i m running a set of O'Brien s aluminium covers...they re taller then my stock dodge steelies were...and they have internal seals....but i don t have the 426 style.boots yet....wondering how they fit the aluminium covers.....
I'll just add this. Mopar used three different length plug tubes. So for the most part, you can swap tube lengths to suit your needs. Some were made of steel, which can be modified if needed. There are also the repro tubes (which they would not give me the length of), as well as the Moon tubes, stock 426 tubes, and custom "426" tubes in virtually any length you could imagine. Spark plug tubes should not be an issue.
These are pretty trick if you are using stock covers, dont want leaks, and are using the 426 boots. I should add that this is not my product.
I like those. I was going to let ya know I contacted that new york resto mod guy that is selling new tubes on ebay. His are 6 1/2 in length. If some one has the ability to flare them out after cutting them down to the size you need it would work.
Originally Posted by 73RR The problem that I have with not using the wire covers (which I actually like) is keeping garbage out of the tubes. Yes, a 426 boot can be installed but it really dosen't 'seat' on anything, the grip on the wire is all that keeps it in place. And, yes, if you use 8mm wire then the grip is stout. here's a pick of my Dodge....the 426 boots seem to suck onto the cover
I'm running a set of those on my dragster. The are great! I had made some aluminum spacers that are similar for my coupe before I saw these. My homemade ones also fit the 426 caps but don't have the threaded part to hold them on the valve cover, The are countersunk to fit on the flared part of the tube and hold down a stock seal when the plug is tightened
I've read this thread and one thing still confuses me....why would it matter if you are running the spark plug wire 'troughs', or cover, as far as the washers are concerned? It seems to me the cover is nothing but a cover and the spark plug tubes couldn't care less if they are there or not. What am I missing?
When the tray covers are screwed down to the valve covers they push down on the washers, compressing the rubber seal between them and the valve cover.
Regarding using the compressible spark plug washer at the base, I've always used a thin steel machine bushing (washer) between the base of the plug and the plug tube. I use one that is the same diameter as the flat base of the plug tube. It gives just a little more area of clamping at the tube base, so keeps the aluminum from compressing quite so much. Also, I've noticed that there is no rotational scarring of the tube from the plug being tightened against it, since the interface between the washer and base of the plug is where the "slipping" happens when the plug is tightened. I've been running the same plug tubes in my New Yorker for 56 years, and I expect that they'll outlast me. Remember when they were called milk tube? You old dairy farmers will know why we used to call them that.
I don't understand the theory......is this how the originals were? Wouldn't the washer that comes with the plug help reduce the wear on the tube & lessen the tendency for the alum to mushroom out on the bottom end? If it all seals up with the correct amount of torque, why does the ring need to come off?
It doesn't need to come off...it's just how they were done originally. I guess you could argue the plug will fit into the chamber further - the thickness of the washer -and that might offer some benefit. But it probably makes just as much sense to leave the washer in place for the reasons you mention. It's funny....guys will change, modify, or tweak practically every piece of an early Hemi then get bent out of shape over a spark plug washer. I guess the key is to refer to the use of a washer as a hop-up trick; that way no one can accuse you of being too dumb to remove it.
The tube bottom replaces the washer. The tubes were considered a consumable item that would be replaced if it became worn. leaving the ring on the plug reduces the pressure are vs the width of the plug bottom. Never actually looked to see if using the narrower ring could possibly bend the edge of the tube into the hole in the head & cause a leak or not.
I really don't think that the plug washer matters. In the digger engine I've made enough cylinder pressure to just about push the copper head gasket out once but have never seen any signs of an issue with the tubes or plug washers.
One thing that I can add is that K S Pittman wanted the plug gaskets to be removed. But then , I think that the tubes were more available. I really like the idea of the machine bushings.
So, the ID of that washer is just enough to clear the thread of the plug, right? How thick did you make them? Stainless ? Yeah, when cleaning up the 331 tubes, they reminded me of the tubes on on the ol' Surge milker. Maybe they'd fit ??
I bought some tubes a while back (years) and now as I am finally putting the engine together I discovered that they were too long. So I decided to shorten them instead of ordering more. Here is the tool I made to reshape them. Once I determined what length I needed it was easy to make them all alike.
I service aircooled Porsche 911s, and found that these 84-89 911 Carrera plug connectors fit perfectly. They also come with an upper seal to keep water and crud out of the tube. Looks like I need those upper washers.
I suppose there are a few variables like valve cover gasket thickness that would effect the compression of the seals we are discussing. I got a nice tight seal on the tubes without the washers (reminds me of a joke about penguins but this isn't the place). And I ended up leaving the rings on the plugs because they wouldn't come off without a fight. I ran both past Hot Heads and they confirmed this is perfectly fine.
I have sets of tubes for sale in the classifieds $30 per set and I also have the stock washers as well