After reading @jebbesen 's post about the headers and mufflers he built, I thought I'd throw this out on how I build mufflers. First of all, here's a link to his post: https://www.jalopyjournal.com/forum...school-driveshaft-headers-side-pipes.1131726/ The first set I built were for my 1956 New Yorker, and here's a youtube link to how the pair behind a stock 354 hemi sound: Those are a two-chamber version. The photos below are for a 3-chamber muffler, and while I built it for an O/T vintage thumper dirt bike, the process is the same, just scale it up. First of all, here's the inside pipe for the muffler before drilling. I calculate the number of holes I need to drill per chamber based on the area of circumference of the inlet, and upsize it 50% or so. The ring around the outside is a chamber separator. You need to put it on before drilling holes and making "scoops". Chamber separation inside the inner pipe is done using appropriately sized core/frost/freeze plugs. Shown here are the first and second chambers separated by a core plug inside the pipe. The holes are drilled and then a round shaft screwdriver is used to bend the holes into "scoops" that face the exhaust flow and grab the exhaust to direct it from one chamber to the next. The inlet is on the right, so exhaust flows into the pipe where it is forced out of the first set of scoops due to the core plug block which is in the pipe between the first and second groupings of scoops. It is forced back into the second set due to the ring on the left forming a seal between the inner and outer pipes. End caps. More core plugs, these the diameter of the pipe used for the outside of the muffler, and cut to let the inside pipe pass through. Easy to do on a lathe, pain in the ass otherwise. The three chambers, from left to right. The exhaust flows from inside to outside in the first chamber, outside to inside in the second, and back out through the third. I wasn't finished drilling the more numerous smaller holes in the third chamber, was still doing some math to determine the area of the holes I would need for flow. The ring on the outside between the second and third chambers is sized just a few thousandths larger than the ID of the outside pipe for a nice press fit. Once again the lathe is real handy to sneak up on the proper size. A view of the inlet, with the inner pipe pressed into the outer and tack welded. The drill chaff in the holes helps to soften the sound. They will eventually rust, break off and blow into my buddies face who always rides behind me. Side view of inlet end. Core plug tacked into the outlet end of the inner pipe. This is at the end of the third chamber, forcing exhaust back into the space between the inner and outer pipes. Another core plug the diameter of the outer pipe is welded onto this end, with a short curved outlet. Normally for a hot rod application the outlet would be straight instead of curved. As mentioned earlier, this particular muffler is for an O/T vehicle, and needed to have the exhaust directed to the side. The finished muffler at the top of the pic. You can ignore the lower item, it is a piece of plumbing that goes between an engine and the muffler I built If you're interested in the effectiveness of this particular muffler you can click the link below. This video was taken immediately after starting the engine, so no burned hand.
I can relate. Check these! The difference is you used some really neat methods and ideas to build yours. I "lazy ed" out and bought stuff!
Yep, copies of the 1970 GTO VOE mufflers. I built 16 sets with help from three great welders and many suppliers.
With everything else I had to fabricate in the building of my RPU I decided it was much easier just to order a pair of Porter mufflers. Mufflers are not something I'll be building when you consider the vast selection and affordability of what’s available on the market.
On the one in the pictures 1.5 inch inside and 2.25 outside. On the mufflers I built for the New Yorker I used 2" inside and 3" outside. I wish I would have built three-chamber mufflers for the Chrysler, may have to do that next time I'm snowed in.
It turned out nice. My speaker sucks on the lap top so I'm getting not the full effect but it appears well thought out.
I know mufflers are cheap to buy but building your own is satisfying! The sound is your own , like making a musical instrument. Those VOE mufflers are next level! Years ago I was trying to find some for a 70 Pontiac Lemans convertible that I had. I went to the GM dealer with the page from the shop manual that they were in and the parts guy just looked at me and said "don't make them anymore!" He couldn't care less , I was hoping that he'd go " yeah they got a bunch in XYZ warehouse I can have a set tomorrow" Fat chance....oh well.
Hey, Ebb, think I know the answer, but like to hear it from you. What is/are the reason/reasons you build your own? Super work, btw. Ben
If you thought the answer would be "because I can" then you would be correct. There's some satisfaction in seeing the finished product, and then hearing it work every time I run the machine.
Not too hard. Block of wood, long drywall screws, hole saws and a half round file. Hole saw the core plug OD in the block of wood. Cut the block in half through the hole. Screw the halves back together clamping the core plug in the hole. Clamp the assembly to the drill press or clamp it in a vice and hole saw the hole in the core plug. Dress the hole to final size with the file. I wish I had seen his earlier. I wanted a set of lower profile mufflers to tuck up under my channeled coupster. Wound up buying a set of glasspacks, cutting the end caps off, flattening the outer tubes and hammer forming a set of new oval end caps.( 2 3/4" tall 2 1/2" in and out) Budgets are a bitch.
And even if it doesn't work like you thought it should, you have figured out processes that can be used to fabricate other things as well.
Not exactly what I expected. Close. And a good reason that I often employ. The main reason for the "hopped up " 263 I did. Was expecting sound preference. Or "looks" on the bike. Ben
Ebbspeed, your's sound awesome! Even though these videos show later year cars, several HAMB friendly vehicles rae running them now. Some of the new ones are on older trucks and 1964 cars and are still working after ten or more years. , Yes they are really slick to hear and operate and like EBBSPEED said, it was fun just because it could be done. I wish I were a welder so I could have done it all but I employed some local TIG guys so it all worked well. The real thing. New ones Testing on my car.
@VOETOM That VOE configuration gives me some ideas I'm going to try. Can you tell me what the vacuum canisters are from? Hidden headlights?
Ebbspeed, you and I are both local to KC, and I have some smaller ones around. How much vacuum you have on the vehicle you want to try them on? I can loan you one to try. See the image, below. Those are mid 60s under dash GM actuators they pulled off the shelf for the VOE project originally (I was told). Tom
Great tech!! I don't get all the naysayers, I dig that a guy can build something with his own hands and not buy something. I have fun going down to my shop and fabbing up parts that I could go buy(I have more time than money). Well done Ebbsspeed!
I may take you up on that when I get ready to do some experimenting, but probably not going to be making any more until later in the spring. I'll be in touch, thanks!
Somehow I just came across this now even though you referenced my header build in your initial post. Nice work! That hemi in the video sounds great!