and now a few words about sumps....

[SGB]

Well I want a deep sump. Pelican has two. The well known tuna can, and the "914 deep sump". Anyone have experience with the later? I've read that the tuna can needs machining somehow. Where? How does it not fit? I really want the extra capacity (I figure its gotta help cooling) more than cornering/ oil starving concearns. Please somebody tell me about these.... Jason?

[Acox914]

i just got a tuna can from a member. it hangs WAY below the engine bar! not good!. my car is very low, and if i tagged a speedbump...can you say new case?

the choice is yours

[synthesis]

tuna can is great for auto-x, street car and some race cars run it succesfully. However, most TIV race cars I have seen run the deep sump or a dry sump.

The tuna is cheap and easy to install so try it out and see if it works for you, if not, go deep.

Sump does hang real low but I have gone off track, spun, etc with mine in place and haven't had a problem, YET.

[ken180]

The "tune can" does not fit ALL motors. The only way to know is to try it.

Ken

[SGB]

I think I rethink the whole thing.....

[Dave at Pelican Parts]

Aaron, I am very surprised to hear that the Tuna Can hangs down that low!

And Ken, AFAIK the Tuna Can does fit all 914 engines. When it's the right parts. (See below.)

My experience:
The Tuna Can comes down to just above the level of the bottom of the motor mount bar. You can hit the bar and bend it back slightly without ever touching the can. (Guess how I know that? Reminder To Self--new motor mount bolts!)

The deep sump is much deeper. It holds more oil, but evidently hangs down noticeably below the level of the motor mount bar. It clamps onto the edges of the center sump hole.

Evidently in rear-engine'd applications (e.g., Bugs, Buses and 912s) the Tuna Can is very exposed to damage. That is not really the case in a 914 IMHO.

Weltmeister had one (or more!) bad batches of Tuna Cans. The oil pickup extension tube is too long in those cases. I do not recall the exact dimensions, but the long tube will not allow the top of the can to mate up with the bottom of the engine. We have yelled at them about it on more than one occasion. I'm not sure if the ones currently in the supply line have been corrected or not. (!!!) I do hope someone can measure a "good" one for us; but mine is tucked away inside my engine where I can't reasonably get to it.

You can make a too-long tube useable by machining the excess length off the bottom. Again, I don't know the correct length nor exactly how much needs to come off, but it is something near 1/8"-1/4". Or thereabouts.

--DD

[SGB]

thanks for the info Dave..

[John Kelly]

In a rear engine application, I have broken two Berg sumps, once while going up a very steep hill with hard landings (stupid) the other time I hit a piece of concrete on the freeway. Both times the sump was the only thing damaged. In looking at the tuna can on my 914, I think I will make a sump guard of some sort for it. Maybe it should have been made out of something a little less sturdy so it would break instead of damaging the case?

John www.ghiaspecialties.com

[synthesis]

Here's a series from my sump install.

[SGB]

Great picture series. Thanks. That is pretty big. I can see how it would certainly provide extra capacity.

[BigD9146gt]

Scott, if your worried about losing pressure during cornering, i would look into an oil pressure accumulator. they are pricy, but its the best way to keep pressure built up. Then for extra cooling, an extra oil cooler would be choice. The big sump that synthesis shows is nice, but does hold heat closer than an external cooler would.

[Dave at Pelican Parts]

Cooling and capacity are two separate, almost unrelated, issues.

If you want to keep the light on in the corners, and you don't have long high-G corners, simply overfilling the engine by a half-quart may do it. If you have longish moderately-high-G corners (i.e., a long sweeper with aggressive street tires on the car), the Tuna Can works just fine. It now takes about 3 1/2 on-ramps in a row to get the oil light to come on in my car.

If you are running race tires (slicks or "competition" type tires) and running on courses with sweeping turns, the Tuna Can may not be enough for you. (It is for me, so far, but I am still running on hard-compound street tires.)

I would not recommend the deep sump pictured above--it just hangs down too darn low!!

The "Accusump" pressure accumulator can/should work well for maintaining oil pressure. However, there can be problems with the install. There are one or two people over on the Shoptalk Forums who have lost engines to Accusumps that (presumably) were improperly installed.

Cooling is a separate issue. The deep sump and the Tuna Can both do provide very slightly more surface area down in the sump, which can help radiate a tiny bit more heat than stock. I doubt it's enough to measure, though. An external cooler is the best way to get rid of unwanted heat in your oil. Where to mount and how to plumb the cooler is always an interesting question...

--DD

[BigD9146gt]

Originally posted by Dave at Pelican Parts
Cooling and capacity are two separate, almost unrelated, issues.
--DD

Dave, in what way do you mean?

In theory i abosolutly agree with you. But lets take a look at a close cousin. The 911 holds at least 9 Quarts. The more oil you have, the longer it takes to heat up. The 911 engine holds almost 3 quarts, the rest in the tank, lines, and extra cooler if one is installed (13Quarts for the SC setup).

If one has a cooling problem, i agree throwing more oil at it will only solve the problem for a short period of time. But adding an oil cooler helps.... but then you add more capacity to fill all of the extra cooling equipment.

Turning the TIV engine oil system into a dry sump system is a VERY good way to increase engine longevity and keep it running cooler. If it wasn't a better system for the air cooled setups, Porsche would not have done it for the past 30+ years. Granted thats not the only reason they went with the drysump, but its a major one. By adding the dry sump you are increasing the surface area by which the oil can expend heat. Plus, the oil tank searves as a nice deap sump. All of the oil in the tank must be drained to make the oil pressure drop, and by that time, more oil is now in the catch and rising toward the pickup sending it back to the tank filling it up.

[Dave at Pelican Parts]

What I mean by them being "almost unrelated" is exactly what you say in your third paragraph. The key, in my eye at least, is that throwing more capacity at an oil system because you are running hot is a band-aid at best. And also adding a cooler to an oil system that is experiencing a lack of pressure is not helpful, and can actually exacerbate the problem.

Dry-sumping is good, but is tough to do with the stock cooling system. It is also expensive, and requires quite a bit of work no matter what.

Other benefits to dry-sumping: Oil is scavenged out of the case, so you do not get splashing and the oil vapor/etc. inside the crankcase is vastly reduced. Less pumping losses due to that. You can eliminate most of the sump, bringing the CG of the engine even lower. But primarily I think engines are dry-sumped to make sure they've got oil pressure no matter what goes on.

I would bet that the cooling benefits of a dry-sump tank would be little enough that it would be difficult to measure in the temperature of the engine oil. Adding a cooler, however...

--DD

[jhadler]

Deep sump vs. Tuna Can....

The only circumstance I can see the deep sump being worth while over the tuna can is if you're raod racing the car and don't feel like plumbing in an accusump.

The two issues about extra sump extensions that I see. Capacity (to prevent oil starvation), and Cooling.

Extra cooling is accomplishied WAAAY more effectively by adding an external oil cooler. Oh and ta-da, it also increases the capactity of the oil system (although not the way desired as mentioned above). Both the tune can and the deep sump will play negligable roles in cooling your oil down. Yes, they have more surface area, but in order for that to be effective, you need said surface area in the flow of cool air. Not stuck under the car between the exhaust headers. An oil cooler, even hanging off the engine lid or above the transmission, will reduce your oil temps way more than any kind of sump extension.

Oil starvation prevention. The tuna can, IMHO, is extreemly effective at reducing the possibility of oil starvation. I've autoxed, and tracked the car with no starvation issues (knock wood...) with just the tuna can and a little extra oil depth in the sump. The deep sump, if propoerly equipped, can give you a little more insurance, but for the cost of the deep sump, I'd just go out and get an accusump. The deep sump hangs lower than the tuna can, and not secured to the motor any more effectively than the tuna can. With it's increased length, width and depth, it's just asking to collide with something. An accusump doesn't cost much more than the deep sump and will totally eliminate the worry of oil starvation. Okay, so some have had problems, that can be said for ANY modification to a motor. All in all, the accusump is a simple device, and far less likley to cause harm to your motor (propoerly installed) than a deep sump might.

Oh, and the comparison to the 911? The 911 is a dry sumped motor. If you really want the security of oil protection and increased oil volume, dry sump the motor. Don't just extend the existing sump (asking to be damaged), bite the bullet and go the dry sump route.

just my $0.02...

-Josh2

P.S. Hey Dave, the motor is getting assembled this winter! We'll see what spring brings...

[BigD9146gt]

Originally posted by jhadler

Oh, and the comparison to the 911? The 911 is a dry sumped motor. If you really want the security of oil protection and increased oil volume, dry sump the motor. Don't just extend the existing sump (asking to be damaged), bite the bullet and go the dry sump route.

I didn't think i said to extend the sump and do a dry sump. I was just trying to use a better system as a reference in what should ulitmatly be done to prevent oil starvation and higher tempuratures.

[jhadler]

Originally posted by BigD9146gt
I didn't think i said to extend the sump and do a dry sump. I was just trying to use a better system as a reference in what should ulitmatly be done to prevent oil starvation and higher tempuratures.

Yeah, but it's apples and oranges when comparing the 911 oiling system to the Type IV. And to make a Type IV as efficient (with respect to oil handling) as the 911, you will need to make it a dry sump motor anyway. The Type IV is a great motor, for what it is. But it's not exactly the peak of sophisticated engineering...

-Josh2

[BigD9146gt]

Originally posted by jhadler
Yeah, but it's apples and oranges when comparing the 911 oiling system to the Type IV

-Josh2

I know what you mean, but I don't fully agree. Both use oil to cool the motor (and air to cool the oil along with the motor). Its just one stores most of its oil away from the engine. I can also agree that the 911 pump is in a sence two pumps being a scavenge pump and a primery pump, where as the type 4 is a lonely single doing all the work. However, its not that hard to add a tank to the system which would help aid a hindering system.... A lot more work? Yes.

I guess it all comes down to the end goal. Dave really likes his tuna can. It sounds like for the money, its one of the better systems out there for oil starvation. A buddy of mine who was racing the POC really liked (more like needed) the accusump for being out on the track. I've heard of the dry sump approach in the type 4's, I think John Rogers did it before he went to the 911 engine. Maybe its more money than its worth. By the time most 914-4 race guys get the max out of what they can do with the type 4 engine, they have spend more money than a 6 conversion, so they convert. Whats the right answer?: Whats your goal?

[Dave at Pelican Parts]

There is no right answer, of course! What's right for you depends on your own goals and your own particular circumstances.

A true bolt-on dry-sump system that works well on an otherwise stock motor would be pretty nifty! I'm not sure that it would actually work, though, without messing around with the way the oil is routed inside the engine. (E.g., oil cooler bypass, oil filter bypass, etc.) But for most of us, I think the Tuna Can works well enough. And it's certainly the cheaper solution.

--DD

[BigD9146gt]

Dave, it wouldn't be all that hard to make one up. The only tricky part would be the scavenge pump to the tank. besides that, feeding into the engine oil pump would be easy... just take out the aluminum plug thats on the lower right side of the case as your facing the oil pump, plug up the inner part of that hole that used to go to the old oil pickup, and weld on a fitting to now accept an oil line from a dry sump tank. Then install a pickup where the old one was.

It wouldn't be any more work than fixing the oil pickup mount when it gets stripped from over torquing the sump plate nut.