Cool Transmission

[gears]

Immersed in hot contaminated oil, yes. The difference in longevity comes from delivering cooled & filtered oil to the two most critical bearings, and cooled oil to the two heat-generating points (top gear and R&P). This is obviously most true with an off-road race car, but benefits exist for road cars too (especially hard-driven ones).
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aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[Krochus]

The biggest benefit with this would be the ability to filter the oil under pressure

Keep us posted. I’m interested in that pump’s performance. I’m looking for a oil supply pump for a rear mounted turbo setup in my 65 Chevy truck
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1970 Turbo Baja Bug Turbaja 2165 t3/t4 Speeduino sequential EFI LS3 coil on plug ignition

1965 Chevy c30, Microsquirt turbo aluminum 5.3/nv4500

[spencerfvee]

do you have to use a bigger hole to .vent the case .? all that oil from the pump might build up presser in the case . and might cause the seals to leak just my thought . some thing to think about

[halbug]

[halbug]

The transmission wants cool, filtered oil - so I take it

While the transmission is opened again I have added the Berg recommodations for additional oiling as well. The bearing retainer is modified differently from the recommodation. Below is why.

The #5 gear, its bearing and the rear main shaft bearing will get a supply of fresh oil

Gears #1-#3

#4 and hopefully some more oil will find its way to the main ball bearing

I am still pondering the ideas for R&P and its bearing

All the fittings entering the housing will be fitted with a jet to direct the oil more towards its target point.
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Stealth Ghia Transformation: http://www.thesamba.com/vw/forum/viewtopic.php?p=7226044&highlight=#7226044
My Berg5: https://www.thesamba.com/vw/forum/viewtopic.php?t=730276&start=0

[FreeBug]

Ok, if no one will be the prick to say this, then I'll do it:

I think what you are doing is cool, and thanks for sharing!

But...this is not much of a problem in the first place as I understand it, and you have introduced quite a few points of potential failure.

There. It's said. Now please ignore me and carry on.

[halbug]

[rayjay]

Can you lube the R&P from the opposite side cover ?

I would suggest "bench testing" the pump and your jets [ orifices ?? ]. Source some large clear container [ 3 to 5 gal ], assemble the pump and one of your jets, heat up a container of dope and then pump the dope to the jet which is aimed into the large clear container and see what sort of stream your jet provides. Then plumb up all the jets, lines , filter, etc and see what sort of stream you are getting from each jet. May have to make some drastic changes to orifice sizes, etc.

[ALB]

[rayjay]

Also, several strategically placed magnets can do wonders for keeping ferrous junk out of the lube. This would be especially applicable to every tranny with no pump and filter. I have been tinkering with a lot of JD hydrostatic transmissions for the past 8 years and they have at least 2 or 3 app 1" dia x 1/8" thick magnets at various critical points in the trans. They always have some fuzz on them. Some of these trans have pumps and filters and they still put the magnets in them.

Be good for the motors also.

[slalombuggy]

I'm not sure if he is thinking the holes in the case will be points of stress where cracks could start or if the external oil lines could be points of fluid loss. Neither of which I feel is a problem.

First, with the tapped holes in the case. This transaxle isn't going to be subjected to high shock loads like in a drag car, where people weld drain plugs shut and do all they can to brace the gear stack. This is more f an endurance race mod, where the gear box will be subjected to high loads over a long period of time, but no so much hi sudden loads as in side stepping the clutch at 5000rpm.

Second, External oil lines are nothing new, look at a top flight VW drag race engine, there are several external oil lines for dry sumps, full flow filters, spray bars for heads, external oil pressure relief. You just need t carefully route the lines and protected them from road debris or moving parts.

I'm actually surprised that this has never really been covered before. I thought with the vintage guys that road race something like this would have been done before. Thanks for sharing, cool ideas

[rayjay]

I doubt there is going to be any substantial pressure. I think I would use an Oberg or Canton/Mecca screen filter so I could look at the element.

[chrisflstf]

How do you know the oil temp is too hot? How will you measure your results to see if what you have done is working or not?

[risk]

To me the cooler is just a bonus. The added oiling jets are going to give the most benefit.

I would definitely add a filter or some type of screen to protect your pump at least. Not sure that cold gear oil would even try to seep through a paper element so maybe stick with steel mesh type filter?

I have used one of those Marco pumps as a turbo scavenge pump. Worked very well and held up great.

[Bulli Klinik]

A check valve and a small tank and you've got a dry sump trans. No oil for the gears to slog through.
_________________
I've never met a Bus I didn't like.
Mike K
Bulli Klinik
Colorado Springs

[vwracerdave]

I don't see any need for cooling the gear oil in a VW transaxle. I've read in the past that gear oil never gets above 160*. I'm sure if cooling the gear oil was necessary all the off-road racers would be doing it a long time ago.
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2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK
Featured in Dec. 2001 HOT VW's Magazine page 63

Watch my racing video's http://www.youtube.com/user/okvwracer/videos

[halbug]

I can’t believe the attention this is getting - and appreciate all the comments - a lot! Thank you all!

“Using our collective intelligence positively creates innovations that improve our cars.”

Ok, let’s try to answer…

I tried to think of a way to positively oil the pinion bearing and R&P… but then again, they are really trenched in oil or even submerged in it. So as long as my oil is clean and not too hot…

I will bench test the complete set up outside of the case:
Pump switched on at 130F - Pre Filter (some mesh type) - Pump – Filter with Magnets – Thermostat – Cooler (if oil reaches 170F) – Distributor – Jets – any oil in access of tbd? psi will enter the case directly through the oil fill hole.

This should give me good clean oil, pointed to where it is needed and cooled if is getting too warm. And yes, maybe the cooler is just a bonus – personally I believe it will get its workshare. After all I am expecting inreased longevity

The bench will get me a good feel for how it is working and to determine how far I need to open up the jets. Isn’t an orfice just a reduction in available open diameter? I will be using the mains from our the good old PCI’s

I put the transmission temporarily back together today, to mount it into my chassis. This is also a good opportunity to see if a skid plate may make sense…

Time to do some package work on the rear end including the transmission…
Once done, the transmission will be send to a professional builder for final assembly and the installation of the Peloquin diff.
_________________
Stealth Ghia Transformation: http://www.thesamba.com/vw/forum/viewtopic.php?p=7226044&highlight=#7226044
My Berg5: https://www.thesamba.com/vw/forum/viewtopic.php?t=730276&start=0

[TRS63]

I have been silent until now as I an more learning here than anything else.
But I find this topic and the discussions really interesting. Really like the way you are approaching things Thanks for sharing!
Cheers
Antoine
_________________
Antoine
My 62 ragtop daily driver:
https://www.thesamba.com/vw/forum/viewtopic.php?t=728873
My 914 restoration&lightweight project :
https://www.thesamba.com/vw/forum/viewtopic.php?p=9698432#9698432
Resurrecting a 60 ghia : https://www.thesamba.com/vw/forum/viewtopic.php?t=713906
My 52 Standard Zwitter :
https://www.thesamba.com/vw/forum/viewtopic.php?p=10086685#10086685

[tzepesh]

I'm surprised nobody mentioned the Porsche 915 transmission. Some of them were equipped with cooler from factory. I removed one from an '84 911 3.2, so not a race car. These also had a built-in oil pump. It was necessary to remove the complete system to install the gearbox in a VW 1303.

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'74 1303S, L98B Viperngrun (extra glitter), German Look
'64 1200, Sea Blue, under restoration

[Bruce]