obZidian

iTrader: (2)

I had just finished reading an article, very, very interesting; form poular hot rodding and it descrided the fundamental issues when designing a low noise, zero hp loss exhaust system.

In the article, it described using a pressure wave termination box or a resonator box.....

wat exactly is this thing?
Where can i find more info on getting on?
Also, is the resonator in my loudmouth the samething?

i found this very interesting and just wanted to see if anyone had any further info from experience or literature that would be interesting to know..

thanks

obZidian

iTrader: (2)

anyone?

obZidian

iTrader: (2)

doh!!!

no one has heard of this?

DaddySS

A pressure wave termination box is part of an exhaust system that opens up the exhaust to "release" the pressure and velocity of the exhaust and makes the engine think that's where the exhaust ends. It can be a hollow box, a larger diameter section of pipe etc. A resonator is just another name for the same thing. The idea is that once you have tuned your primaries, collectors, secondaries, etc. if you open the system with a pressure wave box you make the rest of the system "invisible" to the engine - so no reflected waves, etc. Otherwise the next component in the system - more pipe, a muffler, etc. appears to the engine - and the work you've put into tuning the lengths - as more pipe and therefor affects your tune.

More power!

David Vizard goes into quite a bit of detail on "termination boxes" in his book "how to build a small block Chevy on a budget" or something like that.

The terminator box is basically a hollowed out muffler. A RACING Flowmaster single chamber muffler (I know everyone hates Flowmaster, but it is just an example with a big empty area inside it) placed after the header collectors will effectively tune the length of the collector. Longer collectors (18-24") tune for more mid-range torque while shorter collectors tune for high-rpm torque (5000+).

The terminator box gives the exhaust pulses somewhere to expand, which then causes a slight vacuum. The slight vacuum draws more exhaust out of the cylinders during the exhaust stroke and more importantly -- with a cam with lots of overlap -- draws more fuel/air in during the intake stroke.

scifone

is that the same thing as the mac prochamber?

Wnts2Go10O

iTrader: (12)

no, the mac prochamber is a balance tube thats a cross betwen an x-h-pipe and aparently makes more power or somethin like tht

obZidian

iTrader: (2)

so the resonator in my loudmouth is something like a pressure box termination box.....

More power!

Yes, a resonator can act like a marginally effective pressure wave termination box, but isn't it at the very end of your exhaust? It will not have any effect back there. They need to be near the exhaust manifolds to have the desired effect.

obZidian

iTrader: (2)

also, in the article written by David Vizard, a set of cats act like a termination box. Could the combination of the two , reso/cats (high flow though) act together like a termination box.

Ideally, this is wat im shutting for. I would like to maximize my exhaust system the way he described but using as much of the current system i have now. I would like to remian witht he y-pipe at least, no duals for me......

does anyone know where i can get a pressure wave termination box or wat i might need to fabricate one?

thanks again
Angel

Dustin Butts

iTrader: (5)

I was wondering about this too. I never could quite understand what size, in cubic inches or volume, that the box needs to be. The best I could make out from that one diagram was that the box needs to be the same cubic inches as the engine displacement? So I guess if you run two boxes(for true duals) each box should be half the displacement of your engine?

So a 4"x10" Flowmaster 9" long would yield 360ci....etc..correct?

obZidian

iTrader: (2)

thats crazy!!

im ot moking you in the slightest but how am i suppose to fit that (or something larger since of my 408) in the current exhaust.

i think im about given up on the termination box.

my goal is to keep the reso or swap for a borla, then install two high flow chamber mufflers in both tailpipes. I know it might be a bit over kill, but it might just work if i can get some really highflowing mufflers like a gmmg style aka sweet thunders, stainless works., etc....

wat do ya'll think?

LS1Maniac

Instead of having an I-Pipe you could just use a bunch of bullet mufflers. It would take probably 3 of them to run the length of the I-Pipe. Then use two more bullet mufflers right before the tips.

Dustin Butts

iTrader: (5)

I know what you mean. I'm also not sure about that diagram for the termination box either. We may not need something that large. Space is definitely a limiting factor for these cars also.
I plan on doing some open header/collector length tests for max HP and then try to come up with a fairly quiet low loss exhaust.

obZidian

iTrader: (2)

how about one long chambered muffler (gmmg style) in the I-pipe and the two bullets in the tailpipes? it should work the same as your idea and i figured it should be easier to install.

do you think that this many mufflers might choke the motor some, even thought they are straight through race mufflers?

obZidian

iTrader: (2)

keeps all tune dude, i would like to see your results.....

yeah, space is big concern when designing anything that goes anywhere in these cars. I was surprised to see how much my stock pipes hit when i was on stock ride height. O'well, keep us tunes and im gonna through so ideas around to see wat ya'll think...

thanks