Steps to scratch build a VW

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Little Scrapper

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Bob Hoover has a measurement for drilling the passage in the case as 8.872" or 8 7/8" long. I mark my long drill bit with several wraps of tape and I stop about an 1/8" short. Then drill the passage down from the cam bearing saddle and both holes should just touch. Then finish both drilling . Have drilled 3 cases with no problems. To me grinding the grove in the rocker arms is the hardest part of the mods. But now it look like you can buy new rocker arms already grooved from CB Performance .
Thank you.
 

Pops

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TAPPET_SCHEMATIC.jpg MODIFIED+SYSTEM.jpg Not all of the cases are exactly the same. As Bob Hoover says that distance can vary. If you drill to deep with the long drill you can drill out the side of the cam bearing saddle. Not good, will be a why did I get out of bed days :)
These are Bob's pictures.
 

Vigilant1

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dmar836

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The flathead guy’s have the same zinc issues. Apparently, after all the oil drama and debates it’s the casting of the cams that’s the issue. The zinc helps, and I will run as much as is appropriate, but isn’t the sole reason for cam lobes being wiped out. It’s not just VWs. As far as I have read/heard though zinc is about all you can do. That and don’t run “high performance” spring pressures for no reason a even if they come in the new kiddie heads. Who has valve float at our rpms? That would be one evil slope!
 

karmarepair

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So let's take a break here and write down what when wrong, why it went wrong and what you would do differently of you did it again. Anything that comes out of that conversation would be all upside.
The video linked up-thread does a good job of describing what can go wrong with drilling the case to get more oil across the engine. I don't have that case anymore, so I'm going by memory. I did not have a very good setup for drilling down from the cam journal, and I think the bit drifted. When I tried to connect that drilling via the gallery drilling, which is sort of self-aligning, the drillings didn't meet. Drill a little more, check, drill, check, and suddenly I'm through the case into the sump, I think via the long drilling through the galleries. But the error was actually from the other direction. It was a junk case anyway, so the fact that welding magnesium isn't in my capability didn't matter, but it made me shy of doing this on a brand new case - $500 at the time, now closer to $900.

I was using a Portalign on a hand drill to try and keep everything straight drilling down from the cam journal. In the video, they set that up on the table of a Bridgeport type mill. If I had to do it again, myself, I'd get the longest drill possible to magnify any mis-alignment, clamp and shim the case to the garage floor or workbench so it was dead nuts square and level, and go REALLY SLOWLY. Maybe use a bubble level ON THE DRILL. Or I'd put my bench drill press on the FLOOR, with the table and the base swung out of the way and the case secured as before.

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I think it was Pops that mentioned he was challenged making the grooves in the bore of the stock rockers. That bore is quite hard (as in Rockwell hardness), and you have to reach down into it to connect the two oil holes. What I did was get a teeny diamond wheel for my dremel, chucked it as far out of the collet as I dared, and went after it freehand, using the edge of the wheel to form the groove.
 

AdrianS

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I don't know if you get it in the US, but we use Penrite in older design competition engines - they have a "full zinc" range.
 

Pops

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No one in my area cares Valvoline Racing Oil . That is all I used for decades.
 

Vigilant1

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No one in my area cares Valvoline Racing Oil . That is all I used for decades.
Last time I ordered it from the auto parts store, it was still cheaper than Brad Penn.
Last week I saw VR-1 on the shelf at Menards, that surprised me. I'll try there first next time.
 

Pops

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Last time I ordered it from the auto parts store, it was still cheaper than Brad Penn.
Last week I saw VR-1 on the shelf at Menards, that surprised me. I'll try there first next time.
I can't get anyone in my area to even order it.
 

Pops

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Dennis DeFrange

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Dam , guys I didn't even like um till I started following . Might look at puttin two of um on my Smith . That would be a first at the Osh . Excellent thread , keep it up .
 

103

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Thanks for letting me know where I can get it.
I'm just about 60 miles from the refinery where its made and no one will carry it or even order it.
I use the Valvoline VR1
20W-50 in the summer I get it from my local Ag Store for $2.50/quart. IN the Winter I use SHell Rotella T4 10w-30 from the same ag store or many others for $13/gallon. The ZDDP content is high enough for flat tappet engines that have been broken in.

William's Oil Change Video speaks to goo practices and the advantage of ZDDP in flat tappet engines.

 

BeemerNut

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Dealing with any flat tappet era engines and vehicles all run flat tappet pre Cat era plus Cat era street legal Calif. vehicles. Adding Comp Cam's Break In Oil Additive at every oil change long before the EPA started slowly reducing zinc and phosphorus in oils. High concentrations of zinc and phosphorus protection era long gone but not the engines. With roller lifter equipped modern engines they can operate without these additives, EPA pushed that bill.
Synthetic about the only advantage I see is it can stand slightly higher temps before breaking down turning into carbon, best used in race engines pushing oil temps to the extreme temp limits already. I also add zinc and phosphorus additives to synthetic oils used in flat tappet engines. Engines requiring leaded gasoline now running on unleaded another engine's slow death exhaust valve seat and valve face disaster, another different topic altogether. Union 76 110 octane leaded gas mixed with unleaded in the 60's & 70's era motorcycles. Redline Lead Substitute additive to unleaded gas out on the road and return trips home. Old leaded valve seat and valve engines maintaining solid valve clearances no recessions. Cams and lifters also not showing any scuffing or wear marks at all on hard working high temp air cooled bike engines. My 2 cents.......~~=o&o>.......
 

BeemerNut

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Hey "103" Valvoline VR1 has great engine oil protection, great for short run engines like drag racing but used on the street gathering miles your gonna end up with a sludge monster really quickly. Ugly buildup within 10,000 miles what I saw on a factory new engine after break in starting with dark a light turning to brown coffee stain looking internals, later mileage sludge starting to build up.
Even diesel's Delo 400 the good additives have been removed with people still thinking they are protecting their engines when they are not.....~~=o&o>......
 
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