lol makes me think about reconsidering swapping for my hfc's for art pipes

 

Can honestly say i don't know what is being referred to with the sound at those revs, no problems here and never heard it on a vid. Perhaps something specific with the rest of the exhaust?

As for the smell, that's down to the engine/tune, unless you're particularly sensitive to non catted cars. Seems cats have been around so long here that people just expect the smell to be a certain way.

I chose the XYZ pipe with the HFC, partly for the smell and partly for trying to be slightly tree hugging. I have to say though, currently running with the resonator module and the smell is barely noticeable.

PS, here's the power and torque changes compared to HFC's, obviously over stock cats it will be even more.
Also note that normal test pipes loose to the stock setup in the low revs, the ART pipes *gain*.

 

Those graphs are versus standard test pipes. Power is lost down low with tps because there is no cat honeycomb to slow down flow. Torque is gained from a higher resistance to flow.

Honestly there is no avoiding rasp on our motors with stock headers. The pulses are merged in a way that multiplies the warble sound, and those pulses become cracking rasp when resonators are removed. Even shorties don't fully escape the wap wap wap. :P

 

So long tube headers greatly decrease rasp?

 

but the gaskets that came with the FI hfc were correct right?

 

Yes, they were the 2.50" gaskets. My mistake was going to Nissan and buying OE gaskets in the beginning not knowing they were the wrong size....live and learn, measure twice install once.
Gary

 

Have an appointment with Seb Wednesday AM to find out why my front suspension makes so much flipin noise. Lower control arms and shocks replaced made no difference at a cost of $1700=. The bushings were bad, not sure now if the shocks were or not. Find out Wed....Gary

 

Seb and his mechanic went thru my whole suspension, drove SLICK around the block a couple times trying to pin point noises. But it was Seb that discovered my rear swaybar endlink almost dangling, yea that loose. A couple wrenches and some Loctite red will keep it tight for a long time. Always glad when I leave SpecialtyZ knowing the job was done right and no more suspension noise....Gary