A local friend is one of the best metal fab guys in the country and we've been kicking around this idea. Is there a big enough market for another, better, oil tank?
I think we could offer it a bit cheaper than what's out there now. Could I get some feedback regarding what would be the ultimate 914-6 oil tank....size, material, construction, features, baffling, etc?

IMHO, it could be just like the oem tank, if it's cheaper... that will suffice most conversion needs..

I think cost is the biggest downfall... $500 for a 30-year old oil tank?!

which is why if I get a /6 conversion, I'll buy one that is complete or 90% complete... the little parts prices just kill me.

QUOTE (goose2 @ Aug 9 2005, 11:25 AM)

what would be the ultimate 914-6 oil tank....size, material, construction, features, baffling, etc?

better baffling, more capacity, port sizes suitable for a 3,6.
anticorrosion coating - powdercoated mild steel would be fine IMO.
maybe offer aluminum or stainless.

a good replacement tank should be suitable for stock cars that require replacement for some reason (rust, impact damage, whatever...)

QUOTE

better baffling, more capacity, port sizes suitable for a 3,6.

Has anyone ever seen the inside of one? I'm wondering how the original baffles are configured and how they could be improved. Pics would be great...or better yet does anyone have a trashed one to cut up? And Rich...can you elaborate on the port sizes?
Thanks

QUOTE (goose2 @ Aug 9 2005, 11:52 AM)

Has anyone ever seen the inside of one? I'm wondering how the original baffles are configured and how they could be improved. ...can you elaborate on the port sizes? Thanks

lots of people - but not me. SmartRacing has a service in which they open, clean, rebaffle, and extend the tank. it's a couple-3 hundred bucks plus the shipping.

there have to be dead tanks out there. my *guess* is that it is essentially similar to a pre-'72 911 tank, in mirror image.

i donno what line sizes the 3,6 guys are using -- a quick look at the lines or an OEM 3,6 Carrera tank would give you a clue. my guess is AN-20. i think AN-16 is fine through 3,0 -- probably a tossup on 3,2's.

The most inexpensive solution is to pick up a "Coleman" catalog. They cater to American V-8 Racecars/ NASCAR. $300 will get you a 5 gallon capacity oil tank and for a couple hundred more, all the best quality fittings and lines. You give up your front trunk completely, but you still have the choice of paying Porsche $1200/1500 for all "stock" parts for less capacity (albeit you keep the trunk)

Peterson oil tank for around $300:

Someplace I had a book mark to a cutaway of the oil tank. I've looked for it in the past when the subject came up. But I can't find it. Biggest worry when it comes to the construction is the baffling. If you can't knock the air out of the oil the motor will self distruct. At least that's what the sinics have posted in the past. It can't be rocket science....

The stock baffling is not too intricate.
keep searching .. here and on pelican
I've seen pictures, and I've also seen computer drawings

There is a tiny bit of plumbing inside of a stock tank.
Enough that the oil is forced through the oil flter at some point. I'm trying to remember the order of events, but I believe that the oil is forced into the tank under pressure from the motor/pump. I believe it enters the plumbing and then the filter, and then spills out through the screen. Finally it puddles into the bottom where it then gravity siphons into the motor return line. The motor return line has a little suction helping also.

the baffling is really a anti-foam piece of screening. The oil is forced to run through a piece of screen to reduce the frothing of the oil.

I would be interested in buying a tank.
here is what I would need in one in order of importance:

1) stock location mounting ability.
2) 300-400ish dollar price range
3) stock or better levels of baffling.
4) provision for an oil filter in the stock location would be really nice!

your right its really not rocket science.
your friend will need to be careful that he does not contaminate the inside of the tank with any welding slag/extra welding wire, or anything that would blow a motor up.

brant

construction of "an" oil tank is shown in one of Carroll Smith's books (the first, "Prepare To Win" i think). there's also construction detail in Ron Fornier's "Metalcrafter's Handbook."

tanks need to be tall. they serve to de-aerate the oil and make sure it stays at the bottom, near the pickup, for which flanged labrythine baffles are used. too many baffles and the oil won't get to the pickup fast enough (starvation, backpressure in the scavenge circuit...). too few, and the oil sloshes away from the pickup (oil starvation, excessive pukage...).

they're not rocket science but neither are they trivial. they have to be strong enough, structurally, to hold 10-12 quarts of 250F oil without leaking or cracking. you need to be very confident of your welding. if a fitting breaks, the owner will probably lose the engine, and if it spills on the rear tires at speed, possibly the vehicle.

i'd consider an alternative design that fits in the stock space -- after someone's done a year or two of track testing...

Thanks (Tanks?) for all the input guys. As with most projects, there's more here than meets the eye. I've got the Carroll Smith book, I'll check that out...and search for some images too. I also have an early 911 tank that leaks....I can cut it up and see how it works. Good point about leakage or weld failure...very baaad mojo.

I actually have Porsche original factory drawings of the tank. They're a little dirty, but very legible. I should try to finbd out If I can have them digitized and post them.
I'll see and let eveybody know.
Michel Richard

Why re-invent the re-invent???? Reproduction tanks are available in aluminum with about a quart and a half more capacity than the factory tanks. They use all the factory mounting hardware.

In the scope of a six conversion a couple hundred extra more for a tank that fits and functions better than a tank for a race car, is a spit on the griddle.

IE, if you are worried about spending $500 or so on a oil tank forget about the six converison!

Just my opinion though, I've been down the road with this project and doubt if you'll get better results for any less effort or money.

QUOTE

Why re-invent the re-invent????

Well, if it can be done better...or cheaper just as well, why not? I'll admit though, after due consideration of all the requirements, not to mention the liabilities, the prices on the aftermarket tanks are looking better. I think I'll shelve this idea for now and get on with more urgent things...like putting my car together. Thanks for the input everyone. Maybe I'll get back to this when my plate is not so full.

5 gallons?

I have beer kegs.


M