Rather watch than read? Here’s our Youtube for this page.
Maybe you’ve seen our Pin cams page with a pic of the end of the cam.
| If not, check this pic out… |  |
| These are located on the very end of the intake cam you can see here. (right cam) |  |
Yes, I called them piston rings, but they’re not really on your pistons, lol… But they sure look like the the same thing! So, what do these rings do and why are they there?
These rings are seals to hydraulic channels that move the cam actuator that is positioned directly over top of these rings. There are three rings to create two channels. One channel acts to Advance your camshaft, while the other retards it. A balance between these two can position the cam anywhere between its fully retarded and fully advanced position. Well, the later cars do this. Early Boxsters, 996s and 996tts have what we call the light switch effect where they are simply on or off, fully advanced or fully retarded. The next gen of cars got to take full advantage of this tech to have complete control anywhere in between as well.
Why are they there?
The actuators on these cams give an incredible range of drivability, increased torque at low end and extended power band on top. Driving a car with and without them is immediately noticeable. A 993 turbo with gt2/Evo cams, twin-plug, 3.8L and all kinds of goodies still lacks the low end torque of a 996 turbo that has cam control, even though the 996tt has the light switch type, and could be further improved with full cam control.
We have applied gt3 tech to the 996tts for a while, and still can, by using a gt3 ecu on a 996tt we could enable full control of the cams. A similarly built 996tt with factory cams vs. a gt3 based ecu setup that could fully retard the cams on top could make an amazing 100-150hp difference in an otherwise identical configuration. First gen gt3s without cam control had terrible idle and low speed drivability. They were basically a full out race car put on the street. The next gen gt3s with cam control had very nice idle, awesome drivability and insane power up top. Porsche continued this further to controlling not only the intake, but the exhaust cams as well for an even better power under the curve.
So what can go wrong?
997.1 turbo owners can probably tell you stories about the dreaded P0016, P0021 and other codes related to cam control. The 997.1 turbo had an issue with an inner sleeve that slipped and blocked off one of the channels forcing the cam control fully retarded, or just super lazy. Replacing the cam with a new one by Porsche didn’t fix the issue since the new production of cams still had the same issue. Pinning those is the best solution, which we offer here.
996TT owners have a different variety of issues with these rings. The first gen rings were cast or ductile iron vs. the stainless rings on the 997.1TT. And these early rings tended to wear badly. Once worn badly enough they’d lose their seal and compromise the control of your camshafts. It’s rare to do damage to the cams themselves, luckily it tends to just wear out the rings. However, getting to them for replacement takes quite a few hours of labor.
So, there’s good and bad with having piston rings on your camshafts… They’re a huge performance and drivability advantage. But do have some technical issues. Luckily none of those issues tend to be catastrophic failures and simply require some maintenance.
Trevor Morris2024-04-22Todd is the ultimate godfather of Porcshe! His knowledge and informative videos have been invaluable to me as a Porsche enthusiast. I'm incredibly grateful for his expertise and guidance. I had an intermittent problem with my 996tt that has plagued the car for 6 years, no shops were able to figure out the problem. I emailed Todd and he narrowed it down within a couple emails, and sure enough he guided me to the problem and it was a simple fix in the end. Not to mention Todd's tuning skills are off the charts, as the car also traps 144mph in the 1/4 mile. Keep up the fantastic work, Todd!
Chris Roundtree2024-02-19I wanted to thank Todd at Protomotive Motorsports for going above and beyond when he helped me sort out a problem with a product that I had purchased from another vendor. Todd seems to always have the knowledge to put together the best combination of parts to make any model Porsche not only go fast or handle better, but do it reliably. He always answers the phone. In the rare event he doesn’t pick up he gets back to you within twenty four hours. Emails get responded to just as quick. I really appreciate having some like Todd available when working on any Porsche as you know he has a proven setup to satisfy any goal. Thx Chris
Antreas Smilas2024-01-22Super in every way..2 years now in ecu and tcu perfect power delivery ,reliable,and fast as mr Todd promise in number...i can say even i draggy was the same numbers as promise to achieve with this set up.
Taylor Berg-Kirkpatrick2024-01-04Todd has got to be the world's expert in forced induction Mezger Porsche engines. I've worked with a bunch of mechanics, tuners, engine builders across multiple Porsches over multiple decades... and Todd has been the most helpful and knowledgeable of the bunch. And this has even been true while working with him remotely! (I'm in CA and he's in AR.) Just by looking at my logs and hearing about my engine rebuild, he's been able to diagnose stuff that in-person mechanics have not been able to. For example, Todd was the only person looking at my car to suggest a problem with a BRV could explain some of the weird behavior... following his advice, I dug in myself... lo and behold, torn BRV diaphragm on bank 1! Wow! Further, Todd has the most experience tuning these cars of any tuner I've worked with. Tune is absolutely solid and safe. Very very confident in his work!!! Absolute strongest possible recommendation!!
N K2024-01-04Todd and his team are true professionals and they always provide excellent customer service, quality parts they sell and very reliable engine builds. This is very rare in our industry today. Great job Protomotive!
raphael wirth2023-05-29Todd est l homme de la situation…. Des difficultés ou des problèmes pour régler le problème? Todd trouve la solution malgré la distance ( je suis français) Merci à lui et son équipe pour leurs conseils … Maintenant mon 997 turbo fonctionne à merveille et est un véritable avion de chasse! Je recommande a 1000% !!! À bientôt pour d autres évolutions !!!
Adam McGregor2023-04-05I don’t think there is a better shop to shop entrust your Porsche to then Protomotive and the Knighton’s. Just search there name with 993 and you can start to get an idea of their storied history of building monster but reliable 911 Turbos! I have over 12 years and 30k miles (street, autox & track) on the Protomotive set up on my 997tt and it has never skipped a beat!
Piotr L. Pawlak2023-04-05Unfortunately they could not resolve my issue, but Todd tried very hard to find some other resolutions. He was very helpful and responsive.
B W2023-03-23Todd is by far the most professional and knowledgeable Porsche person I have ever worked with in my life and I have had many cars and have been doing this for over 20 years. He not only knows how to overcome every single problem, but also knows how to explain exactly what he is doing and brings the car to a point where it feels like stock even though it has double or triple the power. If you go anywhere else you would be making a mistake
Alex May2023-02-20The engineers at Protomotive are absolutely the best. They performed extensive work on my Porsche GT2 and I literally could not be happier. Their work, attention to detail, problem solving and communication with me were all next level. Customer service is remarkable. I had a question while at the track, on a Saturday, and Todd immediately responded to my questions. Class act.
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