STG

I did IPD and BMC as noted here a few months ago. No light, no issues. Only better sound and slight performance increase. Dealer install was like $600.00

AlbertC4S

Thanks for the input. That is exactly was I was thinking of doing along with upgrading to PSE on my C4S.

STG

It will transform your car! You'll be amazed.

PSE + IPD + BMC = pure driving bliss

Your stereo will be used a lot less.

ntravaglino

Back to STG's post with the regular and X51 intakes schematics (#15 in this thread), what is the purpose of the "shaft flap" housed between the two pieces of the upper intake? It looks like it moves/rotates in its seat, and is not just a fixed fin guiding air in some way.

Larry Cable

can you highlight the part(s) on his diagram that you are referring to?

ntravaglino

On the X51 version, parts 10 & 11 - shaft flap left and shaft flap right

Larry Cable

gotcha, that's what I thought you were referring to! I'm TOTALLY guessing but they look a bit like a 'per bank/side' throttle body ... adjusting the amount of airflow into the cylinders...

9914s

I had mine installed at Champion Motor Sports for $1195 (part and labor). Nice upgrade I really enjoy the added induction noise couple with BMC filters. Even my wife agrees that the car feels and sounds better.

ntravaglino

Larry - seems you're right on the X51 intake flaps - used to regulate/restrict airflow to the non-firing cylinder bank. I came across this detailed write-up last night (please excuse the cross-posting from another forum):

http://www.germanboost.com/showthrea...ering-Magazine

STG

Great find

PJA

Reviving this old thread - this would 100% void the CPO warranty on my engine, correct? Or only the intake system?

mdrobc1213

Tricky gray area here my friend which can differ per dealer and per owner and event/issue from what I've heard and seen. My SA said no they would have to show that it damaged something and it was related to the IPD. In their defense he also added they've done quite a few cars with IPD and filters either BMC or K&N and thus didn't see it as a big deal and were experienced and familiar in this mod in the 991. However say in the 981, it causes CELs which are almost impossible to clear without letting the ECU learn after a couple of hundred to thousands of miles. That mod is often done along with a GT3 throttle body upgrade which could be seen as waranty voided or more likely. But with IPD only, no tune (often done together also) my SA said they'd have a hard time denying a repair on an otherwise well kept car that they maintained and knew, and which had nothing else wrong and modded. But I assume the unsaid piece in this would be 1) car and case as presented itself and cost of repair and 2) likely relationship between owner and dealer and 3) whether it was a car they had seen before and worked on often.

Nothing is absolute tho...but it is a worthwhile mod IMHO and I did it when I had my Akra Ti exhaust done. My 2 cents.