Cam Oil Restrictors

rw7810 · rw7810's Garage

I know this has been discussed before, but without concensus. I used the new restrictors in my recent rebuild. Still in the break-in phase, about 500 miles. I see pressures between 1.5 - up to 6 & 7 bar. It is a leak free engine, knock on wood, so far. Is this bad? Should I leave it alone and trust the updated oil pressure relief pistons will do their job? Or do I drill the restrictors out?

kstylianos · 04-22-2005, 12:12 PM

I've been running pressures similar to yours for 10K miles on rebuild (also have the restrictors). It's been leak free since. The car has been tracked more than street driven. YMMV

Eagledriver · 04-23-2005, 08:11 PM

I'm in the other camp. I felt those pressures were too high. I worry that the excess pressure will cause wear on the aluminum intermediate shaft gear as well as rob horsepower. My aluminum gear was worn bad enough to need to be replaced when I rebuilt my motor. It had about 90k miles on it and no restrictors. My view is that there is no good reason to use these on an engine that is not worn out. On a worn engine it may help with the oil pressure.

This is just my opinion of course and like Charlie says YMMV.

-Andy

CharlesJones · 04-26-2005, 09:04 AM

I'm not too sure whether to use the restrictors either. I'm in the middle of a top-end rebuild and bought the restrictors based on the recommendation in Wayne's book, but since my oil pressure was fine before the rebuild (a missed shift necessitated the rebuild) I'm not so sure whether to use them.

I've searched this forum and found a link to this article:

http://www.dietersmotorsports.com/tech/2002/3-2002.htm

which recommends the restrictors too, but I'm still not sure if it would cause too high an oil pressure. I'd really appreciate any more of your thoughts and opinions on this subject.

Carrera3.5L · Carrera3.5L's Garage

I didn't have any oil pressure problems with the 3.2L, but changed the restrictors over anyway when building the new 3.5L.

Didn't have any significant wear on the int. shaft gear or sprockets with 88K on the motor without the restrictors.

With the new restrictors, the oil press (according to the gauge mind you) is just under 5 bar while driving at an rpm under 4,000 when cold. At idle, the oil press is at 2 bar when cold.

When the motor is warm and at operating temp, the oil press is between 1.5-2 bar on the gauge at idle. Under acceleration when the motor is warm, oil press is just like when it is cold, just under the 5 bar mark.

Just another data point to throw into the mix.

Ralph