Exhaust Tuning

[Camar068]

Anyone have any good links/reading material on the subject? I've read a few but they have all been so vague as in at what time do you want back pressure, resonant frequency and such other terms.

There's got to be a way to measure all these "terms" and fine tune your exhaust and/or make it a "real" dual exhaust where it changes (by opening a valve to another system/chamber) itself from one configuration to another depending on throttle/flow etc.

LOL last paragraph way outside the box (and way out of my expertise....don't know **** about exhaust). But with sensors these days, you would think it wouldn't be the "science" that it is.

Thanks In Advance
'Maro

 

[bucket]

The issue is there are way more opinions and rumors about exhaust flow than there are facts backed up by scientific studies.

And "real" dual exhaust is a dedicated pipe for each cylinder bank. You are describing dual mode exhaust, which is available on new Corvettes and Camaros.

 

[Camar068]

Thanks, didn't know they'd done it. I typed it that way in an attempt to describe it lol.

 

[bucket]

I don't know what controls it exactly, but it's electric and tied to the PCM. I don't know if it's simply the TPS that operates it or if it bases it off of engine load too. But I do know that there's a fuse you can pull out to make it bypass the baffled part of the mufflers all the time. Chevy has been using the setup for several years now.

 

[Camar068]

After reading your post, it appears there is a switch in the vehicle that you manually switch. The exhaust cut-out valves aren't terribly priced either. Of course the cheaper they are, the more they leak when closed.

For what I'm thinking you would need a valve that is quick to open/close. Be nice if it was variable and quick then just control it with a tps signal. That way it would start to open prior to downshifting in an automatic.

Thanks again, gives me something to think about.

 

[Rusty Nail]

In reality land, tubing diameter and collector length.

That's basically all you need to know.

Chances are 1&5/8 primaries are too big.

 

[bucket]

After reading your post, it appears there is a switch in the vehicle that you manually switch. The exhaust cut-out valves aren't terribly priced either. Of course the cheaper they are, the more they leak when closed.

For what I'm thinking you would need a valve that is quick to open/close. Be nice if it was variable and quick then just control it with a tps signal. That way it would start to open prior to downshifting in an automatic.

Thanks again, gives me something to think about.

For aftermarket cutouts, yes. You just flip a switch and they dump the exhaust. But the factory dual mode exhaust that Chevy uses still comes out the back, and the valving is done automatically.

 

[Camar068]

Right, I was thinking if I wanted to spend the money on it I could find a signal to control it when I do the LS swap.

Doubt it will happen, I've got other things to spend money on....other truck parts, gearing change, oil cooler, guns, that crew cab I want.....LOL.