[GTOWAGON]

Ok who can give me all the details on an external regulated oil feed for the lash adjusters
1. best place to take the oil from and best place to get it in to the lash adjusters

2. What regulators work best

3. Best size line to run to lash adjusters

4. After this mod what oil pump pressure is best

5. Is 15 pounds correct for the lash adjusters and at what rpm as I assume the pressure is increasing with rpm

6. What is the minimum oil pressure the lash adjusters require

Thanks

[TheSilverBuick]

My learnings.

Take the oil from the oil pressure port off the oil pump. Use a relatively small line out to the regulator. I think I used 3/16th. Then have a relatively large line as the return from the regulator, I used 3/8th. Knowing what I know now, I'd port the oil right into the head at the rear oil galley plug. I was told a 90º wouldn't fit between the engine and firewall in a Firebird, but I'm convinced it will now that I have an engine in the car. I do not believe any dead headed pressure regulator (no return line) will work due to the pressure differential needed, but maybe playing with line sizes could get that to work.

I put a trimmed Buick high pressure spring in the oil pressure relief and dial the regulator down to cap out around 12-15psi with thick oil. It hovers around 7psi at hot idle. Main pressure on mine is now 55psi, and that was function of trimming, it was in excess of 70psi with an unmodified spring. I could put a few washers in the cap and up it some, but I'm comfortable with it at 55psi. I adjust the viscosity of the oil to meet a target of 35-40psi at cruising rpm.

Don't forget, if you are running an external line you have to close off the restrictor tube hole to the lash adjuster galley, or replace the restrictor tube with a piece of pipe. Some have simply soldered the hole closed, just make sure the solder job is good and won't come loose!

I'm running a straight pipe in place of the restrictor tube, but I think the next time I have the engine apart, I'm probably going to put a restrictor of some kind in as I think I'm getting too much oil up top. I'll probably measure the tube and shoot for half that area. Still will be significantly larger than stock. And technically the restriction is the center bearing journal of the camshaft, which I haven't measured for area.

[GTOWAGON]

Thanks for the information once again I think that since the engine is apart I am going to go ahead with this mod

[TheSilverBuick]

Also, iirc, the hole the restrictor tube sits in is NOT cylindrical. It has a very slight taper to it. Basically meant that I put an interference fit (hammered in) tube in the hole.

I used ultra black rtv as a sealant, then blew out the oil galley with brake clean and compressed air after the sealant dried. Though honestly, if it leaks a little, it'll be an internal leak and have almost no pressure impact due to low volume of fluid. Basically, no real need to over think it. Or just use a soldered up restrictor tube.

[GTOWAGON]

So where did you end up tapping into the lifter gallery I can't tell in the video and are you just using the oil sender port for your feed

[TheSilverBuick]

Don't follow my lead on the lifter gallery! I won't be doing that again knowing what I know now. I drilled in through the side of the head right into the oil galley, except I unknowingly intersected an oil return passage. Fortunately it was pointed out to me before I put the head on, otherwise I'd of had zero oil pressure the lash adjusters. I ended up putting a pound of JB weld into the head backfilling the oil return drain.

The rear of the head is the best place to feed into the lash adjusters. And yes, I have a simple tee off the oil sending unit port, one end with a 3/16th(?) line running to the pressure regulator and the other to an oil pressure sensor.

[GTOWAGON]

What regulator did you use

[scooter1966]

I am running similar to TSB, tee off the oil pressure tap from oil pump, to 1/4 brake line to regulator then to both the front and rear lash ports in the head. set to 12 psi.


regulator used

https://www.summitracing.com/parts/hly-12-840/overview/

[GTOWAGON]

I have looked at those but am worried about the 9 psi limit I would also like a bypass regulator as I am just running into the rear lifter gallery plug and will run the return line into the pan

[TheSilverBuick]

I tried a cheap e-bay one, then ended up getting a $90 Aeromotive fuel pressure regulator, and ran into the same issue I had with the cheap one, namely wouldn't drop the pressure enough. I ended up reducing the feed line from the oil pump to the regulator to get the pressure down to ~5-15psi. I wonder if the reduced feed line would of allowed the cheap e-bay one to work. I may retry it on my next engine build... Hopefully this summer?

[GTOWAGON]

What size feed line did you end up with

[GTOWAGON]

I also found a neat 90 for the back of the head it's 3/8 male pipe and 1/8 female and is only about a 1/2" tall edelbrock makes it.
It's perfect for the lifter gallery plug in the back of the head

[GTOWAGON]

I have been looking at the aeromotive 13003 regulator with the bypas and also the Holley regulators since you had a hard time getting the pressure down so you think that a 3-9 psi regulator would work better

[Bzltyr1]

Originally Posted by GTOWAGON

I have been looking at the aeromotive 13003 regulator with the bypas and also the Holley regulators since you had a hard time getting the pressure down so you think that a 3-9 psi regulator would work better

I put a pressure relief valve in the back of the lifter/follower galley. Very simple. It took a little plumbing work.

I have almost 50 psi but only 17 in the head. No other change were necessary. I may take SilverBuick's advice and install a Buick oil pressure spring.