Tom_K

OK so maybe I have too much free time and some basic fabrication tools.

I am adding side headers and pipes to my 68 427. (Dougs headers)
For inserts the quiet ones are way to restrictive and the non restrictive are too load...

So my idea is to fabricate my own, It is a simple glass pack design and should work.

I can use a 2.5 or 3" tube and run it almost the entire length of he pipe.


Thoughts??

pws69

Having [also] spent a stupid amount of time experimenting with various exhaust variations, I'm afraid you will end up with the equivalent of " non restrictive are too load... " - with a probable buffering of some of the high note "raspiness" - as a result of the "packing".
I found I always need some type of baffling to calm the roar down and baffling is much trickier because of the impact on performance. There's much more to it!
Those are my thoughts, for whatever they're worth.

69427

I encourage you to make your own. It's a great learning/fabricating experience (I fabricated the mufflers for both my Corvettes and my garden tractor).

Just an item for thought. You could also make a portion of the middle of your insert into an expansion chamber. That would probably help cut/quiet the noise volume pulses (at the 8&4 and 5&7 exhaust valve openings) that are part of life with Chevy engines.

What ever you do, post pictures.

Richard454

Mines a combo- straight pipe and/or muffler. Using electric cut-outs to go between straight unmuffled to full muffler-

I made my own 20" long glasspac type muffler- as from what I have read after 20" the noise reduction is minimal.

perfed SS metal- insinkerator (SS steel) garbage disposal rings hold it together-








I used stainless steel tie wraps- Summit Racing sells them

I wrapped it with exhaust tape- to keep the fiberglass from blowing out-


Here's the cut out design-





Used V-bands to clamp together- and can change out insert if I don't get enough noise reduction

metal tech

I've had the same thought/idea about making my own muffler for sidepipes. My sticking point is the perforated tubing, can't find a good source for 2.5 or 3" 304 SS tubing. I can find flat material but would need a shop to roll it and then weld the seam. Anybody want to share their source?

suprspooky

If there is enough interest, I have a friend with a shop that specializes in laser tube cutting. I will try to get an idea of what he'd charge me to do a small batch of perfed tubes (say 3" x 36" 16g Stainless, $33 on Amazon) using 5mm and 10mm dia. holes and maybe a combo of those sizes.

suprspooky

Richard, I love the electric baffle idea (I've been torn between reasonable sound and minimal HP loss). The quiet Side Pipe Hookers kill power when you are moving enough air to support 560ish crank HP and the Hooker high flows are almost painful (I know,I'm getting soft). I will be using part of your idea on my Hooker Side Pipes (I needed one more Winter project )

Richard454

Thanks!!!

I can stop them somewhere in-between. I should have my engine up and running again in the next few weeks- and hopefully will do what I want them to. I didn't save the receipts for all the stainless I bought..,As I don't want to know!!!


I looked all over- I did find several dealers across the pond in England for selling it. I ended up just getting some sheets- tacked one side to a piece of 4" tubing I had laying around. Put on some gloves - and was able to make it work.

https://www.ebay.com/sch/m.html?_ssn...rated&_sacat=0

http://www.ebaystores.com/Myriad-Exh..._sid=131329888

caskiguy

You do amazing stuff Richard.