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Tech Articles – Working on Your Porsche

Ever wonder if it is possible to work on your own Porsche and save 100’s if not 1000’s of dollars with the gratification that you did it yourself? We’ll try to build up this section with “how to” articles from simple oil changes to upgrades and modifications. Got an article of your own? Send it to webmaster@cnypca.org and we’ll publish it!

IPD Plenum Installation on a Cayman 987.1

So you want a little more performance out of your 2006-2008 Cayman? (or Boxster though the procedure is slightly different). The updated intake plenum from Innovative Pro Design might be for you!

The plenum shown in this installation procedure should provide about 15 extra horsepower and 20 lb-ft of torque. This is done by eliminating the restrictions of the stock, divided intake plenum, as well as relocating the throttle body right next to the plenum.

In addition, this plenum helps to straighten the path of the driver’s side shifter cable and simplify the AOS (air oil separator) inlet for those who may want to install a catch can to prevent oil from being introduced into the intact tract. The stock shifter cables are known for failing around the 80k mile mark, but more of that in another post. The air oil separator will also be a separate post.

To acquire an IPD plenum, you can either contact me (webmaster@cnypca.org) or direct to https://ipdplenums.com/products/plenums/caymans/9871-caymans. Note that they also make performance improving intake plenums for other Porsches as well!

Recommended tools required for the installation include:
* 7mm socket and nutdriver handle to remove and replace hose clamps.
* 10mm socket with a universal joint adapter and socket to loosen the nut holding the stock manifold in place
* An E10 socket or nut driver for Throttle Body, oil filler tube bracket and factory plenum hold-down nut.
* Torx 30 screwdriver to remove the engine cover.
* Large Flat head Screwdriver to assist in gently removing the stock intake boots
* Pliers and/or Channel Lock pliers for vacuum lines
* Hose cutter or razor blade to trim the stock vent hose

Procedure:
1. Remove luggage net and carpeted engine cover. This requires the carpet and attached foam to be bent in order to clear the outside tabs. It is recommended to begin the removal process at the front of the cover where the tabs are smaller. Now remove 5 bolts that secure the engine cover with Torx 30 screwdriver.

2. Disconnect crank case vent breather lines from both sides of the factory plenum and where they converge at the oil separator. Remove entire breather line assembly. Note these clamps are“Finger” squeeze type clamps that lock into place at the top and bottom of the clamp. You may need the gentle persuasion of some pliers to squeeze the clamp together. Note that the clamp is squeezed at the hash marks ONLY! They will slip right off when this is done right.

3. Remove 10mm nut that connects factory plenum to support bracket located next to the engine hoist support.

4. Loosen all 4 hose clamps (red arrows) around the rubber boots that connect factory intake plenum to intake manifold utilizing the 7mm socket and nutdriver handle. Make sure to loosen clamps as much as possible without allowing the clamps to come apart. Leave clamps in place.

5. To remove factory plenum slide the rubber boots outward (away from the plenum) onto the intake manifold as far as possible (green arrows). Try to push the boots further onto the manifold towards the outside of the car to help ease factory plenum removal.

6. Loosen hose clamp on ribbed intake hose that attaches throttle body to MAF (Mass Airflow Sensor) with the 7mm socket and nutdriver handle. Utilize a flat bladed screwdriver to gently loosen the boot from the MAF. The MAF is located down and to the left when looking at the engine from the rear.

7. Remove the factory plenum by lifting plenum upward. The plenum will still be attached by two vacuum lines on underside of plenum. First disconnect the vacuum line that attaches to the factory vacuum actuated valve. Disconnect this line by carefully pulling so as to avoid disconnecting vacuum line from opposite end deep inside the engine compartment.

8. Disconnect throttle body from factory plenum by removing all four E10 bolts (red arrows). Then either lay the throttle body to the left side of the motor or disconnect the throttle body wiring harness by squeezing the sides of the connector (green arrows), gently wiggling the connector out and set it aside.

9. Now disconnect the second vacuum line situated on the underside of the plenum. Slide squeeze clamp off nipple with a pair of pliers and slide hose off nipple. This may require the use of Vise-Grips to loosen up the hose before pulling it off.

10. Remove the clamp that attaches the crank case breather corrugated plastic vent line to the engine block so as to provide additional room for the IPD silicone hose (red arrow to the left). NOTE: these vent lines can become very brittle and possibly crack/break when moved around due to years of extreme temps and repeated heat cycles. If the vent line cracks or break the replacement Porsche part number is 987.107.246.01

11. Remove the rubber mount that previously supported the factory plenum, located next to the engine hoist bracket and crank case breather vent line.

12. Remove the two E10 bolts that hold down factory engine hoist bracket (two red arrows to the right). This will provide additional room for routing of crank case vent line. Keep engine hoist bracket stored where you will not forget its location.

13. Remove factory rubber ribbed hose that connected to MAF (Mass Airflow Sensor). All hose clamps will be re-utilized.

14. You are now ready to begin the IPD plenum installation. First, plug vacuum line that previously connected to factory flapper valve if you haven’t already done so. Use small provided plastic line plug. This line is no longer necessary with the IPD plenum.

15. Reinstall the throttle body onto the IPD plenum. Be sure that throttle body is positioned so that the black plastic portion of the TB is situated to the left (driver’s side). Torque the four E10 bolts to 6 ft-lbs. Remember to plug the throttle body harness back in if you removed it!

16. Reconnect vent line with squeeze clamp on IPD Cayman S plenum and slide into place in between manifold hose clamps. Note that the hose will likely need to be trimmed to accommodate the smaller diameter brass nipple on the IPD plenum.

17. Slide rubber boots onto IPD plenum. Be VERY sure that rubber boots are properly seated,aligned and positioned to as to avoid any leaks which could cause Check Engine Lights.

18. Attach hose clamps that connect rubber boot to IPD plenum FIRST, leaving the manifold clamps still loose so as to be able to maneuver plenum up and down for proper orientation.

19. Angle plenum upward so you can visually verify that the rubber boots are properly spaced by looking down inside the IPD plenum.

20. Snug rubber boots that connect to manifold tight enough so you can still adjust the angle of the plenum manually.

21. Place factory hose clamp (previously used to attach original factory ribbed hoses to Mass Airflow Sensor) onto IPD silicone hose and push silicone hose onto MAF sensor housing.

22. Now for the most difficult part of the install. Place other hose clamp loose on throttle body end of silicone hose and gently drop throttle body down to meet the silicone hose. This might require a large pick tool. Bring silicone hose and throttle body together until they are engaged. Once engaged, lower the Plenum and TB until you achieve the optimum fit that should have the throttle body going “straight” into the silicone hose which should enable the hose to be as “open” (less kinked) as possible. Again, with the engine hoist bracket removed and the crank case breather line free to be pushed back below the Plenum and out of the way you should have ample room to drop the Plenum, TB and Silicone Hose into this desired position. I found that pushing the manifold to the driver’s side allowed the entire assembly to be rotated down far enough to prevent contact with the body. BE CAREFUL not to push down too hard because you will likely crack the brittle vent line underneath!

23. With a pair of pliers (and some rubber in the jaws) bend the tab (on the body) that would normally cause interference with the new silicone hose. This will prevent any unwanted slicing and/or rubbing of the hose causing premature failure. This will NOT cause any sealing issues with the engine cover.

24. Double check to make sure that all connection between the silicone hose and rubber boots between plenum and manifold are properly spaced and positioned correctly, once verified tighten all connections.

25. Reinstall breather vent line assembly. Reconnect hose lines to the oil separator and the right-hand side of the IPD plenum. The hose that extends to the driver’s side receives a block off cap which is included with kit. The block off cap should snap into place with enough pressure.

26. Double check to confirm that all hose connections, boots, clamps and bolts are tight and secure

27. Reinstall aluminum engine cover and secure with five Torx 30 bolts.

28. Reinstall rubber backed carpet engine cover by inserting the rear tabs into the body slots first. Then flex the cover piece to fit side and then front tabs until completely secure. Be sure that the luggage D rings are in the up position, so they don’t get caught beneath cover.

It will take approximately 5 to 50 miles for the DME/ECU to recognize and fully adapt to the increased air flow and make the necessary adaptation corrections complete. The DME tends to adapt quicker when driven in a more spirited manor. Enjoy your new IPD plenum!