I thought I saw in another thread a while back that some Injen true dual exhaust owners had a custom h-pipe installed, bringing back some of the distinctive exhaust sound of the Z / G. Supposedly an H-pipe is also the ideal setup for N/A, something about mixing the exhaust gases to increase torque. Is this correct? I searched but couldn't find any info.

Any input would be appreciated.

 

Mixing exhaust gasses increases torque? That's a new one on me.

 

Equalizing pressure to create 'gas scavanging'. I don't buy that theory. Infact i read an article in some engineering magazine that an H-pipe does nothing but make it sound more high pitched.
On a turbo car, the H pipe wouldn't do a damn thing. After the turbos, the flow of the gasses is linear and no longer dependant on the valves opening and closing.

K i read the article, the reason why true duels loose the stock Z sound is because teh camming in the car cause a gap where there is no gas relieased and there for its more like 2 3 cylinder engines rather than 1 6 clinder. The gap causes the pop pop ..pop pop sound. When you have a H pipe itll fill in the gaps and ull have a more ricey sound, kinda like the stock Z sound.

Further read another article :-D
Larger diameter piping allow gasses to escape the cylinder faster, yet at a lower pressure. A perfect abdiatic combustion would mean that the pressure of exhaust is equal to the pressure of the intake gas, however, since its not perfect, there is some torque lost. By increasing the diameter, its further worsened and slight more torque is lost. On a turbo charged car, pressures are 3-4 times te intake pressure, and back pressure causes ineffeciency, high temperatures, resistance on turbo vanes ect. All in all, the largest diameter piping in either case is best

 

Thanks for the explanation plumpzz, that was very helpful.

So in theory then, installing an H-pipe into a true dual exhaust system would salvage some of the higher-pitched unique Z tones, and well as raising the overall pitch of the exhaust? I'm very tempted to try it... I just installed the SES that I purchased from a fellow forum member and love the exhaust, but also miss the unique sound the stock Z / G35 have...

I wish someone with some experience on this matter could chime in... I know I've seen in past threads that someone installed an H-pipe on their Injen SES... speak up please!!