Oil restrictor?

[TurboFource]

I just read a rebuild article for a Twin Cam engine and they mentioned putting
a 1/8” restrictor plug at the left front of the block to keep from flooding the
head with oil and this would increase engine longevity……anyone done this?
Thoughts on it?

[BDA]

I don’t know the answer to your question - I have heard of restrictors being used in other engines. I would recommend your getting a copy of “Lotus Twin Cam Engine by Miles Wilkins. It’s available from Amazon.

[jbcollier]

Engines that run high rpms consistently can benefit from restricting oil flow to the head.  At steady high rpm more oil may be directed to the head than is necessary or desirable.  Over-oiling can lead to considerable oil loss through the breather.  This is for racing engines only.  It is not for a street engine.  The benefit for sustained high rpm will be a liability in normal street use.

[BDA]

The restrictors I mentioned were for a Ford 351 Cleveland race motor. The reason for the restrictors is that the cam was oiled first and it would starve the rods of oil (obviously in a racing situation). It sounds a lot like what you're talking about, JB.

[Pfreen]

I put one in my tc.  No problems and no oil leaks.

[TurboFource]

Pfreen,
What size did you install?

[cazman]

I don’t know the answer to your question - I have heard of restrictors being used in other engines. I would recommend your getting a copy of “Lotus Twin Cam Engine by Miles Wilkins. It’s available from Amazon.

Sorry to hijack the thread, but which book is good for restoring / tuning the Europa?

[TurboFource]

I have the Wilkins book, he is supposed to be expert on Twin Cams.

[jbcollier]

Cazman, why not start a new thread?  More listers will know to comment then.  Also specify which Europa you have.  Obviously the Wilkin's book is useless for S1/2 owners.

[Pfreen]

I installed a .110 diameter orifice.  I made it out of brass.

[cwtech]

My opinion only, but I believe a full flow of oil to the head will help cool the valve stems, springs, retainers, etc.   

The higher-volume oil pump and increased sump capacity is also beneficial.

The valve stem seals will prevent excess oil being sucked down the intake guides.

[jbcollier]

Yes, engines are also oil cooled.  But, at sustained high rpm, more oil may be pumped in than can flow out.  Thus many racing engines restrict the oil flow to the head.  If you are not racing, it's not an issue.