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etlsport
10/23/2007, 07:26 PM
looks like i may get my hands on a new pv2... i want to get as much out of it as i can.. what have people done with it to get the power gains to a maximum? I've got a green performance air filter from tone installed already... and i know that ill be installing a resonator after the pv2 to bring the noise down a little bit... but is it worth getting new pipes bent to step up to 2.5" new routing paths? basically im looking to replicate the original pv catback system which ive heard gave substantial power gains.. so what did that consist of?

johnnyapollo
10/23/2007, 08:04 PM
I have the cat-back PV1 (purchased as part of the group by from Powervault/John Finnell) - it's a mandrel-bent SS tube extending from the back of the exhaust to pretty much the same shape as the existing VX exhaust - it even has the rear exhaust hanger so it's a direct bolt-up. The front flange is short but ends right where the crossmember and rear of the cat flange lie. It's not complicated and shouldn't be hard to mock-up. If you know someone who can bend tubing you can have the old removed and a new following the same pattern. Make sure you add a hanger to the front to support the weight as there were some instances of a broken exhaust manifold due to the stress (may have only been with the heavier PV1 though) - the original VX muffler bolts directly to the frame and you want to get that stress off - also if you don't have a hanger the front flange can clatter against the crossmember. I'll try to get you some pics this weekend if no one else has any.

FYI, the resonating tip actually hurts HP a little (supposedly) by constricting the exit tube - when Dave and I had our setups dynoed the sound was noticeably different - the guy doing to dyno asked about it. Now that I've got the SC on there I'm noticeing both a louder exhaust sound and also a "sucking" sound from the CAI (it vents to the fender hole so it's really loud with the window down).

-- John

etlsport
10/23/2007, 08:28 PM
sweet.. thanks for the hanging tips.... is it 2.25" like the stock pipe.. or is it 2.5"?

johnnyapollo
10/24/2007, 09:34 AM
I'm not sure of the diameter - I'll take some measurements this weekend too.

-- John

etlsport
10/25/2007, 06:29 AM
after more research im getting a little nervous about the volume of the pv2.. so trying to figure out what pipe configuration would quiet it down a bit while without losing too much of the power gain..

anyone know if larger pipes from the cats will help to decrease resonance?

and am i correct in thinking that a longer tail pipe will help to cut sound down.. also thinking resonators.. kenny, if you see this how do you like your resonators? any info on them would be awesome!

Kenny
10/25/2007, 03:10 PM
after more research im getting a little nervous about the volume of the pv2.. so trying to figure out what pipe configuration would quiet it down a bit while without losing too much of the power gain..

anyone know if larger pipes from the cats will help to decrease resonance?

and am i correct in thinking that a longer tail pipe will help to cut sound down.. also thinking resonators.. kenny, if you see this how do you like your resonators? any info on them would be awesome!


Smaller pipes will reduce sound ~2" or less, but at the cost of back pressure and some power loss. 2.5" is probably preferred, 2.25" is good too with little power loss from 2.5". 3" is just too big. At least with 2.5", mandrel bent pipes probably aren't going to make a performance difference. Just cool to say you have them....:rolleyes:

the resonators are awsome, they did the job of taking out the resonance and left some growl, still loud mind you but no longer embarrassing. Mine were just 2.5" dia. x 10" blanks. Look for glasspacks form your local muffler shop that just weld in, mine were small due to dual exhaust and tight piping, but if you do one exhaust, you may fit a bigger one that will do more.

good luck!