Now I’ve been hesitant about attempting this mod for weeks now. Hell, I event debated about it yesterday.
I don’t know if it was the perfect case tapping going to my head or what but I blew out the debris and measured things again.
I started the long tap through the lifter bore and stopped where I thought I should given how far I went past the bore. I then attempted to slowly drill the new #3 cam saddle hole millimeter by millimeter, stopping to clean out the shavings.
And then… I fucked it up.
I thought going on a slight angle in the cam saddle would help to intersect the area where I estimated the lifter bore hole went.
There wasn’t even time to really catch myself when the drill went right out the side of the case.
I swear… if that area was partially filled in on the mold, when the case is cast this mod wouldn’t even be something to worry about.
So… I couldn’t really get angry. I mean, I knew the risks. I’d done my research. My measurements and estimates of where the galleries would be safe was so far off.
So what to do now?
Well… it was a small bore I drilled.
I managed to get the 1/16″ tap in from both the inner cam saddle as well as the exterior and was able to tap both sides. The inner one much better than the outter due to a slight curve in the case there. However, I’ll try that again. (It would be easier if the tap was about 2 inches longer than it is.)
The plug fits perfectly in the #3 cam saddle hole.
I need to read up the ideal sealant, but I am thinking that if I use the high temp oil resistant Loctite on this plug, then fill up the space between plugs with a sealant, then the threadlocker again on the exterior plug, followed by J-B Weld ExtremeHeat to cover the outter plug (and perhaps the inner one as well) then I think that should work for this engine.
I mean, it isn’t going to be much more beyond say 70HP on a good day. And there shouldn’t be the kinds of massive case pressures going on internally, especially with the planned venting of the oil breather back into the 1-2 side carb.
It can’t hurt to try.