OHC-6 TECH Over Head Cam projects, questions and advice.

          
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Old 03-10-2026, 07:18 AM
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Default Oil Line to Rear Camshaft

The attached photo shows a pair of fuel pressure regulators and gauges on my newly purchased 68 Sprint with triple Weber carbs. The right regulator is for fuel. The left regulator is fed by an oil line from the oil sending unit connection and feeds oil at 6 psi to the back of the cam cover. Can someone explain this? I have never seen oil go through a pressure regulator. I assume that the rear of the cam can become oil starved and this is a remedy?
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Old 03-10-2026, 08:42 AM
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It is probably used to reduce the volume to the camshaft oil system. On Tom Langdon's old Race engine I used to own, he blocked off the normal oil gallery to the head, (the one with the oil restrictor) and he installed a regulated oil line to the back of the heads oil gallery, in the same location as on your engine. I suspect the same thing was done on your engine, but without pulling the head there is no way to know for sure. I don't beleive it was an oiling issue to the rear cam bearing area, just the most convenient place to reroute the oil flow.
Perhaps Rob can add more as he now owns Toms old engine from the Hole Shot 6.

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Old 03-10-2026, 10:05 AM
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Does the oil line go in the cam cover or to the back of the cylinder head?

Its a little odd going to the cam cover, but in doing so would likely mean the oil passage to the lash adjusters and cam is intentionally plugged and the external line is feeding both the lash adjusters and cam "bearings" and lobes.

If it is going to the rear of the head, then it likely has a sealed off tube letting full oil pressure the cam and lobes, but lower psi to only the lash adjusters. Which is how I have mine set up.

I would prefer to have the higher volume and pressure going to the cam and keep the low pressure regulation to only the lash adjusters.

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Old 03-11-2026, 08:08 AM
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The oil line connects to the stamped steel cover at the rear of the camshaft, not the head.

Since the regulator is set at 6 psi, increasing RPM will not increase oil pressure. This seems counterproductive. If an engine oil pump is producing only 6 psi at idle most would be concerned, and even more concerned at higher RPM.

There is quite a bit to unpack about this engine and I just want to be sure there is nothing that needs correction. It will be difficult as the B-J buyer knows little about the car, and the previous owner to him and the builder remain unknown.

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Old 03-11-2026, 03:39 PM
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Wow, that makes no sense to me. Unless there is something going on under the rear cam cover plug. That would only oil the rear face of the camshaft, possible with some oil weeping around the rear cam bearing. Maybe someone else will have better insight to what it was installed for?

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60 Jaguar Mark 2, 3.8L Automatic
67 Sprint Firebird 230 OHC-6 4-Speed A/C
1971 Fiat 130 Coupe 3.2L SOHC V6, ZF 5-speed
78 Catlina Safari, Pontiac 400 powered
77 Astre Formula, 215 Buick V-8 T-5
73 Lemans Safari, 400 4bbl 4-speed
71 Catalina Enforcer, 455 4bbl
05 Dodge Magnum 3.5L SOHC V6
06 Mallet Solstice #024 LS2, Now with a Tremec 6060 6-speed!
2012 F-150 Echo Boost (My local Ford Dealer SUX!!!)
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Old 03-15-2026, 08:31 PM
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I have a correction regarding the oil line. I was able to get a better view of this today and the oil line does go into the cylinder head. It looks like it enters the top left (pass side) of the head. That is consistent with what a few of you explained.

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Old 03-16-2026, 01:50 PM
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Normal!

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Old 03-16-2026, 07:23 PM
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Makes sense now.
Oil Galley.


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