Oil cooling in a T4

I'm not a T4 guy, but I like how you think and agree completely. It's amazing to me that when the Sainted German Engineers "fixed" the T1 with the T4, they left the stupidest part of the original design largely unchanged.

The ACVW oiling system (both T1 and T4) is a Rube Goldberg mess.

YUP! I pondered that when I changed to my dry sump system on my type1. I have a JayCee oil filter mount with bypass(at 80 psi goes back to the tank), as my Autocraft pump(and Stan's Bugpack) both have no provision for pressure relief.

As Davros99 says, there is no need for internal pressure relief if you have that taken care of externally. As Davros99 also has with the pump cover bypass. I had that setup originally, a Berg.

If I ever split the case, removing the factory bypass will be on my agenda.

Rube Goldberg indeed.

I was surprised when my local shop was bagging on T4s.  I was under the impression that they were great!  I'm sure nothing is that simple.  The mechs were saying that VW basically went back toward the T1 design with its Vanagon and other waterpumpers.  Is that so?

Sorry to hijack the thread.  Carry on...

I had a '72 VW bus with the 1700 cc T4 and dual Solex carbs (in '75) - like 70 hp.  Not much improvement over the '71s T1's 55 hp.  The 2L T4 was used later - FI was added in '75 (vs carbs). In '83 the T4 was dropped and a T1-like engine with water jackets was used - the wasserboxer.  It was pancake flat so looked likea  T4.  So shop is correct.

My bus gobbled a valve and when I took it apart, in addition to broken valve and bashed piston and head, I found cracked main bearing seats (It had been apart before I bought it) so I replaced it with a Porsche 914 1.8L I had.  Not a bad vehicle to drive (with air shocks that lowered it a bit).

My plan to block the functioning oil cooler bypass pressure valve, make it stay closed and therefore keep the oil path through the cooler circuit, is to block the bypass valve spring with an appropriately sized rod which will prevent the valve plunger from moving down under pressure, opening the cooler circuit bypass passage.  Thinking about the best way to do it as the exact rod length would be difficult to determine. The spring defaults to the proper length, a rod doesn’t. A stub rod could shim the spring compressed stopping its working travel and hold the plunger closed.  The spring length may need to cut down to ease installation.
By the way I still need a berg pressure relief cover.  anyone have one ?  GB is out of stock, and no idea when they will have more. Hmmm.

@Teammccalla posted:

I was surprised when my local shop was bagging on T4s.  I was under the impression that they were great!  I'm sure nothing is that simple.  The mechs were saying that VW basically went back toward the T1 design with its Vanagon and other waterpumpers.  Is that so?

Sorry to hijack the thread.  Carry on...

I personally don't have any experience with type4s. But I do have some with the Wasserboxer from the Vanagon. It was 76 stroke x 94 cylinders, for 2109cc. A whopping 90hp, which is sad. The Subaru 2.2 which many people have retrofitted had 130hp bone stock, albeit with 4 valve heads and overhead cams. The perfect swap is the EJ25 at 165hp. I always wanted to install the EJ33, a 230hp flat six from the SVX.

Back to the subject at hand. You take a type1 case, and add water-jacketed cylinders and watercooled heads. And a water pump too. Same type1 oil system, but it had a real screw-on oil filter. The water jackets were part of the case. Iron cylinder liners set inside. Some people had trouble, but I never had water leaks on mine.

The Digifant injection worked fine, though. No OBD.

VW did go with a 5 bolt crank flange a la type4, so there's that. The case also had an actual oil seal on the pulley end too. They may have had a bigger type4 style center main bearing, I don't remember.

So in the end the Wasserboxer was an amalgam of type1, 4 and newer stuff. It wasn't bad, but it didn't have power. 90hp pushing a 3600 pound Westy is still sad. Even for 1991, the last year of production.

Sorry for all that meandering. The Wasserboxer did go back to a 26mm oil pump(stock since the mid-60s), basically the exact same type1 Rube Goldberg setup as original, but with an actual filter.

Depending the level of preparation of your engine and the cooling system you're using.

I have experience with the Porsche shroud system + external heat exchanger + Racimex bypass, and 2nd mount with T1 shroud + original T4 heat exchanger

Both system are working well.

@Davros99, not Berg, but I have one of these in non pressure relief, and it is quality.  I didn’t need the pressure relief as I have that with the Jaycee pressure relief oil filter mount, same as Danny.

https://www.thesamba.com/vw/cl...etail.php?id=2484955

I'm dry-sumped, but if I was running a wet sump in a Speedster or Spyder, I'd do the following:

• I'd use a thin-line 1-1/2 qt. sump
• I'd full-flow it and get a blueprinted oil pump. I'm not nearly as concerned about the size of the pump being too big (as some folks are) because I take care of excess oil pressure. I'm always much more concerned about being too small than too big.
• I'd run a Jaycee pressure relief oil stand. This has a valve that opens at 80 psi and bypasses excess oil pressure back to the sump. This is why a 30 mm pump is fine.
• I'd pipe an Accusump into the filter stand. An Accusump is an oil vessel with a bladder like a well pressure tank. It holds a couple of quarts of oil at normal running pressure, and has a valve that opens when oil pressure drops below a certain point (20 psi is where I have mine). This vessel keeps the galleys pressurized if the pickup is exposed to air. It's also great for pre-lube. Why these are not used more remains a mystery to me.
• I'd put a Mocal sandwich bypass thermostat on the filter base and pipe to a Setrab oil cooler with a fan (also on a thermostat).
• I'd probably remove the doghouse cooler and run an early 36 hp-style shroud. I'd try to find a shroud that would accommodate the wider late fan (which would be welded/balanced). The little stand cooler is ridiculous.
• I'd disable both of the stupid bypass pistons.

That's what I'd do. Your mileage may vary.

Some people convert the Wasserboxer to air-cooled and discussed on ShopTalkForums.   

Yes, they do cut off the water jackets. I think people who do that refer to them as an "Oxy-boxer" or some such oxymoron.

For the record, I think they're pretty cool but seems like a lot of work to get a 5 bolt crank flange, aluminum case, and a front oil seal. You can get an aluminum case and a sand seal easy enough. Is the 5 bolt crank/flywheel and on-board screw-on filter really that necessary? They used stock 1600 Beetle rods for Pete's sake!

https://www.sub5zero.com/great...deo/#google_vignette

@James550 I like what you're doing there. I also have an external-only cooler(96 plate) and a 911 fan with custom(or is it bespoke today?) 'glass shroud.

Yesterday it was 67 to 70 degrees, and I got the cobwebs out of the car. I put the Vred tires back on, checked the oil and took a good long ride. Oil temp reached 180 barely, the fan never came on. I couldn't get it hot enough to trip the switch(190 degres).

I'll change the oil once it gets hot enough to get the engine truly warm.

The car seems REALLY fast, that first ride of the year.

Oxy-boxer/Type-5 (et al) were a "solution" before the advent of Auto Linea aluminum bubble-top cases 20 years ago. They have all the things Danny lists, which are now all available for about 1/20 the work and money from CBP/EMPI/etc.

They were the cat's pajamas for about 10 minutes. Now, the TF1 (like @LI-Rick has) is the way to fly for big-dollar, big performance builds not concerned with weight.

Rocky Jennings was one of the guys to pioneer the oxyboxer.  I thought about trying this myself, but the juice just isn't worth the squeeze.  If you have to pay someone to do all the machining, I think you would be into the case for over $1K, and you have to supply the case.  A bubble top case would likely be cheaper and much easier.  

I don't even know the availability of a big stroke crank for a Type 5.  I know some have done welded strokers, but the cranks are cross drilled so max stroke is 82mm.  If you really think you need a flanged crank, they are readily available in Type 1.  Hint: Unless you are drag racing on slicks, no one needs a flanged crank.

The TF-1 case really is the cat's meow, and currently not a huge premium over a bubble top case from CB.  I just dropped an 86 stroke into one, and it has all kinds of cam clearance due to the .100" dropped cam.  The machining is really nice, they are through bolted instead of using studs, the lifter bores are huge and they have jack screws to separate the case halves, which is not easy on a case with 6 shuffle pins.  When you are checking bearings in the case is when you really appreciate this feature.

Say more, Rick.

I've never had one of these engines apart, but I figure it's only a matter of time, and I need to be able to picture in my head what's being described.

You say "the lifter bores are huge" and all I can think is "custom lifters that are bigger" which...why would that be a thing?

"and they have jack screws to separate the case halves," which...how? The case halves have jack screws built-in? Where? How?

@edsnova,  here are a couple of pictures.  It is currently together in mockup stage, and I am fitting tin right now.  If you want to see something else, let me know and I'll grab a picture when I tear it down for final assembly.

Here is the case in the dishwasher after deburring.

Look at the size of the lifter bores.  No chance of breaking one.  You can also see the 6 shuffle pins, and notice the lack of case studs on the mains.  These use through bolts that get torqued to 50 ft-lb, as opposed to stock @ 18 or Berg style @ 30.

They use standard lifters.

Back of the case is cast solid, all of the oil galleries are tapped, and is drilled for the Hoover mod, if you should choose to use it.

The only thing I did to the case was tap for a plug in the oil feed. I was surprised to see this wasn't done.  I know it is not 100% necessary, but it is easy insurance.

Here is one of the 4 jack screws.  There is one in each corner.  Turn them in a turn at a time and they push the case apart.  They are captured, and can't fall out.  If I ever use a regular aluminum case, I would add these.

There are some options available when you order one of these, 94mm or 101.6 bore, you can eliminate the oil control system, cut for flanged crank, and sand seal.

Wow! Thanks, Rick. That's the stuff!

Here is the company that I think started  the aircooled waterboxer,

https://limflug.de/en/products/engines-56kw-75kw.php

They are a little bit north of Frankfurt , Germany

@imperial posted:

Here is the company that I think started  the aircooled waterboxer,

https://limflug.de/en/products/engines-56kw-75kw.php

They are a little bit north of Frankfurt , Germany

Any idea when they started doing their conversions?

Ummmm I think I went there in the 90s , I  was told about the place by some Kafer Cup racers .

@imperial posted:

Ummmm I think I went there in the 90s , I  was told about the place by some Kafer Cup racers .

Intertesting.  They don't give any history on their site.  I know drag guys were running Type 5 back in the 1990's also.