The Silver Buick's 1969 Firebird OHC six project.

[milner351]

Love it

[OHC 6 Sprint]

There are a few other locations that could be used for tapping into the lash adjuster oil gallery after the regulator. Each has some merit, but two in particular have more appeal (to me, anyway).

In this picture, I would think #1 and #6 would be the two best choices ... at least from a fabrication point of view.



Most of the others would interfere with the spark plugs and wiring unless you got overly creative with fittings and regulator mounting. #3 looks promising, though.

#7 is the oil feed for the top end. It sees oil pump output pressure. That will keep you from trying to plumb in at the head bolt located between #2 and #3 since that's where it meets the "up" pipe inside the head. BUT ... that could be where you wanted to tap into the system to get your pressure feed, rather than "T" off the oil pressure sender switch location. Food for thought.

[TheSilverBuick]

Thanks for the diagram. I really don't like over the spark plugs from both a functional and aesthetic point of view. #6 would concern me with possibly cracking the freeze plug bore while drilling, though #3 I would not have that concern with. #1 I have concerns about interfering with the heater hose installation and really don't want it up against the timing belt cover.

As long as I'm not too concerned about the distributor I do like #3. I'm still interested inbetween the threaded bracket mounting bosses next to #5, where I think I'd intersect the oil galley before the tube insert.

[OHC 6 Sprint]

#6 would concern me with possibly cracking the freeze plug bore while drilling, though #3 I would not have that concern with.

Seeing all the machined and tapped holes in the head already, I'm not sure that should be a concern, but point taken. #3 looks more inviting than #6 when you look at the side view with the distributor in place.

#1 I have concerns about interfering with the heater hose installation and really don't want it up against the timing belt cover.

That's the temp sender switch location, and it is behind the A/C mount bosses - not the timing cover.

As long as I'm not too concerned about the distributor I do like #3. I'm still interested in between the threaded bracket mounting bosses next to #5, where I think I'd intersect the oil galley before the tube insert.

You'd be trying to thread an impossibly small needle with that approach.

[OHC 6 Sprint]

Ah, I keep forgetting that you're planning on direct mounting the regulator. I'm over looking its form factor in my thoughts.

[DanStokes]

It's VERY COOL seeing you guys with similar interests in a relatively obscure engine thinking your way thru this build with real help and respect. Good for you guys!

Now if we'd just get a M-B OM617 Diesel engine guy on here........

Dan

[Mater]

sweet i look forward to it being in the car

[TheSilverBuick]

I went out and looked more at the oil return issue today. The hole at the top is smaller than the hole in the bottom by a fair margin. I didn't measure the upper hole but it looks like a 7/16th 1/4-18 tap would work fine on it, but the bottom one is a 5/8th ID and I don't have anything big enough for that, nor does the town of Ely, especially with a flush sitting plug. Unfortunately a sleeve definitely will not work as shown in the picture below.

I'm inclined to tap the upper opening and use a standard 7/16th 1/4-18 plug with a hex or square head, then either use a 5/8th freeze plug in the block (has to resist 10-15psi) or tap the block with the appropriate size threads and install a square head plug that the head of the plug will sit in the oil return hole of the head like an extra "loose" dowel.

Another idea I had is I have some 5/8th OD solid metal rod stock and cut a piece to jam in there. Then mark the point showing in the head bolt hole with paint or anti-seize, pull the rod out and grind a notch in it until it gives the head bolt enough clearance then black RTV the heck out of it and slide it in. May or may not get a perfect seal, but likely would be sufficient for 10-12psi of oil pressure and if it leaks be low enough volume that the regulator wouldn't have a problem delivering and managing it.

Oh, and I see why simply moving the regulator forward one head bolt, to the place I mentioned next to #5 in OHC 6 Sprint's picture, next won't work, as it intersects main oil pressure first. My new favorite location is looking like the spot above the big freeze plug.

That's a 7/16ths deep socket that fits smoothly but not loosely in there.

[TheSilverBuick]

Ah, I keep forgetting that you're planning on direct mounting the regulator. I'm over looking its form factor in my thoughts.

I really shouldn't be opposed to using a regular bracket mount and a hose. I could elbow a line from #1 pretty easily and still mount the regulator in the middle of the engine.

[Monk]

Damn Randall you've got some engineering to do here.
Love it though when a plan comes together.

[Bob Holmes]

Just want to voice a pet peeve, and then I'll go back to shutting up and reveling in your progress.

One should not "gasket match." Most gasket's openings are far larger than approprite for a proper port to intake match. So when gasket matching, you produce an induction shape that runs down a manifold runner, "wows" out...expanding out to meet the gasket and then restricts back down to meet the dimensions of the intake port runner. This is not good form.

[TheSilverBuick]

I'm building my own tube intake for that head, it will taper appropriately.

[milner351]

Randal - not sure of all the oil system details, but - if you used hydraulic hose instead of hard lines for the oil - would it open up the possibilities? Hydraulic hose can be made into any length with a myriad of ends to facilitate just about any situation - and the pressure rating is many times more than an engine lube oil pressure system will run.

[Deaf Bob]

^^^a good idea here^^
We use braided line for fuel line as the tank is behind the driver on the driveline hump, snaking thru the firewall.. Even kinked one section between the floor and battery box, with no flow restriction... Had a hudraulic shop make it up... Just tell them what you want it for so they give you the proper inner lining for your use..

[TheSilverBuick]

We're only talking 10-12 psi, it wouldn't need anything fancy for a hose, I simply don't want one.