I'm working on modifying the exhaust on my roadster, in order to occasionally un-cap it. Right now it is just straight through the mufflers. I've found a good spot to cut/weld in a pipe and route it out under the cowl area of the car with a stainless 2-1/2" pipe. I want it to be simple to uncap and pleasing to the eye. These pipe plugs have caught my interest. McMaster-Carr lists a rubber one and a high-temp silicone version. I would use a little different, larger, more vintage-looking wing-nut. http://www.mcmaster.com/#tapered-expansion-plugs/=l6giiq I also like the appearance of these RUBBER plugs and they have lots of size options listed. My only worry is that the rubber won't stand up to the heat of the exhaust. It will end up being installed only about 18-24" from the outlet of the headers. http://www.shawplugs.com/turn-tite-expandable-rubber-plugs-c-249.html Have any of you used plugs like these? Any words of experience or photos of them installed? Thanks! Malcolm
What an intelligent response. Geez. Two thoughts; first, have you considered a 'butterfly' style cut-out? That may be more period (albeit more prone to leakage). Second, what about a more standard 'lakes' style cap? Certainly 3 wingnuts won't take much longer than 1...
Won't they melt?, They will melt! 2 foot from the block? Go look for sanitary fittings from Stainless they make a flat plate with a teflon seal and a clamp that goes around the end of the pipe and cap...Plus they use them at Budwiser Beer so they have to be good
http://www.swagelok.com/downloads/webcatalogs/EN/MS-03-05.pdf Go look for Butt Weld Ferrules and solid end caps with teflon gasket and clamp
Back in the late fifties, early sixties they were quite popular. Usually just a piece of 90 degree tubing with the short chrome piece about 8-10" long with the diamond shaped two bolt cap on it. They were referred to as "lakes plugs" and were quite a fad at one point. I installed them for several guys. They were not very efficient obviously, but made lots of noise, by removing one bolt and allowing the diamond shaped cap hang by the remaining bolt.This along with the amber or red clearance lamps mounted up in the fender wells (front, back or both) illuminating the 55 or 57 Olds Fiesta or Dodge Lancer spinner caps were the in thing.
Haha... I'll leave that up to you to try! I did actually consider both of those options.... but have a specific look I'm going for. My goal is to have clean pipe poking out below the frame rail and angled back, no flange on the end. I agree, the butterfly cut-outs do seem to leak, not to mention rusting closed over time. Thanks for posting the ideas! I've actually seen those in a brewery -- thanks for posting the link and idea! I know exactly what you're talking about - thanks for the idea! Most likely the way I'll go. I actually just ordered these really cool looking wing nuts. (it's the little things that count, right? )
If I were to use a rubber plug, I would also have a chain on the wingnut so that when it falls out it stays close to the car
This photo shows what I came up with. Will probably weld the wing nut to the stud, that way when it's unscrewed from the nut inside the pipe, you can easily pull the plug out (by pulling the wingnut/stud straight out). Pipe is 2-1/2". May need to saftey wire the wingnut. Will see how it works out when I start driving it. Also, who knows if the rubber (actually silicone) will hold up to the heat.
Well- silicone plugs I use for powdercoating,and have had them hold up at 500 degrees without melting.........But-nothing more to add. If far enough back,(away from the cyl head temp)they might hold. Gotta keep an eye on that one,but the idea,if it works out,is good.
What about adding a metal disk below the silicon plug (with a spacer between the disc and plug to maintain an air gap)? The disc would take the punch of the exhaust flow and turn the gasses as well as acting as a heat shield.
Sorry but those will get too hot to work very long-I give em 10 minutes at full heat......arent we talkin a Max 1300 degrees here? stands to reason it woud be near half that on the "cool" end of pipes.....
Well, the nice thing about the setup you made is that if they do melt you can always have one turned out of metal in the same shape to replace it. With metal you will get a little leakage but nothing significant. Don
I think those will work if not over 600 F, we manufacture Silicone molded products and they will hold up to 600 F. Might have a couple of spares I like em!
This is gold. REV.1.0 A cast iron square head pipe plug of appropriate size that fits with the threads turned off with a taper like the silicon plug. Hole thru the middle for the screw. The center is hollowed out on these big plugs to make them light weight. Frank
I'll report back in about six weeks when I have to have the car back together and running. Aren't exhaust temps around 500 degrees near the heads? gas pumper - Frank, thanks for mentioning that as an option! This idea started from Steve Seller's caps that he used to make. Again, the way I have this set up, I could adapt caps like his. Would ask a friend to machine aluminum caps/plugs to just fit in the 2-1/2" pipe. If I recall correctly, his caps were aluminum and I seem to recall reading the heat would expand them to provide a good seal. Copper washer is under the wingnut. (sorry about the crappy pic)
I use a cap and copper washer like the pic shown Nick.... My caps over ride the edges like a jar lid. But I use a center bolt to get a snug fit..... just like your doing.
When I was in High School in El Paso, TX a guy named Richard (?) Flowers had a Model A coupe with a SBC in it and used tapered drivelines and some of those flush floor plugs with the coupling welded into the end of the drivelines and ground flush with the tubing - looked pretty cool. I remember them being machined and having a female square but they were something like this.
Malcolm, I assume you do not want a flange (2 or 3 bolt) at the end of this cutout??? that is how most people do it, welding a flange to the pipe, and have a "no-hole" matching flange for the cap. then you can use a gasket to really seal it up...
I remember back in the early 60's guys would weld in gas filler pipes w/fill caps - just turn and twist off.
I figured it'd be good to report some results back on this thread. Along with some of you, I wasn't sure if these would work. I'm happy to say they've worked great! I have about 2,000 miles worth of driving with them installed. The wing nuts haven't moved a bit and the silicone rubber is still soft. They are fairly easy to remove and the car sounds great without them.
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