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blabla914
I'm purely interested in the oil control of these two tanks under high cornering loads.

I have a vellios tank purchased from patrick motorsports about 3 years ago. I understand some of the EARLY vellios aluminum tanks had oil control problems, but it was fixed quite some time before I bought mine.

However, at the last autocross I caught my oil pressure gauge jumping around. As I came off a medium speed (about 4000rpm in second) corner I saw the oil pressure gauge make a BIG wiggle. I took it a bit easier the rest of the run and I didn't see it do it again. The car had been idling for at least 15-20 min and had roughly 170F oil temp. I also ran the motor at like 2000rpm in staging a bit to make sure the scavenge pump had a chance to empty the case. I verified the level after the run and it was overfull. I can't get the hang of adding oil to this thing to save my life. It's usually a little low when I show up at autocrosses (it's generally the only time I check it, but I autocross quite a bit) and I always add too much. I'm worried it's doing this when I'm not looking, which is normally the case when I'm trying to look where I'm going. I've been trying to keep an eye on it, but it can be tough to push the car real hard when you're looking at the dash, and it seems it doesn't do if unless I push real hard. Know what I mean?

I am further worried by a tech response I saw a while back in the panorama where a guy wrote in saying he had popped his -6 at the glen. The first question the tech guy asked was if his car had the factory -6 tank. He didn't necessarily ask if the tank was a vellios, but he say that the factory -6 tank should be adequate for what he was doing.

My car has a pretty standard setup with an aluminum tank, no front cooler and -12 aeroquip lines. It's hooked up to a '69 2.0L motor that is mostly E spec. and I use a 7k rpm rev limiter, but shift at 6500 rpm.

I'd be interested to hear from you guys who are running on the track or autocross with the aluminum tank that fits in the stock location. Any pickup problems? Any tricks I should know?

Thanks for your help.

Kelly
Joe Bob
"I" heard it was baffle problem....
blabla914
Yeah Mike, that's what I heard too. I also heard the baffle problem was fixed pretty early on. Way before Vellios more or less moved out of the picture and Patrick moved in. Is this also what you heard.

Kelly
Joe Bob
Well....I've had contact with both of them. 25 years ago .....when I lived in Hermosa and George was in Gardena.....he was a fringe player....his stuff, worked...after a fashion. Needed lots of massaging to work right.....

As for patrick.....well that guy wouldn't get a shaved scheckel from me if he had the last rust free 914 on the planet.

But hey....I could be wrong.... cool_shades.gif
ArtechnikA
even the stock tank can have issues under extreme conditions, and the factory changed the internals on the 911 tank somewhen in the early 80's. the guys at Smart Raing can open, clean, rebaffle, and extend the stock tank for another quart or two.

in addition, you may want to go bigger on the line from the tank to the pressure pump, and make sure it has some internal support like an anti-collapse spring. that line can see a substantial vacuum.
blabla914
Rich,

I think you are right on. I should have relied on my own knowledge of dry sump setups. I am not currently running a spring in the suction line to the pressure pump. However, I've never talked to someone running my setup with stainless braid line who was. Maybe they have the same problem I do and don't realize it?

It would be tricky to go up to -16 on the entire suction side as my oil cooler has a -12 welded on to it. I knew I should have done a -16 on the cooler. I suppose I could put a -16 fitting and larger line from the tank to the oil cooler. I'll have to double check fitting availability to do that. Of course I'll run a spring too. It also looks like a -16 fitting out of the aluminum tank is really going to interfere with the quarter panel. Surely somebody out there has done a -16 fitting on an aluminum tank. What did you do?

Of course all this is for naught if this tank is just not up to what I want to do. Perhaps I should have gone with the larger front mounted oi tank like Joe has on his 914RS. The only thing I don't get about this is it makes the supply line awefully long. Do you run the anti-collapse spring the whole length? Conventional wisdom with dry sump setups is to mount the oil tank as close the engine as possible, but I see quite a few 911 and 914-6's with front oil tanks. Smart Racing even has a 911 front tank that fits with no cutting. Does anyone know what they recommend for suction line? Joe, your setup looks to be sorted, would you mind sharing what you used for a suction line?

Thanks for your help.

Kelly
brant
Kelley,

the common set up, is AN 16 only on the short 2.5 foot line that runs from the bottom of the tank to the motor-cooler input.

Big motors often run -16 all the way to the cooler and back to the tank, but that is not the line that is going to collapse.

the line from the motor to the cooler is push-pressured, by the pump.... and the return from the cooler to the tank is also working under the same push-pressure.

If you have a front mounted tank then yes that would need to be -16

but if you use a stock or a vellios alluminum (stock location) tank than the line in question is only going to be 3 foot in length.

brant
blabla914
Brant,

Thanks for the input. When I purchased my tank and lines -12 was suggested for all lines since it was a 2.0L motor. To go to -16 might get ugly since I have a -12 male fitting welded onto my oil cooler and space is of course limited. I am going to investigate my options tonight. If I can get a female -12 to male -16 45 deg fitting I'll be set. What do you suppose the chances of that are? I'm thinking not so good, but we'll see.

If someone could post the pipe thread size on a vellios aluminum tank it would save me the trouble of pulling the tank until I get the fittings and hose I need. I think it's 3/4" pipe thread, but if someone has a tank out and could verify that or knows for certain because they just did this, it'd be much appreciated.

Thanks,

Kelly
Series9
The RS has -16 supply and -12 on everything else. Yes, the supply is long (around 10'), but I've had no problems and the oil pressure is always 5 bar the instant the engine fires.
Series9
last:
Britain Smith
QUOTE (blabla914 @ Aug 8 2005, 06:59 AM)
Rich,

I think you are right on. I should have relied on my own knowledge of dry sump setups. I am not currently running a spring in the suction line to the pressure pump. However, I've never talked to someone running my setup with stainless braid line who was. Maybe they have the same problem I do and don't realize it?

It would be tricky to go up to -16 on the entire suction side as my oil cooler has a -12 welded on to it. I knew I should have done a -16 on the cooler. I suppose I could put a -16 fitting and larger line from the tank to the oil cooler. I'll have to double check fitting availability to do that. Of course I'll run a spring too. It also looks like a -16 fitting out of the aluminum tank is really going to interfere with the quarter panel. Surely somebody out there has done a -16 fitting on an aluminum tank. What did you do?

Of course all this is for naught if this tank is just not up to what I want to do. Perhaps I should have gone with the larger front mounted oi tank like Joe has on his 914RS. The only thing I don't get about this is it makes the supply line awefully long. Do you run the anti-collapse spring the whole length? Conventional wisdom with dry sump setups is to mount the oil tank as close the engine as possible, but I see quite a few 911 and 914-6's with front oil tanks. Smart Racing even has a 911 front tank that fits with no cutting. Does anyone know what they recommend for suction line? Joe, your setup looks to be sorted, would you mind sharing what you used for a suction line?

Thanks for your help.

Kelly

I have a fitting for an AN-16 line that has a reduction end on it to screw into a AN-12. I looked around in some catalogs for it, but wasn't able to locate it. I won't be needing it for my project and will probably sell it...shoot me a PM if you are interested.

-Britain
brant
I think the 12 line from your front aux. cooler is fine, and I wouldn't mess with that... especially for a 2.0

the short line from the bottom of the tank to the motor inlet (the motor cooler) is the one that is often bigger.

that may all be repetitious but I just wanted to make sure we were talking about the same thing.

---------------------------

But if your tank already has a smaller than 16 fitting welded onto it, I'm not sure if there is any reason to put an adapter on it. I'm no fluids expert, but I thought the restrictive neck of the smaller fitting would negate going to a bigger hose??? (somebody else correct me if I'm wrong)

one solution would be to actually weld a 16 fitting onto the tank...

or option #2 is to just leave it as a 12 I guess.

brant
blabla914
Brant,

You are correct on both counts.

We are both talking about the line from the tank to the inlet of the pressure side of the pump that is run through the tube connected to the bottom of the oil cooler. My car does not have a front mounted cooler, so I've only got two lines.

A -12 fitting at the bottom of the tank connected to a -16 line that's only 2 or 3 feet long would make very little if any difference.

However, that's not my situation. I have an aluminum tank with NPT's in it. Into the NPT's there are NPT to an adapters. Currently I have an NPT of unknown size into a -12 AN fitting running though -12 line to a -12 male fitting welded to the oil cooler. That's the engine mounted oil cooler. That's were things potentially get ugly. I understand guys running 3.0L motors or bigger run an NPT to -16 adapter in my tank to -16 line. The problem is I need to hook the -16 line to the -12 fitting on the engine oil cooler.

This may help because the restriction is now much closer to the pump. I stress may since it is still a very short line. Since the line may be collapsing I could now run the anti-collapse springy thingy inside the larger line. I'm going to try the anti-collapse springy thingy first and see if that does the job.

Kelly
blabla914
Joe,

You must have replied while I was typing.

So you don't run any anti-collapsing springy thingy in your -16 suction line?

Kelly
Series9
QUOTE (blabla914 @ Aug 8 2005, 03:50 PM)
Joe,

You must have replied while I was typing.

So you don't run any anti-collapsing springy thingy in your -16 suction line?

Kelly

No.
Luke M
Hey, Kelly

I'm going to run a Patrick Motorsports 914-6 oil tank.
This is what I got, -16/ 1'' NPT at the tank to -16/45 , 3' of -16 hose, -16/45 to engine cooler(-16). Hope this helps you out.
Luke
ArtechnikA
hijacked.gif
for you guys running aftermarket (or OEM, for that matter...) where do you go for the filter console? i want to update the one on my '71 tank to the '72+ version before i install the 2,7.
blabla914
Rich,

The aluminum tank has the console built in. You just screw the oil filter (oc54) right on. In my mind, that's one of the big advantages of the aluminum tank.

Luke,

Thanks for the info. That's what I have too, but my 1" NPT connectors are -12.

Kelly
ArtechnikA
QUOTE (blabla914 @ Aug 8 2005, 07:57 PM)
The aluminum tank has the console built in. You just screw the oil filter (oc54) right on....

i've lost track -- izzat the pre-'72 or the '72+ filter?

ok - you non-aluminum guys reading this thread - anybody got a line on a '72+ filter console?

(thanks...)
blabla914
Joe,

thanks for the reply. I know it's been said like a million times, but that car is really, really slick. You and brant should start a detailing business.

Brant,

I went through your build thread last night and biking water bottles and cages as catch cans is pure genius. I'm going to use that at some point.

Rich,

You know I have to look that filter up everytime I order one. I believe it is 72+ and 930, but I'll check tonight.

thanks for help guys.

Kelly
brant
Thanks Kelly,

also I wanted to say.
that with the stainless steel wrapped line... I don't think collapsing is a big issue. That stuff is strong and rigid.

I don't run any spring in the line

brant
ArtechnikA
delamination of the inner liner may be rare but IMO it's easy enough to guard against. but like a lot of things on these cars, there's plenty of room for individual interpretation and implementation.

Inlet line spring
brant
good point Rich.
never too safe.

but we left a lot of things out for weight.. including the thermostat and nearly anything that didn't make it faster.
only way to get a metal car down to 1850 with an aluminum -6 case.

but still probably a good safety Idea.
brant
ArtechnikA
QUOTE (brant @ Aug 9 2005, 10:57 AM)
but we left a lot of things out for weight..

i can't fault a carefully considered engineering decision, even if i would make a different decision.

i only bring it up in threads like this because it's something you *won't* see discussed in books like Pelican Wayne's or even Anderson's. i want to make people aware of the issues and alternatives. then - it's up to you.
blabla914
I have some info for you guys, or as the Dude said "new s**t has come to light, man"

Luke,

Thanks for posting that pict of your tank and the fitting. However, since that fitting appears to measure 1" at the tapered end means it is 3/4" NPT, not 1". Carrol Smith reminded me that NPT refers to the INSIDE diameter of the piece of pipe that accepts the thread.

Some interesting dimensions:
-12AN ID is 0.69"
The ID of the S-line from my engine when it was in a 911 is .743".
-12 is a little small, but not terrible.
Here's where things get ugly. The ID of a -12AN fitting is only 0.583"
The ID of the tube on the bottom of the oil cooler where it meets the case is 0.707"

I did a little searching on some other forums, most notably an off road racing forum where they seem to all be running dry sump setups. An undersize supply line was listed one of the reasons people lose oil pressure at high revs. Another was not using an anti-collapse spring in the supply line.

Seeing that I've only noticed a problem after I started running 30 mm chokes and a 7k rev limiter (stock is 7100+/- 100) I'm thinking starvation at high revs is my problem. I'm glad I sorted this car at autocrosses before going to the track. Seems to me sustained high revs at the track would have had a rod sticking out of the block quick.

Smart Racing Products recommends -16 supply AND the spring for rear mounted tanks and -20 also with the spring for front mounted tanks. These guys seem to drive their cars like I drive mine. When it runs.

Smart also makes a big deal out of the fact that their anti collapse is flat instead of round. I don't know if this is really as big a deal as they do, but it's about the same price so what the heck.

Bottom line, I'm going to switch the supply line to -16AN and run a smart anti collapse. I also found bakerprecision.com which was the only place I could find an aluminum weld on male -16AN fitting.

Joe,

I know your setup has quite a few miles on it and some track time, but if I were you I might consider atleast getting an anti-collapse and maybe switching the supply to -20. I know it's expensive, but it's cheap compared to a motor.

Rich,

Thanks for posting the spring. Not easy to find them for sale though. Oh and an OC54 is definately 72+.

Kelly

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