Accusump installation
Discussion
Advice from Think Automotive
www.thinkauto.com/accumulators.htm
The factory method is not ideal for the instalation as the oul return is the wrong side of the one way valve in the filter (option B)
Altough this works, it is better to install the accusump after the 1 way walve in the filter for full protection (option D).
Personally I would not install the accusump as per factory I would opt for a remote filter and tee it in the return the other side of the 1 way valve in filter.
This is more cost effective than a 1 way poppet valve for -10 pipe
>> Edited by adequatespeed on Friday 19th November 15:08
www.thinkauto.com/accumulators.htm
The factory method is not ideal for the instalation as the oul return is the wrong side of the one way valve in the filter (option B)
Altough this works, it is better to install the accusump after the 1 way walve in the filter for full protection (option D).
Personally I would not install the accusump as per factory I would opt for a remote filter and tee it in the return the other side of the 1 way valve in filter.
This is more cost effective than a 1 way poppet valve for -10 pipe
>> Edited by adequatespeed on Friday 19th November 15:08
Has anyone had an Accusump actually discharge and save engine due to lack of oil at pick-up under cornering or braking? I'm not convinced you need one or if it would work anyway. The pre-oiling is a good idea but not essential and if you're going to get serious (ie slicks) a dry sump is what you need. With a decent road race wet sump (baffles and trap doors) and proper oil fill I think unlikely to have oiling problem on road tyres.
You would never know if the accusump had saved you or not.
The whole idea is that you never lose pressure so there will be nothing showing on the dash.
The line I take is that the factory fit them to all the cars they build and no manufacturer fits something they can save cost on. I expect that somewhere in the dim and distant past they had an engine go pop or at least had some scary oil light moments.
Steve
The whole idea is that you never lose pressure so there will be nothing showing on the dash.
The line I take is that the factory fit them to all the cars they build and no manufacturer fits something they can save cost on. I expect that somewhere in the dim and distant past they had an engine go pop or at least had some scary oil light moments.
Steve
gdr said:
Has anyone had an Accusump actually discharge and save engine due to lack of oil at pick-up under cornering or braking? I'm not convinced you need one or if it would work anyway. The pre-oiling is a good idea but not essential and if you're going to get serious (ie slicks) a dry sump is what you need. With a decent road race wet sump (baffles and trap doors) and proper oil fill I think unlikely to have oiling problem on road tyres.
Simple answer is yes.
whilst running my car in I saw my oil pressure drop to psi in a sharp braking backroad incident. The only reason I saw this was due to having the STACK dash which has instant response. A normal dial wouln't have detected the drop it was so fast.
The engine was an AS unit and came with a big wing canton sump fitted.
Obviously in this scenario this was not a problem but I only ran the car for 500 miles of the running in period without an accusump and never saw anthing like this happen after it was fitted.
However if it can do this while full of oil and in noraml driving, what could it do on track?
I know little about all this, I'm a doctor, not an engineer :-)
However I remember reading a load of stuff about Accusumps a while ago on Blatchat that I found quite interesting.
However I remember reading a load of stuff about Accusumps a while ago on Blatchat that I found quite interesting.
That was a good read.
I still believe the Accusump is working for us as it is maintaining a pressure, direct to the oil galleys, when the pump is not picking up oil.
What I don't know is how good the Chevy pump is at pumping air. If it does pump air then that has to move through the system and come out somewhere. Even if the Accusump has done its job the air is going to pass very soon afterwards.
In the SBC the oil goes up to the cam (then the lifters and rockers) before coming back down to the main and big end bearings. I would like to hope that the air escapes at the cam or lifters but sods law says it won't.
If the pump does lift air (a point I will research) then an anti cavitation tank would seem to be a valid safeguard.
A further thought, if small air bubbles are produced (froth) during a good thrashing (as you do) then this will at some stage find it’s way into the Accusump. The air will rise and be trapped in the top of the cylinder. With this in mind it would be a good idea to allow the Accusump to empty itself, with the engine off, once in a while to clear any trapped air.
Another thought, if the Accusump has done its job it has emptied some or all of its contents and the pump is again submerged. The air picked up by the pump will now be heading to the cooler then back to the engine oil galleys. What are the chances that the Accusump is now recharging and the air goes in there? I think sods law comes into play again.
Steve
I still believe the Accusump is working for us as it is maintaining a pressure, direct to the oil galleys, when the pump is not picking up oil.
What I don't know is how good the Chevy pump is at pumping air. If it does pump air then that has to move through the system and come out somewhere. Even if the Accusump has done its job the air is going to pass very soon afterwards.
In the SBC the oil goes up to the cam (then the lifters and rockers) before coming back down to the main and big end bearings. I would like to hope that the air escapes at the cam or lifters but sods law says it won't.
If the pump does lift air (a point I will research) then an anti cavitation tank would seem to be a valid safeguard.
A further thought, if small air bubbles are produced (froth) during a good thrashing (as you do) then this will at some stage find it’s way into the Accusump. The air will rise and be trapped in the top of the cylinder. With this in mind it would be a good idea to allow the Accusump to empty itself, with the engine off, once in a while to clear any trapped air.
Another thought, if the Accusump has done its job it has emptied some or all of its contents and the pump is again submerged. The air picked up by the pump will now be heading to the cooler then back to the engine oil galleys. What are the chances that the Accusump is now recharging and the air goes in there? I think sods law comes into play again.
Steve
canam-phil said:
Someone should fit a remote pressure gauge on the Accusump accumulator and see if the pressure falls.
Can't see there being any doubt that its worth having along with a good design sump without going to the dry sump option.
The Accusump is open to the oil system so should read the same pressure (within normal tolerances) as anywhere else you care to measure it.
Steve
This thread is very interesting reading. I am intending to try and get TVR Power to help me fit one to a speed 6 as I think it would be a very good safety system for startup. www.pistonheads.com/gassing/topic.asp?t=138157&f=13&h=0 would you guys agree? That sound of metal on metal on a dry sump really worries me! I was thinking of the www.accusump.com ignition linked one. Any advice greatfully received.
maddog-uk said:
This thread is very interesting reading. I am intending to try and get TVR Power to help me fit one to a speed 6 as I think it would be a very good safety system for startup. www.pistonheads.com/gassing/topic.asp?t=138157&f=13&h=0 would you guys agree? That sound of metal on metal on a dry sump really worries me! I was thinking of the www.accusump.com ignition linked one. Any advice greatfully received.
As you say the Accusump will do nothing for you during normal running as the dry sump is dealing with that. It will work for the pre-oil on start-up but you will need to install a one-way valve so that it is not trying to fill the reservoir rather than the upper oil galleys. The electric solenoid valve will be wired to the ignition so will close trapping the oil when you switch off. On start-up you turn on the ignition and just pause a moment before hitting the start button.
Steve
steve_D said:
Someone should fit a remote pressure gauge on the Accusump accumulator and see if the pressure falls.
Can't see there being any doubt that its worth having along with a good design sump without going to the dry sump option.
The Accusump is open to the oil system so should read the same pressure (within normal tolerances) as anywhere else you care to measure it.
Steve
I should have been more specific. I was alluding to the lag on the standard gauge and to fitting a fast response mechanical or electrical gauge connected to the air side. OK, Stack is fast but my Ultima gauge reacts too slow to see whats happening.
Gassing Station | Ultima | Top of Page | What's New | My Stuff