atb

This thread has been started to pick up the conversation in Rob's race car thread ("So I bought a track car...") regarding using accusump type system to help our cars in track situations.

Other oiling issues are welcome, buts lets keep the primary focus an addressing the one oiling issue that an accusump can help with, temporary exposure of the oil pick up on high g loads.

It would be good to see what kind of systems people are using, and how they are integrating them i.e oil filter sandwich plate, a "T" somewhere in the oil cooling system, or tapping into the block.

If you have one installed, please share the installation details, and what components you used and why.

I would like to see discussion on monitoring oil levels, and how you avoid having too much oil collect in the sump, etc.

hacker-pschorr

Here you go

https://rennlist.com/forums/928-foru...-question.html

https://rennlist.com/forums/928-foru...-pics-and.html

https://rennlist.com/forums/928-foru...accusumps.html

https://rennlist.com/forums/928-foru...placement.html

https://rennlist.com/forums/928-foru...questions.html

https://rennlist.com/forums/928-foru...placement.html

atb

I don't believe they are an RL sponsor, so I won't post a link, but Canton Racing Products seems to be the main producer of accusump products. From what GB mentioned in the other thread, the 3 quart version with an E.P.C. (electronic pressure control) valve would be the best set up for a race prepped 928. Any have this system mounted?

atb

You and your fancy-shmancy search functions....

atb

In reviewing the above threads, I still didn't see an answer to the elusive question of which EPC (which pressure range) is best for our application. Anyone have any input on this?

Also, does the sandwich plate work, or is it too restrictive as mentioned in the other thread to function properly on the track?

MGW-Fla

Carl's set up he sells with the Canton Accusump uses Canton's 20-25 psi electric valve. Canton also sells valves with 35-40 & 55-60 psi for their 3 qt unit.

Carl's package:
http://www.928motorsports.com/parts/accusump.php

Canton's 3 qt Unit & accessories:
https://www.cantonracingproducts.com...-3QT-NO-VALVE/

Carl Fausett

I sell the kit with the EPC valve, and I use it myself.

Have been an Accusump user since 2004. Early "automatic" systems had a tendency to over-fill the sump in certain situations on race day. I know it happened to me a couple times and I think Jean-Louis too. The oil-accumulator concept took some hits in reputation back then for that.

If memory serves, the EPC valve was introduced by Canton in about 2008. I upgrade to it right away and it has been a no-problem system ever since. I turn mine on with the ignition. I have two main switches - one that starts the fuel pump(s) and then the one that turns on the ignition.

When the ignition turns on, the Accumulator provides pressure to the bearings before the engine is cranked.

Here is the page that explains the valve options:
https://www.cantonracingproducts.com...&category=2425

atb

Thanks for the input Carl. This may be obvious to everyone but me, but I don't understand what the PSI rating is referring to. Is it referring to the threshold where the valve opens and the oil is released from the accusump?

So for the 20-25 psi electric valve, when the oil pressure gets below that range (approx 1.5 bar) then the valve opens and releases the oil from the accusump tank until 1) the accusump cylinder is empty or 2) until the psi electric valve sees oil pressure above that range again and then closes?

Carl Fausett

Your understanding is about right. They offer 3 different pressure opening ranges. 20-25 psi; 35-40 psi, and 55-60 psi. I favor the 20-25 psi valve as it does not open to add oil until or unless engine pressure drops below that point. Because of my previous experience with the early design overfilling my sump (and getting black-flagged for blue smoke as a result) I would rather it add oil only when I am sure I need it.

The belching blue smoke/overfilled sump does more harm than just the inconvenience of missing an event. Remember that over-filling the sump is also harmful to your engine. Should the level in the sump rise into the rotating assembly the rods and counter-weights will beat the oil and whip air into it. Air bubbles in the oil greatly reduce its ability to carry loads and to carry heat away. It only takes 30% entrained air in the oil to cause rod bearing damage.

A variable you may want to consider when selecting an EPC valve range is whether or not you are running a crank scraper and windage tray system.

I like the lower pressure valve on engines with that have a full crank scraper and windage tray too. Because it closes already at 25 psi, I like to think it has less chance of over-filling the sump.

If the customer's motor does not have crank scraper and windage tray, then I prefer the next valve up, which will cycle at 35-40 psi. It will open sooner as the oil pressure in the engine starts to drop, but it will also close later when the oil pressure starts to climb again.

I bet either of these two pressure ranges would be OK for the 928. The 55-60 psi valve does seem too high for my liking.

The Fixer

Other oiling issues are welcome, buts lets keep the primary focus an addressing the one oiling issue that an accusump can help with, temporary exposure of the oil pick up on high g loads

Adam, where could we also discuss true dry sumping of the 928 motor?
That would be what i'd be interested in seeing..even drawings.

Crankcase Ventilation Upgrades for the different model years and any modifications by way of machining of the heads to help drain oil back to
the sump (wet or dry) would also be important to discuss further for
all of us newbies. Design drawings are great in explaining ideas.

The high rpm/Gs oiling issue or problem is multifaceted.

Lizard928

40 PSI is 2.72 bar.
With MS (or any aftermarket EFI system) you could turn on the EPC with an RPM trigger. So only turn on above 3K RPM (or) where you know you would be at 3 bar all the time and avoid the system overfilling the crankcase.
Given how you would drive on the track this would pretty much eliminate the problem of overfilling the sump, and running dangerously low on oil pressure before the system injects the oil.

justaguy

I run the 3 liter accusump and have good results since I started using it. My understanding is that the EPC valve controls both the discharge and the refilling pressure which is important because you don't want the accumulator refilling before the engine is back up to pressure. So a higher pressure rating EPC valve will discharge sooner and refill later than a lower pressure EPC valve.
My EPC valve # is
SET 57R
22426
33707
I have blown a motor that had a working Acccusump installed but it was a dropped valve not an oiling related failure.

justaguy

epc valve

justaguy

I got this info from the Accusump literature that came with my accusump I will give them a call tomorrow to verify it's accuracy the only way That I can see the system working like that is with a pilot to open check valve the EPC may or not server that function. I hope I haven't confused anyone The higher pressure oil in the accumulator may factor into the equation as well.

BC

Adam -

Do you remember a thread along time ago in a forum far far away (okay... here) that was about how by the time the oil pressure sensor "sees" the low pressure for the Accusump to actually trigger - that the low oil pressure has already "been in" the area of the bearings for long enough to cause damage?

Is anyone understanding the point that may have been making? Does anyone remember the thread?