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qa1142
How and where do you hook it up?

I get how they work, where do you pipe it in on 2.0L?
jt914-6
On my six, and I'm sure on a four the outlet for my Accusump is connected to the oil pressure switch connection. I mounted a short 1/4" pipe thread straight pipe, and then a 90 degree elbow. Mounted the -6 line from Accusump to one side and the pressure switch on the top. I'm using the three quart one with a 12 volt solenoid to turn in on and off. It comes on with the key switch and gives the oil pressure to the engine before starting....

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DNHunt
Mine is under the relay board and tees into the oil return line of a full flow system.

Dave
ME733
...........I classify accusump as another "snake oil trick part of the month", a unnecessary part....which will eventually go defective and screw up your engine...I know this system has been around for quite some time...I know In an Ideal world it does what it is supposed to do...prelube the engine before starting.....BUT....the charged cannister of oil will leak down over time.(when you store the car for months at a time)....and...as a resivor in the oil system...it will refill when you START your engine...(after it,s bleed/leaked down over months of car storage)....SO when you start the engine.( you have all that excessive additional oil..1-2-3-quarts in the crankcase, which CAN CAUSE serious problems in and of itself, and you have ANOTHER 1-2-3- quarts of storage to refill ....BEFORE...the engine sees normal oil pressure to the bearings, (at low R.P.M.s)....which can be very low anyway, such as in a 911. I.M.O., and I know plenty or guys who removed them eventually,...the system is simply unnecessary...and will eventually cause you unnecessary grief......"the old saying of..KISS.. "keep it simple stupid" applies in this case.....AND if porsche (as an example) thought this system was such a great idea....They would already be in use...............My 2 cents worth....murray.
qa1142
thanks Murry

I worry same, I was not going to use the valve and let it empty when not running. I just am looking for insurance in hard corners

any other suggestions?

Will
brant
I very much disagree with Murray
if you've ever done the testing of a 4 cylinder in the corners you'll see what the real purpose of an accusump is.

I don't care about pre-oiling...
but in a race situation with a type 4, there is oil starvation

the stock 3psi light doesn't reveal that the oil pressure drops to about 7psi in the corners of any length.

at 7500rpm I don't find this acceptable.
the -6 dry sump system effectively solves this condition, but on a 4 the accusump is a cost effective way protect an expensive motor.

I've seen them mounted in race cars in the front trunk, passenger floor, and also the rear trunk. I mounted mine in the front trunk for weight distribution. You don't want any rear trunk weight on a -4 race car (I hate seeing batteries mounted there)

brant
cary
Aren't we talking about 2 different gadgets. Accusump for pressure and a catch tank for blow by from the PCV system?

You need something for starvation if your going to throw the car around. My two boys drove my 2 914's thru high school. They red lighted the cars everyday on the way home from school. 90 degree section corner they took at 40 miles an hour.

Now that dads going to freshen to cars up. That needs to be fixed. I'm thinking that I need both gadgets.
Jake Raby
These save wet sump engines. I require them on all my engines that will see track usage and retain a wet sump oiling system.

I even have one in my 996 track car. They work when plumbed correctly.

Oh, why didn't Porsche use them, well the same damn reason they didn't employ 99% of the other advancements that the aftermarket has developed. In a bone stock vehicle without slicks and hard cornering capability their use isn't nearly as effective.

Increase the stock engine's output by 100%+ and enhance braking and traction and its a whole new world.
qa1142
ok

So mine is street car, with some fun cornering and auto-X.

I just never want to see that light.....

Will putting the budget accumulator
http://www.jegs.com/i/Moroso/710/23930/100...roductId=745635

Tied into say my oil sending unit keep pressure up in corners?

Anny issue running with 5.5 qts and letting 1 qt sit in this unit when driving?

How is this solution vs letting deep sump hang below engine (which sounds like bad idea to me)

thoughts, comments?

Will
sww914
Absolutely necessary on the track with a type 4. After I went to sticky tires I destroyed my engine because I didn't have an accusump. Out of a long corner my oil light would come on for 5 seconds at least. I had a spare (better) engine that I hadn't installed. After that weekend I took the engine apart, rods knocking. My rod bearings looked like wads of smashed up pennies. ME733 doesn't have any experience with this obviously. Mine does not leak down, even if it sits for a month without starting the car.
My accusump is plumbed through the oil pressure sensor hole next to the distributor.

I never tried the Moroso unit. I thought about it but decided to spend the extra money and not worry about my decision.
ConeDodger
Very necessary on an AX or track car. I will proudly use "snake oil" on my next Raby kit motor...
qa1142
Who else makes units?
GeorgeRud
I remember running my 2.0 914 at IRP in the early 70s, and seeing the oil pressure light come on by the end of the first long sweeping turn, so there is certainly a need for more oil at the pickup in sustained cornering situations. Back then, we used a lot of extended sump kits, but the lowered clearance made them a marginal solution at best. There was a dry sump kit available back them (I think the Super Vees were using them), but that was only on race engines if I remember correctly. When the Accusumps came out, it did a reasonable job of solving the problem.

Unless you're going to be racing the car or autocrossing with race tires, I wouldn't worry about oil starvation. It probably is overkill on a street car (though anyone that has just spent the money on a rebuilt motor is understandably concerned about preserving the rebuilt motor). I'd ask Brad what his take is on the modification - I feel that he would have recommended it if he felt it was necessary for your application.

Maybe Jake would also chime in with his opinion!
Smitty911
How difficult is makine a Type IV a "Dry" sump?

jt914-6
QUOTE(Jake Raby @ Apr 4 2010, 11:01 AM) *

These save wet sump engines. I require them on all my engines that will see track usage and retain a wet sump oiling system.

I even have one in my 996 track car. They work when plumbed correctly.

Oh, why didn't Porsche use them, well the same damn reason they didn't employ 99% of the other advancements that the aftermarket has developed. In a bone stock vehicle without slicks and hard cornering capability their use isn't nearly as effective.

Increase the stock engine's output by 100%+ and enhance braking and traction and its a whole new world.

agree.gif
"They work when plumbed correctly"
I have a six and I'm not concerned about losing oil pressure in corners. My reason is to pre-pressurize the engine before start up. When you have a $8,500.00 + engine I think it's a good idea to make it last as long as possible. Getting oil pressure to the bearings before start up I think is a good thing..
I really don't think that you'll pressurize an engine by adding the oil from the Accusump into the crankcase in a four. The logical way to me is plumb it to the oil pressure switch connection. Putting oil under pressure, is what it does, will get to the bearings much quicker than through the crankcase/oil pump....Jake or someone else who knows can chime in and tell if me I'm wrong or if this is correct...
Joe Bob
I like them on 4 bangers, but don't see the need on a dry sump motor...
brant
big enought to guarantee that you blow your valve cover gaskets when you spin off track!

check here for the price is right
ME733
...........With the stock oiling system ...(not dry sumped).....there is no reason that the engine should see low oil pressure...that is to say sucking foam,or air...YOU have to think through this problem., and REALLY look at the oil pickup tube, how it,s held,sealed,and what /how the engine is assembled and with-out certain factory parts...2) then you need to look at the (not) quality oil pumps.....MELLING IS THE ONLY ONE TO USE....3)then with your ENGINE running, and hot., oil lines are full.cooler,s etc,...CHECK THE OIL LEVEL, with the dip stick provided by the factory. IF you havent figured out the fundenmental problems.....just add a deep sump, like the majority of racers do...If your still getting low oil pressure...blink several times...cause you ass is upside down...and you need to hit the kill switch....PS. to george rudd....Yes george, all the sucessful, professionally built FORMULA SUPER VEES had a dry sump system.P.S. to sww914..YES mcafee DOES HAVE experience with accusump., and have removed as many defective ones as I have installed per customer request..........GENERAL P.S....when the accusump fails..the 3-4 quarts of oil wind up in the crankcase., can and will /wind up flooding cylinders with OIL...then when you crank the engine...well you should get the idea., DETONATION, fouled plugs, unseated rings,broken rings,etc etc...BUT IT,s YOUR life and money so just do what the hell you want to do....my 2 cents worth.
brant
low oil pressure on race motors is not the cause of inferior parts, or assembly...

it is due to cornering forces.
We have always used a special sump with extended pick up
I have had multiple professionally built -4 race motors

the oil side loads away from the pick up and the accusump allows additional volume under these conditions.

best to actually test and see the facts
I suggest (what I did) that you install multiple oil pressure warning lights of different PSI. its interesting to see what happens.. even on a fresh 10K race motor with far superior blue printed oil pumps.
Jake Raby
I've never experienced a failed accusump unit, directly or indirectly.
I have experienced failed engines that would still be alive if they would have had the added protection afforded by the accusump when properly plumbed.

Like most other things, its all in the application. The installer's attitude and level of drive has a great deal to do with the success of the unit.
sean_v8_914
who has the video of the valve covers with plexi windows. it shows the valve covers completely filled with oil in a corner.

I have been using an extended sump 1.5 qt under teh engne. I can see where a street car would have issues over big bumps in teh road. no problems with clearance on teh track...unless you miss your apex and get into the marbles and...ya'll know that story.
TGM
Hello Jake,

Could you please elaborate on "correctly plumbed in". I was very disappointed with the Accusump with regards to oil starvation. It just delayed the onset of low pressure until the worst time of full throttle acceleration and max. RPM. I also found excessive oil blowby due to momentary overfill when accumulator expells its charge. My dipstick would even blow out an inch or two after a 20 minute track session.

The deep sump is the real fix here in that in prevents pickup starvation in the first place. However, I did destroy one deep sump when we hit a crank pulley that fell off a car in front. If I could do it all over again, I would have done a dry sump system.

Thanks,

T.G.
charliew
I've used a 3 qt. accusump on a k5 blazer with a ramjet for six years. It sets sometimes for a month. It has never lost it's charge. I usually try to remember to rev it a little before I shut it off to store more pressure than it will have at idle. It always primes to at least 30 psi when I turn the key on. The refilling after a oil change happens fast as the pump puts out way more volume than the bearings need. How could it possibly overfill the crankcase while the motor is running by pushing oil through the bearing clearances? Actually I think the reccommended line size is 5/8 supply to the motor gallery to make sure it provides enough volume at enough pressure. 10 psi at 1000rpm-70 psi at 7000rpm. How can it fail? The ign sw circuit turns the valve on and off. I can see where 3 qts overfull in a t4 would be a problem though, maybe a 1.5 qt one would be a better fit. Also the high oil temps of the aircooled motor might be a consideration but I trust Jake on testing and would believe what he reccommends for the t4.
jt914-6
I'm not Jake, but I think he would tell you the same thing. The Accusump on a six or a four needs to be plumbed to the oil pressure switch inlet on the engine. If you have low oil pressure that is the most direct way of getting oil into the motor and to the bearings when you NEED it..... shades.gif
jhadler
QUOTE(ME733 @ Apr 5 2010, 06:14 AM) *

...........With the stock oiling system ...(not dry sumped).....there is no reason that the engine should see low oil pressure...that is to say sucking foam,or air...YOU have to think through this problem., and REALLY look at the oil pickup tube, how it,s held,sealed,and what /how the engine is assembled and with-out certain factory parts...2)


I beg to differ. The lateral loads on a car shod with sticky race tires (I'm talking -race- tires, not spiffy sporty street tires) will easily slosh the oil away from the pickup tube and temporarily starve the motor. Running an extra half-quart of oil is barely a band-aid. Yes, it will raise the threshold of the effect by a small percentage, but not enough to be effective. Adding the tuna-can sump extension helps a lot more, as there is greater volume of oil retained around the pickup tube when the car is under large side loads. But this only works for very short durations (slaloms etc.). Big sweepers in cars with high grip levels -will- starve this pickup as well. While I don't have an accusump routed into the car -yet-, it is in my short term plan to do so.

QUOTE
then you need to look at the (not) quality oil pumps.....MELLING IS THE ONLY ONE TO USE....3)


Okay, while I don't have the depth of data that Jake has, I can say upon my own investigations that the Melling is probably -not- the pump to have. All QC aspects aside, the Melling is a steel body that fits inside an aluminum bore. Aluminum has a coefficient of thermal expansion roughly 60% greater than Steel. This means that while the pump fits in the bore nice and snug when everything's cold, the heat of a running motor will dramatically grow those tolerances. Lots of pressure can now bleed directly from the outlet of the pump right back into the sump and never make it to the bearings.

-Josh2
Dave_Darling
With street tires, you can also get the oil light on. It just takes longer turns to do it. (About 2 1/2 on- and off-ramps in a row in at least one case I know of.) The "tuna can" plus running a little over full is good enough for just about anything you'll see if you're using street tires. It seems to be effective for most autoXes, even on sticky tires, due to the relatively short duration of corners there.

Once you get to the Big Track on sticky tires, you need a dry sump or an oil accumulator.

--DD
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