I just got my car started and the car holds 30# at idle but will not go above 45#or 50# when reving. I am wondering if the spring in the opv is old it is the 3 piece style. I have another one but hate to tear down if i don't have to. the oil pressure will increase then drop then increase and drop again as I rev the motor. It maintains 30# at idle.

The 3 piece valves are more troublesome. It's worth the time/effort to switch to the updated early-style one piece design in any case.

Sterling Doc wrote:


There is a reason Porsche update the design. It is probalby a good place to start. The other place is to make sure the crank bolt is torque to spec. 155ft-lbs I believe.

joepaluch wrote:


I've got my cooler housing off right now and it was suggested by David Dirks to go with the one piece as well. However, at over $400 for the part on Pelican, I'm not really considering it as an affordable switch. Are used/older one-piece OPRV's reliable and not wear out like the 3 piece or is a new 1-piece the only way to go?

I have no concerns about used 1 piece valves. Make sure you get the "replacement" type (fig A below). These are designed to be used as replacement to the 3 piece valve. The ones in later 87 and 88 motors are different and will not match to the block. If you notice the top of both the on in Fig A has an o-ring (typically green) on the end that sort of uncaptured. The one in fig b has proper O-ring groove on it and only for engines that came with 1 piece valves. The O-ring color is most likely black.




Now there is some oddities as well with using a later engine oil filter housing. That is what my notes are referring to on this picture. I have used my 86 951 oil filter housing on both an 84 block with Fig A style OPRV and also on a 88 block using fig B style OPRV. I have never used a 3 piece valve on any of my engines.

Thanks for the info Joe,

I've got an 84 block with a 951 cooler that has the 3-piece. If I could find a used one I'd rather have that than pay 4 bills for such a small part.

Sounds to me like I could run the shorter one without problems...now to find one!

Ryan