I don't have anything against h-pipes per-se, I have one on my daily driver with full 3" exhaust, and it helps quiet it down a bit. My point is, it's counter-productive to getting a "period" sound.
Exactly my point also George. I get that on my roadster even tough it's an SBC engine, because I have an air gap manifold with no exhaust heat crossover passage.
I put Smithys on my 54 but i think i used the long ones,they are not as loud or "rappy" sounding as i had hoped for.
30 in. Smithy's on my 52 Chevy, split exhaust, stock 216. I thought it had a nice tone but you couldn't hear it in the car. I would have liked a little bit of tone in the car.
I put a set of Brockman Mellow Tone glasspacks on my stock 54 Olds and within 2 weeks replaced them with 30" Smithy's. The Brockmans are very well built but are LOUD. The Smithy's have the exact mellow sound I was looking for. If I were 16 instead of 70 I would have preferred the Brockmans.
For my 440 six pac powered 1930 Model A coupe, I built my own from 3" s.s tubing and 4" s.s. outer shell, 30" long. They are packed with s.s. wool. The entire exhaust is all s.s. 3" tubing after the Sanderson block hugger headers. I really didn't find it that difficult to make the mufflers, but I'm a welder by trade which helps. The slash cut ends of the system extend a good 10" past the bumpers and I get plenty of rumble inside of the car. I'm not having any luck downloading my photos so I have to do some homework as I'm tech challenged!
Those louvers won't create enough back pressure for you to notice, perforated tube cores are usually louder.
I am running Brockman Mellow Tones with Echo cans on my SBC with corvette style exhaust manifolds and 2" tube all the way back.
I had a pair of Porters on my 324 Olds powered roadster. As you know Porters use a stretched garage door spring for a straight through core. The id of the core is 1 5/16", yet inlet & outlet is 2". Excessive back pressure might be the result. I replaced these with $22 glass packs from Speedway. They sound great. I feel using insulated hangers will reduce droning. An h pipe will reduce that lovely rumble. In 1958 my friend Craig had a 48 Ford rag top with twin pipes. We jerked off the intake & put pennies in the heat riser passages.Then we removed the mufflers, replaced them with flex pipe from the Coast to Coast store. Man it sounded cool! We were in the driveway revving it up, enjoying the results of our hi tech mods. Craigs high strung mother came running out of the house yelling " Craig, Don't you dare drive that thing that way". Craig replied " stand back mother we're blasting off". Craig backed out of the driveway, shoved it in low, tires squealing . Away we went, heading to the local drive inn to show off. Well we were a little deflated when the local fuzz followed us there and gave Craig a $10 ticket for no mufflers. It was great to be a teen ager in the 50's Greg
Porters on my Cadillac 500. Standard length. https://www.jalopyjournal.com/forum.../4259581-43dc0b1920174a64a688b0e9e2a31cd9.mp4 I have Smitty’s on my 57 with a 351w and they seem ratty. But the exhaust is only finished to the rear wheels not all the way back. And they are old. Cadillac 500 Dual Porters by abe lugo posted Nov 1, 2020 at 8:05 PM
Engine master just tested the H pipe against the Y pipe on the dyno. The Y pipe produced a significant increase in hp. The 90 deg. intersection of the H pipe produced turbulence and backpressure. Use an X pipe for dual exhaust so the itersection is 45 deg. angle. This produces the best scavaging and the least amount of backpressure.
I have 27" Smithy's on my 57 Chevy and l like the mellow sound. They are not raspy and are really deep sounding at cruise. If you get on it there is more of a rumble but not annoying. Back in the 60s l had Walker Contenentals on my 56 Ford . They were louder and rapped when you got on them. Now l prefer the mellow sound of the Smithy's. I have an H pipe on my 69 el Camino with turbo mufflers and find the pipe quiets the mufflers somewhat. I do not have the stock crossover pipe on the 57. I guess it is all a matter of taste and age as to what sound you are looking for. Sent from my 9024W using The H.A.M.B. mobile app
I have used Smithy's on flatheads,Y-block and SBC and liked the sound in all 3,I did however put Porter's on a recent build SBC and was disappointed, sounds like aV-6.
What's worng with straight pipes all the way to the rear bumper? Low back pressure and the sound won't be bouncing up off the pavement. That lil mini SBF won't make a lot of racket anyway so it shouldn't be noisy at all! 6sally6
I'm running thrush glass packs behind my long tube headers. Its noisy and drones a lot. Looking for quieter ones.
I tried them all. The ones I liked best they don't make anymore.. The one's that came in a heavy gauge steel can are not made anymore except for the Porter.. The Porters I bought were very well made but the needed the spring opened up more. I may be wrong but when the spring isn't open the sound couldn't get to the steel packing.. Also the ones with glass packing seem to sound better. The photo is an old Douglass Super Sport muffler. I had two sets of these and they sounded great.
Mufflers are basically frequency filters. The glass cuts down high frequencies but is basically transparent to low frequencies, so you hear a low rumble (assuming the engine produces it to begin with). The steel wool doesn't do much of anything compared to what the glass does, so the exhaust will have more high frequency content and sound harsher. The best set up is to use a thin layer of stainless steel wool over the perf tube or spring or whatever, and pack the rest with glass. Then the stainless is only there to keep the glass from getting blown out.