hi all

does anyone have any experience with oil accumulators? hype or good idea??

http://www.moroso.com/catalog/catego...?catcode=13600

I am considering this for my 408w race engine as insurance for oil pressure drops in serious cornering.

any help appreciated
cheers
Oz

 

We use one on the race car. Only good for start ups, puts oil back into the bearings. If your oil pressure goes down while driving it wont help....

 

+1 you use an oil accumulator for startups, for road racing get a moroso 9 qt road race oil pan i use it on myrace engines mostly 351 w'salong with a 2 filter oil filter relocation and oil cooler, you can put about 10 quarts of oil in your system that way, but i have never seen many people use accumulators at open track events or any of the road racing or stock car series i have participated in...also make sure you are running a crankcase vent system of some kind, i usually just have special valve covers on the drivers side head that has 2 breathers in it and a solid valve cover on the other head...also get a good oil pump and use good oil if your racing most engine problems in short track and road racing i see are bad oiling and fuel systems , i like mineral based over synthetic for racing but its your choice of what brand you trust and what they offer...

 

.....

 

thanks all

no Scott...no flying in this one, and if i am it will be for all the wrong reasons and oil pressure will be the least of my concerns!

Im just considering it from the insurance point of view and also the cold start pre-lube as the car will sit around for weeks at a time between events.

the last motor spun a bearing due to oil starvation. Thisengine is costing the kids inheritance so I ama bit paranoid about it. It will have a well baffled sump and the guy building it is pretty good (also ****) about the oil system.

I am running an oil cooler, so the filter will have to be remote anyway. Have a look at the installation instructions "A" on that link. The only additional failure point is the t-piece to fit the accumulator. If the accumulator itself fails to push oil back in you are no worse off than not having it at all. It seems pretty fool proof to me. I priced it up and it works out to about $625aus for everything i need...bout twice what you'd pay there.

Moroso also have a remote switch for the ball valve on the bottom so I can set the tankup on the inner fender and run pretty short hoses. Next question is where to mount the oil cooler itself!

btw, what is "glyptol the block" ???
cheers

 

From http://www.tatom.com/ar4.htmsimply because it cameup at the top of a search. Boldface mine.




As far as accumulators go, I have no experience. But assuming that they do perform their intended function every once in a while, they will refill as oil pressure from the pump returns. So you might want a little extra margin on the oil pump volume so that refilling the accumulator doesn't steal too much flow from where you really need it to be going.


Norm

 

Summit Racing sells pumps in different sizes. I like the idea of having 'x' number of quarts of oil under pressure just in case.

I want the other guy who said they only work on start-up to explain THAT since the ones I've seen are EMPTY at start-up, they then fill with oil under pressure from the pump and should the oil pressure in the line drop below the set pressure of the pump the oil will be forced back in to the engine. They were developed for turbos as 'coast-down' pumps to supply oil to the turbo after engine shut-down and I believe they were also used on combat aircraft. I could be wrong on the aircraft part.

 

mike there is a tap on the bottom. you have to build some oil pressure to fill the bottle, turn off the tap then shut down. on start-up you open the tap before starting the engine.

norm, you add extra oil for the accumulator. it is either emptying into the system or filling up once pressure rises again...no net change in oil volume in the whole system. But, that does raise a good question. if your oil pressure drops and the bottle empties to save your engine YAY! then what happens to oil flow as pressure rises again? the bottle has to refill so how does it stop all the oil from going to the bottle which means starving the engine as the revs come up???? It must have a small enough hole in the bottom to restrict the oil going back into it????

 

I know absolutely nothing about them Ben. Sounds like they will do what you want them to though. Nothing like losing oil pressure in the curve at 8K RPM.

 

Filling the accumulator works against air chamber pressure, so it's not exactly an uncontrolled"leak" into a zero-resistance-to-flow container as far as the lubrication is concerned. There should be some residual air pressure even with the oil chamber empty (else nothing would be available to force out the last bit of the oil under any meaningful pressure or flow rate). As you compress the air on refilling the oil chamber, its pressure rises, which will ultimately slow the flow of oil into the accumulator. Once the pump gets things back to normal operating pressure, initial filling will be slightly/somewhat faster than when it's nearly full.

Obviously, you don't want the orifice to be too small, or else flow out of the accumulator might be somewhat "lazy". My guess is that some tuning for biasing the flow one way or the other is available based on the range of air chamber volume and its pressure settings vs system oil pressure.

LINK


Norm