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The Empi external oil cooler with electric fan I bought recommends an inline remote oil filter as well.  Seems like a good idea.  My concern is that the kit I found says I need to modify the oil pump, including threading and tapping the case.? I’m not sure I am up for that.  1) is there any reason I need a remote oil filter, or 2) are there kits that don’t require oil pump mods?

thanks

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The pump body outlet needs to be blocked to direct all the oil out the cover, and then the engine case needs to be drilled and tapped for a fitting for the oil to get back in the engine (and to the bearings).  This is needed for either a full flow filter, external cooler or both (which is the smart thing if you're going to add a cooler).  There are pumps which direct the oil both in and out through the cover-  https://www.cbperformance.com/...ct-p/maxi26early.htm                                            but the last versions I was aware of had pretty small diameter passages in the cover which really restricted the oil flow above 6,000 rpm.   Since most street VW engines only go to 5500-6,000 rpm with power I don't see anything technically wrong with running this style pump.  Just be warned that if your engine revs above 6,000 rpm the pump will move more oil than the cover can and as well as starving bearings you can break the drive tang on the oil pump shaft (which means 0 oil pressure RIGHT NOW!).

Every engine, stock or modified, will benefit from a proper full flow filter set up.  Cleaner oil is always easier on the bearings.  And any stroker engine will usually benefit from an extra cooler.

Hope this helps.  Al

Last edited by ALB

Nobody seems to do it any more, but I also drill, tap, and plug the case main oil gallery out from the pump. This is on the distributor side of the case. I do this because it completely eliminates any possibility of oil pressure leaking by an ill-fitting oil pump. The leaks there get bigger when the engine gets hot.

@DannyP posted:

Nobody seems to do it any more, but I also drill, tap, and plug the case main oil gallery out from the pump. This is on the distributor side of the case. I do this because it completely eliminates any possibility of oil pressure leaking by an ill-fitting oil pump. The leaks there get bigger when the engine gets hot.

Ditto. Plus if you're feeling totally compulsive, there are always the Hoover Mods:

https://bobhooversblog.blogspo...007/05/hvx-mods.html

I love the reaction everyone has to the Hoover mods.

One a year, maybe twice, someone posts the link. Someone clicks. Someone says "holy crap I'm not building an Indy car or an aircraft!!"

It's like if you posted a video link to a guy doing open heart surgery on himself.

You can set your watch by it.

Hoover Mods separate the mad scientists from the mere madmen.

@edsnova posted:

I love the reaction everyone has to the Hoover mods.

One a year, maybe twice, someone posts the link. Someone clicks. Someone says "holy crap I'm not building an Indy car or an aircraft!!"

It's like if you posted a video link to a guy doing open heart surgery on himself.

You can set your watch by it.

Hoover Mods separate the mad scientists from the mere madmen.

Ikm surprised that none of the modern case manufacturers have incorporated it. If I was shopping, It would definitely score some points with me.

I have zero knowledge of the "new" aluminum cases.

The magnesium cases, however, I do. The first thing you need to look for is enough material to drill though for the Hoover mods. If there isn't enough meat there, you are done before you start. You must drill out a plug back by the flywheel and tap it for 1/4" pipe. Then you use a 12" long drill bit to extend the oil pathway.

The case I had attempted this had plenty of meat, but the factory drilled oil path was cocked sideways. So the drill bit was offset by 1/4", which would have ended badly had I extended the hole.

If you manage to drill this first hole, then it frees you to do the other mods: lifters and rockers.

I'll be doing this to a couple used cases(if they measure out as worth it) in the near future.

I did plug the oil feed by the pump on this case, and my customer is very happy. He has plenty of oil pressure on a 2276 with the CB dry sump pump. He has both the factory cooler and an external one, and all AN8 lines. He's put 1200 miles on the car in the last month. Previously, it had 500 miles over 4 years.

Last edited by DannyP
@dlearl476 posted:

Ikm surprised that none of the modern case manufacturers have incorporated it. If I was shopping, It would definitely score some points with me.

I asked Todd Francis, of TF-1 case fame, why he doesn’t complete the Hoover mod on his cases. What he does is drill the long hole connecting the lifter galleries, then leaves the last short connecting hole in the cam bore undrilled. He told me that some big name engine builders are not sold on the Hoover mods. There is plenty of discussion on the Hoover mods on TheSamba for interested parties.

Some of you know I went ahead and did the Hoover mods when I had the 1776 apart to clean it up from sitting new for 12 years.

All I can say is that I've had no oiling or cooling problems since (aside from that time the fan decided to explode). My breath is fresher and checkout girls frequently wink at me at the grocery (that might be because I often forget to zip up).

What does that mean? Bob Hoover developed his mods based on teardowns of type 1 engines used to propel aircraft. Having an engine failure at 10,000 ft above the ground is different than having to coast to the side of the road.

I'm convinced most of his mods are based on research and make sense, but may not make a lot of difference for the majority of us. I'm retired and enjoy tweaking things so...

Hypothesis: Hoover mods provide oil flow to critical areas of the type 1 engine and prevent wear, cool better than the stock design. They fail less frequently.

Null Hypothesis: They don't. Hoover mod engines fail at the same or increased rate as unmodified engines.

Rejecting the Null Hypothesis: Data should show that Hoover mod engines fail less frequently and upon teardown analysis show less wear than unmodified engines.

Evidence: Bob Hoover anecdotally said it worked. My engine is still working after 10,000 miles. Replication - haha.

Conclusion: We don't have enough data to reject the null hypothesis. Maybe it helps and maybe not. We just don't have the data to form a conclusion. So, maybe yes, maybe no.

And, as my dear old research professor taught us to say, "Never argue from a non-rejected null hypothesis."

I've said this before, but here we go again-

Yes, there is the possibility of drilling through the outside divot with some cases, but if that area was prepped correctly and filled with ½" or so of high temp epoxy beforehand it would be a non issue.  Even a case like this                                                                                Bob Hoover mod gone wrong...

can be fixed- sand the area with 100 grit sandpaper to clean metal, take a flat blade screwdriver and pull up to gouge the walls of the divot to give additional anchor points, wrap the drill bit with a piece of scotch tape and re-insert (this will keep most of the epoxy from flowing into the hole), mix epoxy, pour, let set, pull the bit out and re-drill as necessary to be sure the passageway is clear.

As for a number of engine builders claiming they've built hundreds of engines without the modifications and they aren't 'needed'- they are right, but there is also no denying that ANY VW Type 1 engine will run better (and longer) with them.  For those new to the conversation- because of the way the oil passages in the case are drilled and the design and movement of the camshaft followers, the right side head only receives oil part of the time (it's been said as little as 12%) and these improvements to the oiling system reduce lifter bore wear and flood the heads (rocker box areas) with oil, carrying away heat, WHICH MEANS THE HEADS RUN NOTICEABLY COOLER, VALVES AND GUIDES LAST LONGER AND THE ENGINE'S TUNE STAYS CLOSER TO OPTIMAL SO THE ENGINE MAKES IT'S BEST POWER A LARGER PERCENTAGE OF THE TIME.

During the winter of 1979/1980 and into that spring I had the opportunity to work in a friend's VW shop for 4 or so months and during that time I stripped down 8? 10? 12? (it was so long ago and there was so much beer drank after hours that parts of that period of my life are a little bit of a blur) high mileage stock engines in preparation for rebuild.  EVERY TIME, the rockers on the 1-2 side were noticeably more worn, with the head usually in (just slightly) worse shape than it's mate. You could see by the wear in the bushings (and sometimes the scoring on the shaft) which side of the engine they'd been run on, and when I laid everything out on the table for Don to assemble, the right side rockers were usually easy to spot and they would go on the other side. At some point (probably during an after hours beer binge) Don explained that the right side of the case didn't flow as much oil to the head, but didn't know of a fix and since it didn't affect longevity THAT MUCH (I was taking engines apart with anywhere from 80,000- 120,000 or even more miles), I promptly forgot about it- until reading Mr. Hoover's blog some 20? years later.

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  • Bob Hoover mod gone wrong...

@Nadodave

Since you're thinking about doing or not doing a full flow conversion, I wrote a 4-part article on this site that covers everything you ever want to know about doing this, including photos, as I went along.  I will let you read it and decide if you're up for this or if it is beyond your comfort zone.

I drilled and tapped the case with the engine still in the car, and also replaced the oil pump I had originally with a Gene Berg recommended pump for full flow, with the outlet already plugged for full flow.  To get the pump out, you will need an oil pump pulling tool (CB Performance about $30 bucks).  You will also need a specific drill and an NPT tap of the right size (about $50+ from Gene Berg or $40 from Home Depot) as mentioned in the article.

Let me just say, that drilling and tapping the case can be a big deal, especially if you have never built a VW engine before.  If you have some automotive mechanic experience, then it is certainly do-able.  It would certainly be much easier to get a kit that gives you a new pump with a cover that provides oil out of the pump and then back in to the pump in the same cover without having to drill/tap the case.  I have seen such kits in the past, but don't remember who sold them and don't have any experience with them.

Anyway, here is the starting episode of my 4-part article - All parts are up under "Resources/Knowledge Base" up at the top of this page for supporting members:

https://www.speedsterowners.co...ooler-upgrade-part-1

@imperial posted:

Anyone use the oil pumps with attached oil filter ?

i would think you could run an oil pump adapter on it and run lines for a cooler and filter ,   I just do not know the quality of the filter pumps !

There are these- https://www.cbperformance.com/...ct-p/maxi26early.htm                with both the in and out passages machined in the cover, which (for those hesitant to drill into a case) make adding a filter and cooler relatively easy. One caveat- someone tested them a number of years ago and found the small passages in the cover wouldn't flow any more oil (meaning low pressure and starved bearings) past about 6,000 rpm and when pushed, hydrolocked (the pump was pushing more oil than the cover would pass) and broke the drive tang off the drive gear.  I've always wanted to look at a cover to see if this could be remedied, but have never had 1 in my hand so I don't know if it's possible.  Since most modified VW street engines are done by 6,000 rpm I would think they'd be a viable alternative.

The filter pump will limit your exhaust choices, but I do know they work (with the same rpm restriction mentioned above).

And as Gordon said, it is possible (and really not all that hard- just a lot of work) to drill an engine block in the car for full flow.

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