The Stovebolt Site Forums The Shop Area Engine Shop Question about "glasspack" muffler.

Building my exhaust now and decided to go with a straight-through cylindrical muffler. Looking inside the inner pipe has louver-like openings all facing the same direction but there is nothing on the thing indicating if the open side of these louvers face the engine or the tailpipe.

What direction do the open end of these louvers face? Or does it even matter?

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It depends on whether you want it loud, or obnoxiously loud, I guess. Facing the openings toward the exhaust stream will result in slightly higher back pressure, and maybe a little quieter operation. I prefer to use a conventional chambered muffler and increase the pipe diameter one size to reduce back pressure. I've got the old-fashioned idea that a muffler is supposed to make the exhaust note quiet enough for me to think, and avoid a noise-induced headache, though. People with irritatingly loud pipes need to paint a big target somewhere on their vehicle so the rest of the world can get a better aiming point!
Jerry

I have Smitty's on mine and if you look into the end marked "inlet" the louvers are facing away from you.

I beg your pardon... If you're addressing your angst toward me I'd suggest you check out just how loud a stock 235 is through a single 2.5 inch glass pack muffler for a better idea of exactly what we're talking about here.

Lighten up.

You didn't say whether it was a 6 or v-8. On my v-8's with duals I specify 2 in. pipes & 30 in. glasspacks. They have a little rumble in back but practically no noise inside while you are driving.

I have 22" packs on my 235 and it is only obnoxious if you want it to be, if you really lay into the pedal. Otherwise it has a real good sound to it. Those were also the longest glasspacks the muffler shop had.

.... well you guys would hate me! I ran STRAIGHT pipes on my 37 with the 350 for about 6 or 7 years. Man, I love'em. However, it was not real bad unless I WANTED to make racket and then look out!!! But, OLD AGE has slowed me down. I now run a set of original Smitty's and they are QUITE.... well, I'm burning them out pretty good.

But there is nothing better, in my opinion, than listening to a beefed up engine "counting them off" as it sits there idling. Maybe thats why I love racing so much and also why I'm half or 3/4 deaf!! ..and listening to my brother run one on the dyno. Wow, what a rush!

To each his own. I just try not to "infringe" on others going around town.

I sure understand about that OLD AGE thing Chipmunk. I love to hear anything "count them off" at idle as you say from a John Deere A, a Harley or even a steam locomotive. I put some Edelebrock mufflers on my 57' BelAir and man o' man is it ever loud. Not at all what I want so they have to go. On the other hand my 53' 235 pickup has twin glasspacks approx. 20" or so and it is way too quite.

Us old guys sure are hard to please aren't we?

Happy Thanksgiving everyone.

I'm changing my 235 over to a Corvette manifold with a pair of 22" Smithy's. I plan to finish it this weekend. I had a stock muffler on the stock exhaust manifold. The stock muffler was extremely quiet except under heavy load, where it worked its way up to quiet. Due to an ignition problem I blew that muffler up. I was very surprised by the lack of content when I looked at the insides (pic). I think the engine characteristics have a lot to do with the sound as well. My 235 is stock in a 55.1 3100, so it has virtually no compression (7:1?) and a cam that is so conservative it would make Rush Limbaugh feel embarrassed. One of the guys in my local Inliners chapter has a 235 in his 53 with higher compression and a mild cam from Patrick's. Totally different exhaust note. It sounds like it wants out.

regards,
Leon

I like these mufflers. http://www.vanpeltsales.com/FH_web/flathead_speed-mellowtone.htm I think steel pack sounds good on a 6cy and a glass pack on a v8. It reminds me of how they sounded 50 years ago.

http://smg.photobucket.com/albums/v228/Avette4me/video/?action=view&current=20091126133941.flv

Try Brockman Mellowtone, they've been making glasspacks for a long time and can direct you to the right size and packing for the sound you want.

Ray