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Full Version: AN ALTERNATIVE TO THE TUNA CAN
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Type 4 Unleashed
I, yanked my motor yestergay, tore it down to the case, I was doing a rering and head swap, well today, I couldn't help my self, I split the case, figured what the heck, and I remembered talk on here about tuna cans. I tried one once, didn't like it.

These baffles, help keep the oil from rushing from side to side during hard corning, they actually, direct oil to the pickup, I leave about an 1/4" space on the bottom and ends, to allow the oil level to equalize in the sump, when the motor is off to get an accurate dip shit reading.

I have no pressure lose, during hard corning(i.e. green light when you go around a corner really fast).

Just thought I'd share this, and to see what opinions are provoked.
McMark
Seems like a good idea! clap.gif
Steve Thacker
I think that is a very good idea also. clap.gif

You ought to make and market those.

Our VW cabriolets have similar plastic baffles that snap onto the oil pump pickup tube, to stop/correct the same thing. They could stand to be larger like your solution, as I still once in a while get a redlight in the dash.
Mark Henry
BTDT it's old news, first time I saw it was in Hot VW's late 80's/early 90's in a FAT engine build-up article.

Tighten up the gaps and punch a few holes in the stock windage tray.
redshift
Could someone that knows, please draw a line on that picture, that represents how deep the oil is in an engine at speed.. I mean like 4500-5500..

Please?



M
machina
QUOTE (redshift @ May 19 2005, 07:09 AM)
Could someone that knows, please draw a line on that picture, that represents how deep the oil is in an engine at speed.. I mean like 4500-5500..

I don't know alot but at higher rpm's, the oil has a hard time evacuating from the heads. The picture is a TI but its the same idea.

The holes in the stock baffle help to get the oil back to the pickup faster.

I had to go to a deep sump with an accusump accumulator, the other stuff just didn't cut it.
machina
the pic..........
redshift
Thanks for that! I imagined the heads would hold onto it some.. but whoa... so, correct me if I am thinking wrong... from the looks of it, and imagining the stuff in transition... meaning what we can't see there, and what hasn't pooled back in the case..

... there is only about a 1/2 qt down there?

I hate that green light. Green means stop.


M
914werke
Good thread!
Since oiling is the lifeblood of an engine any improvements in evan stock motors are "good to know"
So is the general consensus is that ALL T4 windage trays should have such holes drilled?
SOT are the seals (green) still available for the that windage tray?
redshift
Accusump... it's just expensive sense.


M
airsix
Whoah! That's a pretty high tide there. This is a concern to me now. Based on that picture, my turbo oil return is submerged at high rpm. headbang.gif Mueller, you looking at this?

-Ben M.
Mueller
QUOTE (airsix @ May 19 2005, 09:57 AM)
Whoah! That's a pretty high tide there. This is a concern to me now. Based on that picture, my turbo oil return is submerged at high rpm. headbang.gif Mueller, you looking at this?

-Ben M.

I was going to put the turbo oil return on the top......looking at the pictures, I wonder how effective it would be to "help" the oil escape by adding lines to the bottom of the head or valve cover???
messix
wouldnt' that extra oil in the head at high rpm be keeping the heads cool.

correct me here if i'm wrong but i thought that these engines were air and oil cooled.
machina
after about two hours of track time, I have roughly 1/2 qt of oil in my puke can. It is manageable but I don't like it. And my vents are tapped at the top of the head at the standard location.

And the accusump is nice primarily for oiling before startup. The truth is that at a sustained high rpm, the sump can only supply pressurized oil for a few seconds, even if you have the 3 qt. Imagine how much oil the motor pumps at that speed, alot with a melling or even a stock unit.
machina
QUOTE (messix @ May 19 2005, 12:11 PM)
wouldnt' that extra oil in the head at high rpm be keeping the heads cool.

correct me here if i'm wrong but i thought that these engines were air and oil cooled.

Not really, and then all the oil is in the heads and that is why, or at least contributes to the oil starvation since there is much less oil at the pickup in the case.
Brad Roberts
Great thread smilie_pokal.gif

The tuna can was never a "great" idea, it just works for the average AutoX/Track guy. Now we know why 911 engines are 90% dry sump.


B
Reiche
QUOTE (messix @ May 19 2005, 10:11 AM)
wouldnt' that extra oil in the head at high rpm be keeping the heads cool.

correct me here if i'm wrong but i thought that these engines were air and oil cooled.

The bottom end is cooled by oil, but it has to circulate a lot to do much cooling. The oil doesn't circulate in and out of the heads fast enough to do much cooling compared to the air that is passing through the fins.

Even if you have oil squirters to cool the back of the pistons, they are doing less for piston cooling than the cylinder walls are.
Jake Raby
I actually sell those pieces already waterjet cut ready to be welded to the pick up tube... Its nothing new..

It will not serve the same purpose as a Tuna Can.

Most oil starvation issues are compounded by incorrect install of the oil pick up tube O ring, or an O ring that is aged and has turned hard, thus allowing air to be picked up in the tube when windage decreases the amount of oil submerging the tube...

The best fix I have found is some preventive measures coupled with the 1 quart deep sump, I sometimes even modify the sumps for even more efficiency by narrowing them and welding them back together.

BTW- The engine is not oil cooled any more than any other, your heads are not submerged in oil are they?? Proper lubrication decreases friction, which decreases heat being generated- think about it..

Cooling the oil, don't cool the heads- not even a tad bit.

A stock, non modified Windage tray can easily create oil starvation issues, that would not be there otherwise... Getting oil back into the sump from the heads is a huge key and the tray slows that drastically...The more RPM you have the worse it is.

We actually limit the oil that gets into the valve covers on race engines by welding the tips of the pushrods thus lightening them even further and this also lessens the oil in the valve covers.... Then an external oil delivery system is created that we can adjust the oil flow delivered to the valve covers with jetting changes to the orfices boldblue.gif
lapuwali
synth, are those two head pics low and high rpm, or before and after with and without the extra holes in the baffles?

914werke
QUOTE
BTW- The engine is not oil cooled any more than any other, your heads are not submerged in oil are they?? Proper lubrication decreases friction, which decreases heat being generated- think about it..


I dont necessarily agree with that statement, perhaps with the T4 design but if you take for instance the early MC GSXR mill for example at 3/4 ltr. it DOES creatively use oil to cool the head in conjunction with Finning and produces
(in my case) 132HP.

So Jake you didnt directly answer the question:in other that full race applications does the application of holes in the WT and baffles you mention benefit oil in sump retention? Im of the belief Deep sumps are not universally embraced on the street because of their potential for bottoming <!-- emo&:smash: -->IPB Image<!-- endemo -->
redshift
James, I see that as being a running motor, then a revving motor.. the sea is all quiet in frame one, then like a perfect storm.

The amount at low rpm is what scares me the most.

I have an idea, but I only have a basic understanding of the mechanics in there.

Seems to me... David, you said the accusump is about 3qts? It dumps on start, is pressurized by the system during use, and a check valve just closes the spare oil in on stop, right?

What if there was more than that 'thing' ^^^ up there... but all vertical faced surfaces.. kind of like a round cake cutter, for cutting a cake into 100 wedges... just so there is more vertical places for the oil to hang out in the case.. uhh.. anyways, a conical bottom profile, that coaxes the oil right where you want it?

Maybe it's not the best spent resources.. I was just thinking that hanging oil would allow us to overfill even more than .5qt.. because the hanging oil is static, and not included in the pressure reading... untill you.. idle... and then.. you need a puke bottle... and ok, it's the dumbest idea ever!

Nevermind.

M
Jake Raby
The sump on my 2316 Hybrid hasn't bottomed yet... I live on a dirt road that climbs the side of a mountain and has rocks bigger than the 914 that I crawl over twice a day on average. The sump is firmly attached to the ase, unlike a tuna can that hangs off the pick up tube only. My deep sump hangs les trhan 1/4 lower than the engine mount bar.

As for the engine being oil cooled:
I have accomplished testing on the dyno with engines that had a super amount of oil in the valve covers and the same test with hardly any- head temps did not change even after a full 40 minute test. It is possible to have heads running at the melting point and oil thats only warm at best, they are impacted by different forces and not dependant upon each other.
machina
QUOTE (lapuwali @ May 19 2005, 12:34 PM)
synth, are those two head pics low and high rpm, or before and after with and without the extra holes in the baffles?

I don't remember where I found those pics but I'm pretty sure it was a stock TI at idle and then at about 4000rpm.
machina
QUOTE (Jake Raby @ May 19 2005, 02:13 PM)
The sump on my 2316 Hybrid hasn't bottomed yet...

I was really worried about the deep sump but so far it has been fine. It does hang lower than the engine bar but I have been off course with it and even hard over the gatorbacks and it is no worse for the wear.

jake mods his so it is smaller and has better clearance than the stock 1.5 qt sump I have.

Realize that the Tuna Can is attached by the center bolt in the case bottom. That area is very delicate, if you over tighten that bolt you can crack the case. The SCAT style sump mounts with a big 1/4" steel plate to the bottom of the case where the aluminum is super thick. I have heard of guys bottoming out on the sump with no damage. That said, I'm sure you could rip the entire case in half if you did hit hard enough.
URY914
Just a side note...
At this weekends a/x I had a lot of oil blow into the dump can/overflow/breather bottle.
(People call it different things, you pick a name). I ran 6 runs and I rev the shit out of it. I can hear the valves float off the rockers, that way I know when to shift.

I started with the oil level just over the top mark on the dipstick. I just checked the oil level and I'm now an 1/8" below the bottom mark. When I drained the breather bottle, I filled up a 20 ounce Coke bottle.

Also I have a real tired engine and I'm sure you could throw a cat pass the rings. But when I'm making a 1.5 g, 180 degree turn, my outside head is filling up with oil and getting blown into that can.

I have a tuna can, but need a deep sump.

All this really doesn't mean a whole lot to this thread but I just wanted to share it with my friends. wub.gif confused24.gif

Paul
Mueller
interesting Paul...now is there anything that can or should be done about the oil in the valve cover area????




URY914
QUOTE (Mueller @ May 19 2005, 01:22 PM)
interesting Paul...now is there anything that can or should be done about the oil in the valve cover area????

my breather line attach to my vlave covers. I think you can see them here.
Maybe they should be on the top of the v/c instead ofthe bottom? confused24.gif
URY914
Here's the can...
URY914
Update:

My line on the left v/c is connected at the top.

The right side is closer to the middle of the v/c.

The 180 degree turn was a let hand turn so my right side v/c was getting a lot of oil running to it.

But the good news is the right side v/c is dry, with no leakage of oil.
The left side had oil leaking out of the top of the v/c to head surface area. screwy.gif

Paul
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