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dry sumping WBX/oxy boxer
1303Steve - June 22nd, 2018 at 06:43 PM


Long story short building a 2332 oxy boxer.

I've been unable to find very much information on dry sumping an WBX/oxy boxer.

Hopefully some experts will chime in.

Because the WBX/oxy boxer doesn't have sump plate like Type 1 or Type 4 motors I thought about using a Moroso pick up in the case and moving it closer to rear of the engine (crank pulley end) and having the oil scavenge exit the case where the WBX and Type 3 &4 style oil neck attaches and of course getting rid of the stock oil pickup.

The next issue is that the dry sump oil pumps hang out the back a long way which gets in the way of the exhaust, so Im thing about going belt drive. A friend of mine built a cool 3 stage pump and is not using it anymore, he can also convert it to run a drive belt.


HappyDaze - June 23rd, 2018 at 08:55 AM

Steve, just a word of warning about a possible 'side-affect'...loss of oil cooling.

You may remember the Autocraft dry sump set-up on my sports sedan. It did a great job of moving the oil from the engine, and enabled more oil capacity and better cooling. Trouble was the oil no longer 'sloshed about' in the crankcase, therefore causing it to run very hot, despite the cooler oil. Something to consider?

Cheers, Greg

1303Steve - June 23rd, 2018 at 03:03 PM

Thanks Greg, if the pick up is a little high in sump that might leave enough oil to slosh about. the case is factory aluminium so it should take a bit of heat OK.

Did your sports sedan setup use one of the Autocraft sump plates?

HappyDaze - June 23rd, 2018 at 04:45 PM

The aluminium case holds it's strength better at high temps, for sure.

Because of the ride height, anything hanging too low was a concern. Used internal scavenge.

Sick68VW - July 15th, 2018 at 08:52 AM

Hey steve on my car instead of a dry sump i went for a Oil Accumulator which so far has very good results. Theres a heap of write ups on them..

1303Steve - July 15th, 2018 at 07:59 PM

Hi Steve

My son and I are both using Canton Accusumps on our cars, mine on my Subaru motor and David on his RB30 powered Nissan Cefiro drift car.

They work great and give the added benefit of pre oiling before starting, we may even fit a small Accusump to this motor for pre oiling.

Fitting a dry sump has other benefits and I always like to see what big brother Porsche did, they fitted a dry sump to 6 cylinder 911s.


dangerous - July 17th, 2018 at 08:34 AM

The Shadek dry sump pump sold by CB is quite nice and my customers have liked them.
They only have 21 pressure gears and 26 scavenge but that should be enough
unless you have large oil clearances.

I use the Autocraft on my own, and drilled for internal scavenge,
but the tolerances are not as tight as I would like on the gear teeth,
and so the 1.25" pressure gears are needed, even though normally a 26 pressure gear is more than enough, for any engine.

1303Steve - July 17th, 2018 at 09:44 AM

Thanks Dave, so the CB pump is worth using, it makes life a lot easier with exhaust etc.

While researching WBX oiling systems I came across a strange thing that VW did with these motors.

If you look at the photo of WBX case that posted above, below the cam gear bearing nearest the oil pump there is a rectangular passage.

The oil pressure relief drains into that passage and the oil pick passes has a hole in it where it passes through the rectangular passage. WBXs are plagued with low oil pressure issues, this could be a cause

dangerous - July 18th, 2018 at 01:09 PM

Yes, that WBX bypass port is the first I saw, and I think it exists on some(all?) type 4s too.
I felt it was a problem too, and plugged it on my Oxy Boxer, back I the late 1990s,
and changed the 6 studs to some bigger ones, because I was worried the case was moving and drawing in air.

You may need to provide another method of pressure control, externally....if you block it.

Mine never lacked pressure (that I saw), but every bearing was measured, and crankshaft ground to suit.
Other than actual faults (with pumps and relief valves), pressure is governed by oil clearance, viscosity and pump size.

You might be correct in saying this port is a problem,
especially on a worn engine where the case halves' faces are no longer flat.....or loose.

dangerous - July 18th, 2018 at 01:13 PM

With the CB pump, (and any pump for that matter)
its worth measuring the body and make sure its tight in the case.

If not, a simple O-ring groove can be cut into the pump body (like Berg does) to prevent air leakage.

1303Steve - July 19th, 2018 at 09:47 AM

Hi Dave

I would still use the factory oil pressure relief but I would allow it to dump into the main case area by drilling a few holes in the rectangular passage. The oil pickup is also in bad location, I would move it towards the cam gear and lower it a lot.

I could see the port being a problem if insufficient sealant was used around rectangular passage when assembling the case.


1303Steve - August 30th, 2019 at 02:56 PM


We're going with a Subarugears transmission with my sons car. The conversion flywheel came the other day to link a WBX crank to a Subaru trans.

1303Steve - September 19th, 2019 at 06:17 PM


Just had most of the motor and crown wheel and pinion cryogenically treated at MT&CE in Silverdale.

Putting it together soon

hulbyw - September 19th, 2019 at 10:27 PM

Glad to hear of someone else that uses cryogenics. Some folks don't place much store in it but I reckon it is worth trying given that it is not all that expensive. I had the crown wheel and pinion done in my previous Prado when fitting the locker, and the crankcase, cam and followers in my Beetle engine (which I have sold on before assembling and using). You have reminded me that I need to get the case, crank, cam and followers done on my new engine before assembly

1303Steve - September 20th, 2019 at 11:50 AM

Thanks, its the first time for me. We're also getting some parts HSPF treated as well

1303Steve - September 4th, 2020 at 01:54 PM


We converted my sons bug to Nissan pattern 114.3 so we did some test fitting the other day, going 17 on the front and 18 on the rear

Bizarre - September 6th, 2020 at 08:51 AM

Looks great Steve