Just a quick rundown of my Porsche Cayenne Throttlebody install. The TB is ID 78mm as compared to 72mm original and a lot cheaper than F360 (76mm) or F430 TB´s (80mm) that is the usual choice. I bought a second han one of Ebay for 50£.
First of I did not really know what to expect and reports from others are not consistent. But I like tinkering and realized I could do it for little money so went ahead.
I am a mechanical engineer by trade so first was to design a suitable adapter to soften the increase from 72 to 78 and allow for easy installment. I drew it up an had it 3D printet in PA6. I was concerned about air thightness initially but it was no issue. The adapter is 16mm thick.
1. Previous setup. CDA airbox - silicone bend - AFM - silicone bend - TB
2. Cayenne TB - adapter - Silicone bend reduction - clip
3. Closeup adapter
4. Adapter installed with M6x20. Holes for TB threaded M6
5. TB installed with original screws
6. Final install. TB plugged in.
First start was almost normal. Iddle took a little longer to settle in. It came to rest at 700 like normal.
So on to the driving experience. Theres a big difference in throttle response. It comes on much stronger and makes driving fast a lot more effortless. Slow driving is not affected. WOT seems a tad quicker but hard to tell. I dont think you gain any hp but I would certainly do for the driveability. It just feels a lot more eager to move up the rev range.
I have been running the car for a week now and no issues so far.
I am due a RR session soon so might switch setups on there to measure.
If there is interest I could make the adapter open for public printing on Sculpteo. http://www.sculpteo.com/en/s/jacobsen/