I thought I would share my plan here and solicit any feedback before I'm too far committed...
I'm adding an Accusump to my oil system to hopefully help prevent any future oil pressure drops. I've gone back and forth on the best way to mount and route everything. I've spoken to Canton a couple of times, and Gerno and I have been going back and forth since he is doing the same thing with a slightly different setup.
My initial thought, after researching some LS and Corvette forums, was to use the metric plug at the front of the engine which feeds directly into the oil galley, right after the oil pump outlet. This would be a very convenient place to tap into with just a single adapter and hose from the Accusump itself. I thought I was done...
After much more research, there is a lot of mixed thoughts on this topic. But general consensus and the word from Canton themselves is that you want to feed the Accusump with a supply of oil that has already been filtered. Additionally, Canton suggests, although doesn't require, a check valve in the system. It seems questionable as to whether the oil pump itself is the best option to act as that check valve.
I found several people that suggest the oil filter itself can act at the check valve. That makes sense, as they have one internally. Currently, I'm just using the filter on the block in the stock location. The problem with that is that I don't have good access to a port after the filter. I would have to replace the Mocal thermostat which I use (not desirable) or tap into the oil pressure port on the valley cover (also not desirable, purely from a line routing issue in my case).
So I've decided that I will add an external oil filter. It's a good idea anyway for me to filter before the cooler, and I can use a larger filter vs. the small one the stock LS location uses. As I've been thinking about it, I'm actually leaning towards using them both. I don't see a real concern about doing this, unless it causes too much pressure drop in my system. I'll monitor this and see once I have it all together. But if I use an external filter with a higher particle rating (ie: it catches less debris), then having the second filter with a smaller particle rating may be a good thing in general.
The other issue for me is packaging. I have the perfect spot to mount the Accusump right in front of the engine behind and below the radiator. I'll make some mounts which attach to the cross tube which contains the sway bar. It will point directly towards my oil lines to and from the cooler, making the tee easy.
Mounting the external filter will be tricky. I want to frame mount it right in the path of my current lines, but there isn't a great spot where I have clearance under the frame rails between the sway bar and the lower control arms. I'm going to try and mount it such that it's basically beside the rack and pinion gear, but that's going to put it above the LCA mount. I may run a shorter than suggested filter here, which is another reason I like the 2 filter idea.
With all of that, here is the list of items I'll be adding:
- 3-quart Accusump #24-006
- 35-40 PSI Electric Pressure Control Valve Kit #24-273
- Canton's Billet mounting clamps #24-210
- A.R.E Oil Filter Mount #4010
- Fragola 90* -10AN Hose Ends #109010-BL
- Fragola -10AN Tee Adapter #482610-BL
- Fragola -10AN Straight Hose Ends #100110-BL
There's more, but that's the most of it. Here are a couple of pictures of what I'm using:
(I'm going to coat this thing black instead of leaving it blue)
The adapter fittings are all black now.
Now, here is my plumbing plan. I'll explain it after the picture:
Oil will travel from the pump through the galley in the side of the block to the Mocal thermostat output. That line will connect to the input of the oil filter mount. The output of the filter will go through the core support and to the input (top) of the oil cooler. Oil exiting the cooler on the bottom will travel back through the core support to a -10AN tee fitting. The Accusump input/output will connect to the tee also. The output of the tee will feed back to the input of the Mocal. The oil will then go back through the galley of the block and into the stock-location oil filter. Oil finally exits that filter and enters the block.
This seems the best path that I've come up with. The one question I've not gotten a clear answer to is whether to feed the oil cooler from the bottom or the top. My cooler is a 2-pass cooler with both fittings on the same side. PRC who made it says it's up to me, that they don't specify top or bottom input. I could argue it either way.
I plan to change the location of the pressure control switch for the Accusump. They have a fitting to mount it to the valve of the Accusump such that it measures input right at the Accusump. I, instead, plan to mount the switch on the 1/8" NPT fitting of the filter mount which taps into the filter output. This way, if the pressure ever varies there, the Accusump can immediately enable the valve to pressurize the line. Canton agreed this was a good approach, but it's not obvious how much of a difference it would make. The switch will be before the oil cooler, and the valve after.
I'm going to wire up the signals to the pressure switch to be supplied from a Bosch relay that is controlled by my Holley HP EFI. I will enable the relay in 2 cases:
- Power on, but RPM < 450 (engine not running or starting)
- Engine running and RPM above 2000
I'm doing this because the expected oil pressure at idle will probably be < the 35-40 PSI threshold of the pressure switch. Thus, I want to engage the Accusump when I know pressure should be above that threshold. The first condition will allow the Accusump to perform pre-lube duties also.
Finally, here is a picture of where I plan to install things. Like my MS Paint-work?
That's my plan. I've read a lot of threads on pre-lube and Accusumps now, and I think that pulling all of that information together into this should be a good plan. As always, comments welcome.