Need some help... I'm building driveshaft style "lakes" headers for my Hemi. I'm going to run cutouts and need to make some plugs for the header part. I don't want to run flat plates with wing nuts so I was thinking of running an expansion plug up in the tubes, just after the cutout pipes so you can't see them. Like these: Simple, right? Nothing fancy. Problem I'm having with these is they're NOT for high temp applictions. +225* F, seems to be about the most they'll take. I know silicone rubber will handle a great deal more than that, but I can't seem to find such an animal out there that would work like the ones in the above picture. Have any of you done something like these? Steve Sellers did something similar that plugs the ends of the pipes. They are SUPER cool! I've been trying to get ahold of him to ask what the materials are, but it's tough to get in touch with him now. Here's his slick little caps, in case you haven't seen them: Anyone have thoughts or experience with plugs that will handle the associated heat of headers? I was thinking these need to handle running temps of around 350 or 400 degrees, maybe more, so they don't get stuck in there when I go to uncork them. Anything you guys know of that's off the shelf would be appreciated. Otherwise I'll have to custom make something. Thanks!
If that doesnt work the 1952 california bill fisher book says to use a gas cap and neck on the end, havent really seen anyone do it to know how well it works, but should look slick
Yeah, I've seen that! Very cool! I would still rather they up inside the pipe where you can't see them. Trying to keep them real clean looking with nothing bolted or capped on the outside. Always thought that filler cap thing was very clever though. I will do that someday.
I doubt seriously that his is an expansion plug. Most likely the center stud is welded to 2 struts welded from the inside of the collector. With the cap removed the stud remains. He might have a gasket or he might have machined up a beveled seal similar to the valves in the heads. The above aluminum cap is drilled and tapped on mine. It screws onto a center threaded stud. The pipe has a flange for the gasket to seal against. A center stud was popular before the standard lakes pipe fined aluminum 2 bolt plates became popular. The expansion plugs you showed are for plumbing pipe. You know you would take a lot of shit about turds falling out if they were removed. I made up a socket to spin it off when it's hot and tighten it up for a good seal. The secret to the screw cap on a threaded nipple is to get a brass screw cap. (not found in Home Depots) Some braze a bar across the face to act like a handle to get it tight. If you use a cast iron cap on screw threads it will seize up in no time. The brass cap won't seize as easily. Anti seize on the threads would be added insurance.
Yeah, the expansion ones shown are for plumbing, indeed. They are called "test plugs". The PSI rating is plenty high, but not the temp rating. Otherwise they would work, in theory. I was told that Steve's cap was the expansion type, but maybe my source was incorrect. I thought an expansion type would be slick because there is few parts in them. Just slide 'em in and tighten the wingnut. Maybe life isn't that easy though...
Scooter, some where on the H.A.M.B. is a thread about using a deflector on the basic cap such as the ones that "wing nut on". This stops the spoiling of exhaust gasses and was to aid in the travel of said gasses out the "quiet" side of the exhaust system when plugged. If this deflector was tight as in sealed it would lower the temps at the plug. Of course the exhaust tubing running under the car would have to tee off closer to the engine and further from the end of the lake pipe. Does this make any sense or help at all? Rick.
Yes, I know what you mean. I actually will be Teeing off closer to the engine itself because I need to dive into the frame right in front of the firewall. This will leave about 9 or 10 inches between the teed section and the plug location, but I could move it closer to the tee. Seems like it would still be in a high heat area though. Any idea what the name of that thread was? Anyone have a way to take some temp meausurements on their headers about 12 inches back from where the rear most exhaust runner converges into the cone?
Scooter How about mix a plug like Tommy showed and an expansion plug made from metal. How much of a taper is on the headers? If not much than this could work. If you make a plug that can slide against metal "fingers" welded to the cap that press against the inside of the header tude. This would seal most of the pipe off. THe inside lip of the outside plug can be lined with a seal of some sort. Maybe exhaust gasket material. That would seal off the rest. Give me a call if I made no sense.
I can see how the rubber plumbing plugs would not work. What about some sort of toggle bolt setup. Maybe weld a ring inside the exhaust that toggle bolts would hang on. That way you could still have the cool looking wing nuts showing.
what about a high temp rubber? get a block and make some dollar plugs out of it? all they are is a washer on each side with a bolt thru em to compress the rubber out. id pull em out weekly any way, to drain the water. my 58 had functional dumps behind the front wheel, and the first time i uncapped it there was a good ammout of water in there, from the condensation. dont need yer plugs rustin in....
Paul, no taper. It will be in the straight section. I thought about using a threaded "cleanout plug" and welding a threaded portion inside. Seemed like way overkill and a lot of extra work for something that could be accomplished with a simple expansion plug (if one exists).
Hmmm... interesting. Good thought! I will probably run them uncorked most of the time anyway. Excellent point though!!!
scooter, id be tempted to just try it. wont do much but burn the rubber a lil, and that can be cleaned with a wire wheel on a air grinder. i dont think the exhaust gasses are really the prob, but the temp of the exhaust closer to the heads heating the pipe and traveling down the header. my dumps at the end of my headers just had crap paper gaskets and they never burned out.....
I agree that my idea is fairly complicated but it might inspire you to find a good solution. I thought I would add a pic of my thought. Don't laugh I am not an artist.
Scooter, I have an infra-red hand held thermometer you could use. It is just like the one you see the racers using to check tire temps. Just point it where you want the temp reading and it will show surface temps. BTW, that Hot Rod is looking Badass! Gordon
HOLY COW! You're alive!! I was wondering how you are doing! I've got one of those here at work, but don't have a running engine to test it on with those pipes. Just had a thought though... I'll bring it to breakfast one morning when I know someone with lakes style headers will be there (Paul!! hint, hint). I have to make a decision about this before I start making the pipes, in case I need to weld something in during the construction. I don't want to cut them open to weld in a ring or something. Just doing some planning. I'm tempted to do as mentioned and just try one of the "test plugs". Anyone know how easily these come apart or IF they come apart? I could just replace the rubber ring with another material that will handle the temps, like silicone. Thanks for the diagram Paul. I'm with you... you artist you.
Scooter you can test in on my roadster if you like. I am sure the exhaust temps would be close between Hemi and small block. Why don't you come over to the house one night this week or weekend and I will ahve the wife make some dinner and we can bench race over a few beers. Since I already had drawn it before I saw your post, I had to include it just the same.
those plugs are just a rubber block, washer on each side, and a carrige bolt thru the whole thing. 6 parts. easy to get apart home depot has em, could check one of those cheep
Yeah, if they have the size I need, I could just pick a couple up and see what happens. Paul, this week is crazy, but next week I just might take you up on that. I'll come by and check out your "compound".
Scoot your ever thinking it too much, its kinda simple if you have a Lathe, Think Stainless!! Heat=? e-mail me
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