Any exhaust technology engineers out there?

**SSPORT** · 03-01-2006, 09:04 AM

I have an exhaust mod in mind, but am not sure that it would help or be a waste of time. Right now, I have the following exhaust setup on my breathing-enhanced LS1 (air inflow mods = SLP cold air intake, LS1 Motorsports lid, MBA polished & descreened 75mm MAF, Shaner S2 TB, 1.85-1 rocker arms)

Exhaust = JBA shorty headers, SLP Y-Pipe, SLP original Loudmouth, with twin 4-inch diameterSupertrapp mufflers (to reduce that damned resonance!) on the ends.

Since the Camaro doesn't have a true dual exhaust system and I like simplicity, I was thinking of cutting off the section at the rear where it goes from a 3-inch pipe to twin 2.5-inch pipes, and welding on a 3-inch section to continue the exhaust over the axle, then putting a single polished S/S tip on the end (such as a Summit, or Megs, or Hedman Big Wazoo) exiting on the passenger side as one big, single exhaust.

The idea is to continue the 3-inch exhaust all the way back, making as straight an exhaust path as possible and eliminating (1) the reduction from 3 inches to 2.5 inches at the rear and (2) the curvature necessary to create the "dual exhaust" look.

It then occurred to me that when the 3-inch pipe coming out of the resonator goes into the "collector" that splits it into twin 2.5-inch tubes, the effective diameter is increased to 5 inches, and that to continue a 3 inch exhaust tube at the rear might actually restrict the flow rather than increase it.

So at this point, I admit "I'm not a gas flow engineer, I just play one on TV", and solicit advice from anyone who actually is qualified to comment!

Thanks guys...

**third_shift|studios** · 03-01-2006, 11:15 AM

as long as it doesn't look like this:

**jmhvenom** · 03-01-2006, 12:18 PM

Hey, sitting here at work lol and I guess being a Mechanical engineer might qualify me for this lol. But, you are going to have less bends and also not going to be splitting the airflow, and also less length. If anything it might help a little, but its not going to hurt it.

**SSPORT** · 03-01-2006, 12:44 PM

Originally Posted by dipherentdesign

as long as it doesn't look like this:

Uh, yeah, you got that right. Looks like the owner of this... thing... is massively unclear on the concept of HAVING horsepower rather than PRETENDING to have horsepower. Well, seeing as this photo is from AutoTrader.com, I hope he gets a good price, so he can then buy the Honda Civic of his dreams.

**MysticZ28** · 03-01-2006, 06:26 PM

Originally Posted by SSPORT

It then occurred to me that when the 3-inch pipe coming out of the resonator goes into the "collector" that splits it into twin 2.5-inch tubes, the effective diameter is increased to 5 inches, and that to continue a 3 inch exhaust tube at the rear might actually restrict the flow rather than increase it.

So at this point, I admit "I'm not a gas flow engineer, I just play one on TV", and solicit advice from anyone who actually is qualified to comment!

Thanks guys...

It's not diameter but actual flow area ... twin 2.5 will equal about the same a single 3.5 pipe. You are increasing the restriction somewhat by going to a single 3" exit.

All in all though, as far as gains probably not much difference one way or the other. More of an appearance asthetic preference on your part.

**Liquifire** · 03-02-2006, 03:25 AM

performance wise it would not matter unless you have a very high HP vehicle........there are not many vehicles that actually require the 3 inch or larger exhaust pipes. You are right that in theory it would restrict the flow more than the twin 2.5's going in to it but you should keep in mind that you are not coming close to maximizing the maximum flow potential of your collectors. If you want to increase your flow go to long tube headers. You need to get well above the 500 HP range before needing anything bigger than 3" exhaust. Having a larger exhaust does not mean better flow unless you are past the maximum flow potential of what you currently have.....your "bottleneck" for this system is your muffler and having shorties instead of LT's ...............imo........fwiw.

**Liquifire** · 03-02-2006, 03:26 AM

Originally Posted by dipherentdesign

as long as it doesn't look like this:

actually, I kind of like the exhaust tips.........but the wing has got to go.

**SSPORT** · 03-02-2006, 04:30 AM

Originally Posted by Liquifire

performance wise it would not matter unless you have a very high HP vehicle........there are not many vehicles that actually require the 3 inch or larger exhaust pipes. You are right that in theory it would restrict the flow more than the twin 2.5's going in to it but you should keep in mind that you are not coming close to maximizing the maximum flow potential of your collectors. If you want to increase your flow go to long tube headers. You need to get well above the 500 HP range before needing anything bigger than 3" exhaust. Having a larger exhaust does not mean better flow unless you are past the maximum flow potential of what you currently have.....your "bottleneck" for this system is your muffler and having shorties instead of LT's ...............imo........fwiw.

Not to mention that I have stock cats! And not to mention that I would have to cut off two S/S SuperTrapps that cost me $160 each, plus the muffler shop cost I paid to remove the SLP tips and weld the 'Trapps on. Hmmmmm...