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Hi everyone, I have a 1936 Chevy pickup w/235 engine; I installed headers & 30" Smittie mufflers, I don't like the sound they are producing, I want a growl w/a rumble ( deep mellow tone with the rapping. I'm now getting more of a Woof Woof sound. I used to have a friend in school that had a 49 Chevy & when he stepped on the gas the mufflers would rattle the windows. Anyone out there that can tell me the correct mufflers to get for the sound that I want? All help is greatly appreciated.

Where you place the mufflers in the system has a lot to do with the sound. Up front has a different sound than towards the rear. I'm sure you will receive your answer soon.

I know if you put them closer to the engine, you will get a horrid obnoxious racket. I ended up putting a second set of 18" universal magnaflow mufflers after the rearend, so I actually have 4 mufflers now. I think if you put them as far back as possible you will get the closest to what you are after. You have confirmed the fond memories people have of the "distinctive 6 cylinder sound" is of the blowing the windows out of neighbors houses type, thinking it was really cool when you were 16 years old sort of thing. But now when you are old, it is just plain annoying. But to answer the question of which muffler to use, the 30" smitty's are the muffler you want. If you want the authentic sound. I'm just not sure memories always coincide with the reality.

Your friend possibly had no muffler(s) at all, straight pipe. If you do an all day trip it's going to get old real quick in that little, hollow '36 cab. You can also bring along hearing protection.

I have 30" glasspacks and installed an 'x-pipe' before the mufflers, very mellow sound, then again I do a few 1k trips each year.

I had the same experience as brokenhead with my Suburban. I used generic glaspacs close to the firewall. The sound was obnoxious at highway speeds. I added Walker resonators aft of the axle and now have the sound I was looking for. It has the rap going through the gears then mellows out on the highway.

Where exactly does your exhaust exit the truck? My experience is that even with glasspacks, exiting the exhaust at the very back of the vehicle, and pointing straight back, will keep the overwhelming majority of the noise out of the cab when at highway speed, yet still give you the "performance" note when accelerating.

You could have them on backwards , It will make a big difference ..

Good point,glasspacks by nature only work correctly in one direction.
We used to deliberately fit them 'back to front' in turbocharged VW bugs,it helped airflow but didn't do a lot to reduce sound levels,freed up a few extra HP though.

Not always true, it depends on the glasspack design. Glasspacks either have holes or they have louvers on the inside pipe. Some designs have directional louvers which dictate exhaust flow directions and some don't.

There are several other factors involved in terms of the overall total flow capacity & muffling capacity / sound of a glasspack. This has to do with how sound is directed into the fiberglass damping material. Higher flow mufflers simply have a multitude of holes drilled into a smooth bore center core. While this increases total flow capacity, the ability to muffle the sound passing through the core is reduced. The smoother bore of such a design does little to create turbulence and / or direct the sound waves into the fiberglass damping material, resulting in less muffling capacity. Walker / Thrush / Dynomax & Magnaflow brand glasspacks make use of this type of high flow core design.

Most other glasspack mufflers utilize perforated louvers punched into the center core. This can adversely affect total flow capacity. How much it lowers total flow capacity will vary depending on how far the louvers protrude into the airstream and which direction the louvers face. The turbulence created by the perforated louvers therefore achieves greater muffling capacity at the expense of total volume of air flow. The more turbulence created, the greater the muffling & less total air flow / power production capacity. Depending on the directionality of the louvers, once can choose between slightly higher flow capacity or slightly greater muffling. This lower flow but slightly quieter design approach is used in most all glasspack mufflers, including Cherry Bomb brand glasspack mufflers.

http://en.wikipedia.org/wiki/Glasspack

Like I said they could be on backwards....

backwards would be a matter of preference for many people, I just think the sound we all remember from the past isn't the pleasant tone we recall. I just went to a drag race for the first time in 30 years, now maybe they weren't as loud back then, but for the love of mike, top fuel nowadays is absolutely mind boggling. Nothing like I remember.

bebop40 said he didn't like the sound , so it wouldn't cost anything to turn them around . I bought a set this year they was not marked inlet and outlet . And yes mine sound just like I remember 60 years ago ....I've got to get used to every time I put something on this forum somebody always wants to beat me up..
So I think I'll keep my opinion and what little knowledge I have to myself .... and just read ....

It's all good. I'm not "beating you up", just pointing out that it may make no difference in tone by flipping the mufflers around.

I emailed Speedway and asked if Smithy's internal louvers are directional. I'll post their response and then we'll all know for sure.

the smithy's are directional, and it will cost quite a bit to flip them around if they are welded in and you have to pay someone to do it.

Per email from Bill Emberton 08-08-2014, Street Rod Tech for Speedway Motors: "We pulled the muffler and the latest versions have an inlet arrow showing flow direction of the muffler."

...and the one's I bought 3 maybe 4 years ago also had the inlet marked.

It's always nice when you think you are so right , then do a little research and find out you was always wrong ...

HRJ,

Thanks for posting the information that you got back from manufacturer.

Always glad to help.

The best way u can help is not give out bad info.

HRJ, good info

Geeze, what are you all butt hurt about anyway?

If you go back and re-read my posts I stated some manufacturers have direction louvers and some don't, I was very clear about that.

So I did the research to help the guy that posted to find out the facts for the specific mufflers he had.

That would be great, maybe you could be one of those guys that says what he means, and does what he says?

That would be great!

John

In the words of Seargent Hulka in the movie Stripes.....Lighten up Francis.

LOL Hot Rod John you removed the post, or had someone do it for you, where you said it made no difference ... Like I said to start with, it will make a difference , and I don't have to ask anybody because I was sure to start with ,. just because you removed the post where you said it made no difference ,don't make you right ,. I wish you would do your research first before making your wrong statements .

In the words of Seargent Hulka in the movie Stripes.....Lighten up Francis.

Yeah, it's a conspiracy... Seriously? I didn't remove any posts and neither did anyone else on my behalf.... you are indeed a real piece of work.

Yes you did or had it removed ... we both know that....

Easy now, it's just a forum. Don't let this morph into the cam break in oil thing. Move on.

Hidiy bebop-

First off- The only mufflers I know anything about screw on to the ends of firearms. When I was in the market for them, I went to somewhere that had them in action and just listened. That is how I knew which ones I liked.

I would go to an antique car show or cruise gathering, and single out the growling rumble sound you're looking for- I'm fairly confident the owner will be glad to tell you all about it. This is just what I would do, because it is very difficult to describe things online that are based on the observers perception.

Another member recently posted a video in a forum of his newly installed exhaust sound, but I could not find it when I looked for you. As soon as I find the video- I'll send it to you.

Brad

Nevermind on the videos. Both the first and the second time you have asked this same question the guys posted you videos (that I was looking for), and some good advice.

It 'sounds' like the sound you're after is very elusive & you have done a lot of hard work to find it.

Would it be possible to post a video of your 235's muffler sound that you don't like? My '55 truck looks like the rats left their seat cushion buffet for a metal desert all up and down the tailpipe and muffler. Since I'll be replacing it, video or audio of your current setup would be great for a reference. It would also let everyone hear your engine's sound & recommend adjustments.

Brad

Just did a new sxhaust system , front to back , on my 54 pickup. Custom built 2" pipe with a glass pack.muffler was installed in the location as a stock muffler would go. It has a nice sound , alttle louder than a stock muffler and not obnoxious at all. The design of the new systym it pretty much the same as stock, but as mentioned with2" pipe and the tail pipe was changed a bit..just a plug for those who advocate putting mufflers in the stock location, no matter what kind. It works well.