulsion.

RT-35 9A1 engine photo from article.