Hi,

My Z is way too loud for some tracks...120dB at WOT...

PPE long tube headers, Motordyne Xyz, Power Agency Ti Single...

How can i quieter it without losing performance ? I thought of Apexi active tail silencer, but it seems it is as loud at WOT....

I'm afraid a standard silencer will make loose a lot of power....I have a quieter catback but i love the Power Agency sound....But since i put long tubes headers to gain horsepower i don't want to loose hp with a silencer..

 

you could try adding a cat to the xyz

 

1. XYZ HFC Attachment
2. Weld a resonator into your midpipe (no clue how it'll affect overall sound, but will quiet down)
3. Exhaust Control Valve (eBay the correct size depending on your flange/piping size, controllable by a lever, Apexi and another brand make them). Have read reviews however that sometimes the valve MAY get stuck.

 

PPE can make u a ypipe with highflow cats. Think it's 500$ or something and then u could sell the motordyne ypipe

 

I have the HFC attachment for my Motordyne XYZ. I tested it before having the Ppe headers and i didn't seem to lower a lot the sound volume...

I will try again, but i don't really believe it will be sufficient...And it will make me loose power....

120dB is with the resonator on XYZ

 

Just find an exhaust that pairs well with the PPE's both sound-wise and power-wise.

I liked the PPE's + TDX2, was loud but not overly loud, and made kickass power. You can buy them with HFC's built into the mid-pipes too (order direct if so).

 

Holy crap, thats loud lol. Dual exhausts are usually quieter and something with resonators like the greddy should help.

 

Sell ur exhaust to me agency power is way to loud

 

Cut your exhaust and add V band flanges to the muffler. Then order a 3 inch chambered muffler, put a flange on it and install it when you need to run at a track with low sound levels

 

Tony from motordyne will even tell you the HFC module will not make it quieter, it just cleans up the gas smell. I'm running in to the same issue with my Tomei, looking to sell it now that the Z is a daily driver again.

 

You know the 5whp you lose from changing your catback is really negligible on the track.. unless you're on a straight or unless you are drag racing

 

yoh u got a tomei expreme single ? inbox if u tryna ssell it

 

I tried with the HFC attachment : no changes in sound. Perhaps more noisy than the resonator...

 

Will investigate that option