Torque Curve, DFI Engine

Ever since the new DFI engine was announced I have been curious about how much stronger that +25 HP would feel and what regrets I would have for not waiting. ('08 CS, August 2008) The latest issue of Panorama has arrived and with it an article on the '09 Cayman (discussed elswere) Included is a power and torque curve. I have taken the values from the Pano article and plotted them on to the torque curve in the owner's manual. What follows is a summary of the comparison. First, understand that the graphic in Pano is small and as a result my numbers are somewhat imprecise. As a general observation, the dip in the torque curve of the pre '09 engine around 3500 RPM is gone. The DFI engine torque is everywhere higher than the previous engine, but most of the difference is above 4000 RPM. The DFI curve peaks at 4500 RPM and starts to fall off from there. What follows is a tabulation of the increase in torque for the DFI engine at the listed RPM: 2000 RPM 8 ft-lb 2500 8 3000 8 3500 14.5 This is a result of the dip in the pre '09 engine. 4000 5 4500 21 5000 19 5500 15 6000 12 6500 20 This is a result of the rapid fall off of the pre '09 eneine If the rule of thumb that a person can only begin to feel power increases when they exceed 10 % is valid, then below 4000 RPM the new engine will feel much like the old. Given the rapid rise in torque from 4000 to 4500 RPM, I would expect that a nice power surge would be noticable, but even here the increase is well below 10% Overall, my guess would be that the new car will feel about like the the old car with the Softronic/plenum/free flow cat back modification that has been much discussed here; worthwhile but not game changing.

For some reason the RPM and torque valuse above have run together. Sorry. The second number after the RPM is the torque value in ft-lb.

Thanks for the careful work on the new engine's torque curve. However, in my opinion, the plenum/flash/catback mod IS game changing. The car is vastly quicker and more entertaining after those mods!

Hello All, I thought that I would post the DFI engines ratings in case some have not seen them. MY2009 MA1.20 Boxster 2.9 188KW 256HP MA1.20 Cayman 2.9 195KW 265HP MA1.21 BoxsterS 3.4 229KW 311HP MA1.21 CaymanS 3.4 236KW 321HP The differances in HP are by tuning as per engines generation. Best Regards, Scott Slauson

Scott, Whats your thougts on upgrading the DFI Engine? Can a similarly modified DFI Engine be have more power than the old model? I think the intake manifold is now different, so the same SRP mod may now be less effective if at all? What do you think? :cheers:

The intake is very much different. The heads, cams and many other parts are even different between the Cayman and the CaymanS . This also applies to the Boxster . Have no worries as I'm already working on upgrades as we speak. The changes should be another 10% on displacement. Now until I finish them nothing is absolute. Best, Scott

If you want to get a flavor for the new DFI motors, go drive a facelift 997.2 (or 997.2S) against a 2008 model. The difference is very obvious. Aside from pulling harder (it can be felt), the DFI motors are much snappier in terms of throttle response and they rev much more freely near the redline (which is higher now). A very worthwhile improvement. Also, they have reportedly fixed the RMS and IMS issues and made it track ready (no oiling issues under high g loads).