VE SV6 exhaust question for the gurus

[the_panther]

Have spent a while trawling threads. Have had a fair crack at the massive VE exhaust thread.
Picked up a SV6 cheap recently. Was dumped on its guts so was unable to see that it had a centre muffler delete. (garbage job also.)
There was a GTS centre available on gumtree but I've just missed it by minutes. annoyed.
Picked up a set of extractors for under 100 so that's good.
So I'm needing a new centre for RWC. What's in there will never pass.
Got a used centre on ebay. Ill pick it up shortly, throw it in and get it through RWC.

So its got me thinking..
I'm going to need to do the standard cat re-weld to fit the extractors (flanges are rotated).
While I'm at it, Im thinking of chopping up the two exhausts and making a similar GTS centre.
Cut the second exhaust to get a spare set of resonators, weld them into the old system (the old system is neater) and have a dual resonator system.
Anyone done anything like this?
I'm also considering throwing a crossover in there, if so, before or after the first set of resonators?

I have seen some xover style pipes for sale, the reviews don't seem good, I cant afford a difillipino or whatever, I like the idea of staying with factory steel.

Thoughts on Extractors >Cats>xover>Resonators>resonators>AFM quad tips. Looking for free flowing sporty burble, minimal drone, keep it quiet.
I will eventually swap cats in future, 200-300 cpi. as expected.

Any exhaust guru care to chime in on the proposed system?

 

[the_panther]

Ok, so in waiting for a reply, I kept searching and have found that the exact system I'm planning is a 1:1 design of an off the shelf exhaust, albeit in 2.5"
So the system will work, has a good chance of being reasonable.
Off the shelf system is made by PCE part number: PCE518.1010
Image attached. rrp, 1600, sale price 790.

I'm going to build it.

 

[the_panther]

ended up picking this exact system up off a guy for under $300. its also sold by dandy exhausts i think for 700. sounds nice with afm muffler quad tips, little droney with the supplied mufflers. fits and flows great. paint near the cats is not handling the heat tho. fits well, the mid hangers have a protrusion that hits speedbumps with sssl kings. might grind it down next time its off..

 

[shane_3800]

ended up picking this exact system up off a guy for under $300. its also sold by dandy exhausts i think for 700. sounds nice with afm muffler quad tips, little droney with the supplied mufflers. fits and flows great. paint near the cats is not handling the heat tho. fits well, the mid hangers have a protrusion that hits speedbumps with sssl kings. might grind it down next time its off..

With your original question the more resonator the better.

When I built my 4cyl ute exhaust I had bad drone so I looked into it and found some good info on a Honda forum. Pretty much from what they're saying about their Honda's needing X amount of resonator a V6 commodore will need as many resonators you can fit under the car.
My 4cyl ute is running one hotdog and is a little drony so I need to add a second but I'm going to add one a different size to change the frequency.

 

[Not_An_Abba_Fan]

Rear mufflers on any aftermarket system tend to be the let down in terms of note. There are very few that actually sound good. Manta make some good ones, but expensive. Just keep the AFM mufflers on there. Not much you can do to reduce drone on a V6 with that system apart from the AFM mufflers. Don't fit a cross over, they sound like crap on a V6, unless you fit a proper X pipe.

 

[rtmpgt]

Rear mufflers on any aftermarket system tend to be the let down in terms of note. There are very few that actually sound good. Manta make some good ones, but expensive. Just keep the AFM mufflers on there. Not much you can do to reduce drone on a V6 with that system apart from the AFM mufflers. Don't fit a cross over, they sound like crap on a V6, unless you fit a proper X pipe.

This.

Never, ever delete any centre mufflers on the SV6 unless you want to play the fart trumpet orchestra down your street. Trust me, It sounds like arse, especially at low RPM. High RPM and High load, Low RPM it sounds alright if you're going for that Jap car sound, but don't ever expect any V6 to sound like a V8. You have two few cylinders for that.

My ute's got a VE SS Non-AFM Centre section with twin hotdogs instead of the factory twin muffler SV6 centre section and I got a nice increase in volume with no rasp. To be fair the thing you're trying to combat on the SV6 is raspiness. With a straight centre it sounded like absolute dogshit, with the V8 centres it's perfect in terms of tone, but it's kinda quiet. Not a bad thing, means you'll get less attention from the cops.

Mufflers reduce volume, resonators reduce rasp. A muffler uses baffles and/or glass to absorb large amounts of sound, but they do so across the entire sound spectrum. Meanwhile a resonator is simply a different kind of muffler. Usually a straight-through design with glass fibre material to absorb the harsh sounds that are caused by rasp. V8s sound nice when they flow freely but because of some of the design aspects of the HFV6 engine (firing order, crank pin angle, valve angle and the like) it doesn't sound as nice as other V6s when they flow freely (Talking the VQ37, Jaguar's V6 and the like)

My solution for drone (that annoying noise when you're cruising) as well is to use E1 (Vacuum actuated) HSV Bimodal mufflers and get it tapped into your engine's vacuum. I use a custom-made throttle body spacer with some NPT ports but if you're handy with a tap-and-die set you can always tap in some 1/8NPT ports into your IM at some point behind the throttle body to get them working. Sedans and Wagons are the worst for drone as the area above the exhaust is a plastic false floor which just leaks sound into the interior. Hence why you see all the J pipes and such out there for these cars.

if you're going custom, twin resonators and a cross will do you nicely imo. Use 2.25" section unless you intend on eventually going SC. 2.5"at the most is all you need for the V6. If you put a cross anywhere on your exhaust you want it as close to the engine as possible.

 

[harrop.senator]

The centre mufflers aren't really mufflers . They're a twin in/out resonator box. They're straight through perforated pipe with glass packing.

Could argue they're " straight through mufflers." But the body size in my opinion isn't large enough and won't do tooooooooo much more then having twin hotdogs in the same section.

I've go twin 2.5" mild on the Mrs wl. Pacemakers , cats , twin 9" hotdogs , centre mufflers and rear box.

It sounds pretty decent anywhere that's not 2700-3300 rpm.

I should have made some pie cuts and put the 15's in after the cats but I was being lazy and with how small the factory resonators are on vz it's cure it. It improved the sound ten fold. But still needs more resonator .

 

[Not_An_Abba_Fan]

I've go twin 2.5" mild on the Mrs wl. Pacemakers , cats , twin 9" hotdogs , centre mufflers and rear box.

You just used three different words to describe the same thing..."silencer".

 

[harrop.senator]

You just used three different words to describe the same thing..."silencer".

Yeah and it still sounds pretty horrid. Was just trying to explain just how many silencers were in the system and still isn't satisfactory.