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I think it's one of the best things you can do to any type 1 or 3 engine, stock or modified. Heads will run cooler (and more even), valve springs (and maybe even guides) will last longer and there will be less wear in the lifter bores. The factory didn't do these mods because the engine got acceptable life without them, and they just added more costs.

We've discussed this before- take the trouble to use the search. More later.  Al

When I was going to build an engine for the Spyder I intended to do this mod. Even started trying to source an old spent case to practice drilling on.

That said...

Realistically, with the mileage these cars get, it's only worth it for a very few. Danny P drives very hard. Stroud drives long distances. Maybe Musbjim but ptobably not. (Jack Crosby already has a Type 4 with factory Hoover mods). 

Most of the rest of us would not be driving hard or long enough to justify the effort (and risk—a mis-drilled hole could finish your case).

So, in conclusion, if you intend to race the car or drive it as if you're racing, and you intend to drive it a long way for a lot of years, maybe it's a good idea to think about this.

But if you're not likely to put a lot of hard miles on it, then don't worry if you don't have this top cylinder oiling improvement. 

 

Agreed, Ed. Hoover mods are great, especially for constant hi-speed running aka racing. This summer, I did a top-end rebuild. I sent my heads to California(Headflow Masters who built them in 2002) for a refresh. He did a valve job, replaced the guides, and cut a few thousandths of the cylinder seating surface.

There was exactly one problem: one exhaust valve was pitted on the end of the stem. This was most likely because I hadn't quite set the rockers up to properly rotate this one valve. He welded it, ground it and heat-treated it, and back in service it went. And I re-shimmed the rockers when I set it up. Good for another 45,000 miles. 

I installed new Mahle cylinders, set the deck heoght, and put in the Total Seal #2 compression rings. Case was not split, endplay measured .005" and oil pressure is perfect. Good to go.

Engine is running superbly and no more blow-by.

Some reading here- https://www.speedsterowners.co...agination.sort=SCORE

Mark Thurber (on the Samba and he has a Speedster body/used to post here, although I don't remember his screen name) has obtained excellent results using a 3/16" drill (which will flow enough oil to keep the head constantly bathed) in a couple of engines he's done. everyone on the Samba and Cal Look Lounge that's taken the trouble to do all the modifications say it's worthwhile. Re breaking through the outside of the case-

Bob Hoover mod case drilled throughYeah, it happens, as the castings and machining aren't consistent. A friend and I drilled a junk case with a 3/16" drill bit and didn't go through the case. When drilling the cam bearing boss, take the time to note the exact direction of attack through the boss to the horizontal galley- they're not all in exactly the same place. After, we drilled through from the bottom of the depression to see how much material was there- maybe 1/16", which I don't think is enough. Before attempting to drill the horizontal galley extension I would sand the depression to clean metal with fairly fine (220? grit) paper, then with paper rough enough to gouge the magnesium and give the epoxy 'tooth' to hold onto (I'm thinkin' 60 or 80 grit here). Pour 3/8 or 1/2" of epoxy into the area, let it cure and now there's enough material that there's nothing to worry about. If you can find it use Aluminall (don't know if it's still available) or something with a metal component. And even if you leave the case bare I would put a coat of paint in the depression area so the magnesium around the epoxy isn't exposed to air and start to corrode.

I think a case that's been broken through as above isn't necessarily lost- prep the area as described above, put a layer of scotch tape on the solid end of the drill and install in the galley. If you can cut a small enough piece of tape to just cover the hole/visible part of the drill bit that would be great as well. Pour the epoxy in, let cure, pull out drill bit, redrill the passage to clean up the tape, blow out and voilà- it's fixed!

Once upon a time as a much younger man I spent a winter working in a friend's VW repair shop and as well as drinking far too much beer after work (but what is too much, really, if you're with good friends and not married?), noticed that all the high mileage stock engines we took apart had more wear and scoring on 1 set of rockers than the other (and always the same side). And if 1 head was worse shape it was on that side. As I've said before, even a stock engine will benefit from more oil to the right side of the engine.

Hope this helps. Al

IaM-Ray posted:

Do the known builders do this in their cases?  Like CB?  Just wondering after all these years if this was implemented.

Not as far as I know, Ray. There are some engine builders that take the time for their     own road race engines (and now will not build a performance engine without these modifications), but a lot of builders (especially the drag race oriented guys) are of the opinion that their street engines survive without this extra work (and remember, extra work means the cost goes up, and VW people are generally pretty cheap).

One member here who 2-3? years ago had some case prep work (and maybe assembly to short block?) done by Competition Engineering (Arizona?) was told that they'd been building engines for years without the modifications and they didn't see the need to change now. And they are right in that the engine will run without the mods- but when you know what they do, coupled with the fact that they're not that difficult (ok, it's a little unnerving drilling into a case the first time, but like everything else once you've done it you wonder what the big deal was) I seriously don't get why more engine builders don't/won't incorporate them into their builds. I can see people being scared of breaking through and thinking they've ruined a case, but ½" of epoxy changes that.

Interesting that VW, in the design of the type 4 engine, realized the benefits of getting  oil to the right head full time and incorporated these machining steps into the assembly line. Gene Berg Ent. used to sell modified lifters (which helps) but the oil galleys need to be connected to receive the maximum benefit. Some guys, when modifying the rockers and shafts, go so far as to drill holes or slot the rockers to act as spray bars so the springs (and guides) run cooler. You can even drill the pushrods to act as spray bars.

You'll have to ask CB what they do/don't do. Al

Last edited by ALB

Yep yep. Any road race engine ought to have it, and any other engine will benefit from it. But if you don't have it, I would not break the engine down and start drilling. If Danny could get 45k miles out of a big, strong type 1 driving in his style, that tells you all you need to know.

Full flow it, balance the internals, balance the internals, use quality parts, check your end play and etc. and assemble it clean, torque to spec. and if you forget to drill out some oil galleys it's still going to be fine for a lot of years. 

When my engine gets torn down again, I'm going to do this. When looking at modifications, especially those that increase longevity, I see no reason not to. I was always concerned about "breaking through"-- but with epoxy as a net, I think I've got the confidence to do it. 

A business will not look at it that way-- the questions in business are, "Is this necessary?" and "What are the risks?" The risks are high, and the benefits are years down the road. You're going to struggle to find anybody that wants to do this (besides VintageVolks, the guys in the YouTube). If I were building engines for a living, I wouldn't want to risk doing this either.

edsnova posted:

Yep yep. Any road race engine ought to have it, and any other engine will benefit from it. But if you don't have it, I would not break the engine down and start drilling. If Danny could get 45k miles out of a big, strong type 1 driving in his style, that tells you all you need to know.

Full flow it, balance the internals, balance the internals, use quality parts, check your end play and etc. and assemble it clean, torque to spec. and if you forget to drill out some oil galleys it's still going to be fine for a lot of years. 

Very shortsighted thinking, Ed. The type 1 oil/lubrication system was designed for a low revving, low cost commuter car. The modifications are not difficult and are a noticeable improvement- if your engine is apart why would you not do them?

@ALB I don't disagree. If you're building an engine or have one apart, sure, why not do it? I just don't think it makes sense for most of the guys who frequent this board to tear down their running engines (most of which see little mileage of any kind an zero racing) to drill out the case like the old school VW road racers learned to do it in 1967.

It's simply not a reasonable worry for us that not Hooverizing the mill will result in breakage, particularly given the myriad other things, foreseeable and not, which routinely sideline these atavistic conveyances.

I am also aware that mine is a subjunctive (if not entirely moot) point as, regardless of any other factors requiring unscheduled maintenance, there are fewer than a handful of people here who are likely to find themselves staring, greasy-handedly, at their two case halves any time in this century. 

 

edsnova posted:

... It's simply not a reasonable worry for us that not Hooverizing the mill will result in breakage, particularly given the myriad other things, foreseeable and not, which routinely sideline these atavistic conveyances...

^ I agree 100% with this. No builder is going to do it for you. 99.99% of the high-performance Type 1 engines in service have not been Hooverized. If it's apart, and you aren't terrified of doing it yourself, I'd say "go for it".

Otherwise, it's a lot like advocating a 750 calorie a day vegetarian spring-water-only diet. It's probably the best possible way to live longer, but nobody is going to do it.

Last edited by Stan Galat

 

Having watched the video, I'm reasonably confident that this is something I could actually do.

Except that I'd probably end up completing the perfect drill job on the wrong half of the case.

Or I'd find out after the engine was completely reassembled that I should have used a 3/16" drill bit, not a 3/32" .

Or, again after reassembly, I'd discover that I couldn't find the drill bit anywhere, leaving only one place where it could logically be.

Or, after the perfect drill job, the engine stand would get wrapped up in the cord from the drill, which I'd trip over as the phone rang, pulling the engine case into the side of the car, requiring extensive fiberglass work and a $1500 repaint.

Or... well, you get the idea.

There is certain work on these cars that is simply best left undone by those of us whom fate is just itching to teach further lessons in humility.

 

Sacto Mitch posted:

... Or, after the perfect drill job, the engine stand would get wrapped up in the cord from the drill, which I'd trip over as the phone rang, pulling the engine case into the side of the car, requiring extensive fiberglass work and a $1500 repaint....

That part is particularly painful, as something very similar happened two weeks ago.

Stan Galat posted:
Sacto Mitch posted:

... Or, after the perfect drill job, the engine stand would get wrapped up in the cord from the drill, which I'd trip over as the phone rang, pulling the engine case into the side of the car, requiring extensive fiberglass work and a $1500 repaint....

That part is particularly painful, as something very similar happened two weeks ago.

Saying that and not explaining yourself is like reading a mystery novel front to back only to find out the last chapter has been torn from the book so you don't know how it ends. 

Spill the beans Galat.

Robert M posted:
Stan Galat posted:
Sacto Mitch posted:

... Or, after the perfect drill job, the engine stand would get wrapped up in the cord from the drill, which I'd trip over as the phone rang, pulling the engine case into the side of the car, requiring extensive fiberglass work and a $1500 repaint....

That part is particularly painful, as something very similar happened two weeks ago.

Saying that and not explaining yourself is like reading a mystery novel front to back only to find out the last chapter has been torn from the book so you don't know how it ends. 

Spill the beans Galat.

Yeah, Stan, you should know you can't leave something like that hanging and not finish the story. 'Cause no matter how humiliating it is, you're not the only 1 who's been there... 

ALB posted:
Robert M posted:
Stan Galat posted:
Sacto Mitch posted:

... Or, after the perfect drill job, the engine stand would get wrapped up in the cord from the drill, which I'd trip over as the phone rang, pulling the engine case into the side of the car, requiring extensive fiberglass work and a $1500 repaint....

That part is particularly painful, as something very similar happened two weeks ago.

Saying that and not explaining yourself is like reading a mystery novel front to back only to find out the last chapter has been torn from the book so you don't know how it ends. 

Spill the beans Galat.

Yeah, Stan, you should know you can't leave something like that hanging and not finish the story. 'Cause no matter how humiliating it is, you're not the only 1 who's been there... 

Here, here!  Or is it hear, hear?  Here, hear?  Hear, here?  There are so many questions in life!

LOL Gordon. Kind of like when I hit the garage door opener and forgot the Spyder was way high up on the lift. The door just touched the headrest and scraped the clearcoat on it. Not too big a deal to fix, but an unnecessary one due to forgetfulness.

If I ever leave the lift up now, I flip off the breaker for the door opener. Live and learn.

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