What would be much more useful...
 

Would be to understand the oil flow and pressure readings.

It has to be a case of marginal flow. The question is why?

All swapping does is say that the flow is marginal.

A worn motor will have low pressure and require a large flow to maintain even marginal pressure.

A worn oil pump or blocked passages will lower flow (high source impedance as noted above).

Not much to inspect on DOF - issues would be in how installed.

Grant

Grant, this is going to bounce back and forth probably forever, but let's look at what we know:

1. The car had a DOF installed and developed problems that multiple shops seem to have had a hard time tracking down.
2. The OP was apparently the first person to think of disconnecting the DOF, and when he did, the problems stopped
3. The OP installed a different manufacture oil feed IMS setup that sourced its oil from a different place in the engine.
4. Problems do not reoccur.

Whether anyone likes it or not, in the case of this particular vehicle, an issue resulted from pulling oil pressure out of the cylinder head. Not taking the oil from that source appears to have ended the problem, and drawing oil from elsewhere does not cause the same issues. Perhaps the car has lower than normal oil pressure, but it is not coding or showing other signs of that problem's existence. Implying that the OP should be taking the engine apart to R&D the where's and why for's is a bit much. The OP solved his customer's problems and sent him on his way; that is what shops do, they are not out here to resolve aftermarket product issues for the manufacturer.

These engines are known for having marginal oil flow in the valve train galleys. Noise from the valve train, VarioCam problems, and premature lifter or cam wear are common documented problems that have never been traced to low oil pressure or volume flow from the OEM oil pump to my knowledge. And if you have ever seen the lifters out of one of these engines, many of the system oil passages are rather tiny to begin with compared to other engines. So there could have been multiple sources for what happened; varnish build up in the galleys, a small blockage by some stray factory sealant in the lifters, or God knows what. But the fact remains that disconnecting the DOF stopped the problem the customer was having. That does not imply the DOF is either the root or total cause of the problem; but it does imply it in some manner contributed to the issue.

So rather than becoming defensive, why don't we try and learn from the example and see if it reoccurs elsewhere. It could just be an isolated situation, but that does not mean that it did not happen.

That's pretty much correct
 

Hello John,

Good to hear from you and see you are still participating in some forums.

I pretty much agree with that analysis. But to me, the thing we need to learn, is what amount of parasitic drain these motors CAN sustain, and where the best places to tap it are.

I re-iterate - the symptoms are gone, but i suspect the underlying problem persists.

I also realize that the tech won't take it apart gratis, nor should he. But that's the only data that allows us to, "learn from the example". Otherwise all we do is collect a data point. Noting the occurrence - good. Assuming its not connected to underlying flow issues (maybe indicated with pressure, maybe not) - misleading.

I'd personally like to think about better places to gain oil access - if this ever re-occurs. I'd also like folks to think about flow rates and pressures - not just DOFs and associated losses.

G

The IMS Solution also will utilize oil pressure from the engine to operate. To the OP, when you installed the IMS Solution, did you have any cam deviations recur?

There's a reason why I developed the IMS Solution to use oil from the Oil Filter location, and there's a reason why that's covered under the patent.

For over a solid year I carried out studies on this particular aspect of engine operation. The deviations in OP with these engines can vary by 12-18 PSI based on where the readings are taken from. This is the reason why there's two banks of variable valve timing components.

Amondc...who made the bearing that you removed?
 

Was it Porsche's original?

Was the seal removed?

No the cam deviation problem went away as did the lifter noise.

The offer to Jake was tongue and cheek, I think he got the humor. Its the customers part so he can do what he wants with it.

Grant: I replied on the other board.....

It was a GM alternator bearing. :) :) the seals were still intact.

IIUC the DOF can be purchased with an optional replacement bearing, either ceramic or metal ball bearings, but the source was not advertised. I thought you were supposed to pull the rear seal when installing the DOF? Doesn't an intact rear seal defeat part of the purpose?

Because alternators never go bad.......

That means it was installed improperly
 

The seals have to be removed for the oil stream to work.

That should have no impact on the problem described in the first place, but indicates one error on the original installer's part.

G