Hey Everyone,

Just a quick question...

I have my 991 Turbo in at my Porsche dealership right now being fitted with a Europipe exhaust and IPD Plenum. The head tech there has just rung me and said he is a little concerned with the plenum. Apparently the fuel tank vent line is rather stretched, and he's a little concerned with it.

Now, to clarify, he said he has made it work, but that he is concerned for the long term use of it, and possible failure.

Does anyone have a work around for this, or any advice I can offer him?

Any thoughts would be much appreciated.

Scar

 

there is a clip that holds the line in the back. he might need to look for it. remove it and it should fit fine. No need to stretch it.

 

I fully documented this same issue over here. There is no work around. The 991 IPD plenum is a 997.2 part and was poorly modified for use on the 991. Caveat emptor.

- Patrick

 

After reading all that I'm glad my installer recommended avoiding the IPD plenum.

Saved me a couple grand and I'd be really pissed after reading that thread.

 

I must wonder why anyone here never ask questions why Porsche make many engineering changes to new model engine to get same extra hp when IPD "plenum" is already available for no work at all?? This plenum power "miracle" raise question why Porsche not use it now...and it does not fit new 991tts engine properly either!! I also would demand refund!!!!!...and money for time to have Porsche head tech take it on and off!!!

 

Thank you Pro and Patrick for your input. My tech had already done what you mentioned Pro and unclipped the line. He's happy enough for me to drive away (just not 100%)

Initial feelings... well it's hard to say because I had the Europipe fitted at the same time. My tech's exact words were "it feels much more ballsy". For me, I can definitely feel an improvement in performance. If the GIAC stage 2 improves as much as they say, this car is going to be a rocket.

HRE's on next week and GIAC the week after

Patrick I definitely understand your concerns, and at the first sign of a problem it will come off. Till then, I will at least be interested in Cpais doing the dyno testing with Plenum only. Must say though, why doesn't IPD just manufacture a new plug to go with the plenum which would alleviate this problem... it seems like a relatively simple task.

Scar

 

a new high-flow exhaust has that effect.


impossible to say how much of the change to attribute to the plenum.

 

I would much rather see a comparison of back to back runs in a real world situation. There's a reason that Porsche went from an aluminum plenum in the 997 to the plastic one in the 991. It's called heat soak. That 5lb hunk of aluminum that you just installed - hovering inches above a hot engine - is going to get very hot and in turn heat up the intake air going into the engine. Plastic doesn't transfer heat as well and is a much better material for intake components. Doing a single dyno run and then letting the engine cool for two hours while you install a plenum and then doing another single dyno run won't tell you much about how the product will perform on the street.

-Patrick