Project 981 Cayman - IPD Plenum (Episode 7)
Project 981 Cayman - Build Series
On this week's episode we install the IPD Competition Plenum and GT3 Throttle Body.
The install is pretty straight forward. Here is a great step-by-step guide. Make sure before you put the IPD Plenum on to swap the factory AC bracket bolt with the bolt IPD provides. It's a small difference in height but it allows the plenum to sit where it needs to before putting the clamps on.
Reference the video to learn more about the clamps that hold the plenum to the intake manifolds. It is important to get these lined up perfectly and get the clamps seated correctly. You will need to apply a great deal of pressure to the clamps. We recommend having help from a friend and using a large wrench to pry up the bottom of the clamp as your friend puts weight down on the top side. Quickly secure the bolt and you should be good to go.
Additionally, verify that the clamps on the silicone Y-pipe are properly aligned towards the outer edge to ensure a sealed connection.
After driving for a week with the plenum it certainly makes the car feel more aggressive and lively. The throttle response seems to be improved and at higher RPMs coming out of corners, the power down feels more inspired. The noise is amazing paired with the aFe high flow filters. You will be searching for nice days to put your windows down to hear the intakes suck in the air. We are happy with the feel it has provided and are looking forward to tuning after we get our headers and cat-back on to extract more power from the Cayman!
This graph compares the Cobb OTS Stage 1 Map 30-80MPH pull from second gear before and after the IPD Plenum was installed. The car didn't drop a lot of (about .1 sec and 10 ft shorter distance) but we note that the gear change from 2nd to 3rd gear happened slightly sooner right before 80mph. We will work to find an acceleration speed that is more representative of before/after. We will note, you see a modest increase in acceleration during the mid range from 30-50mph.