Difillipo 3 inch vs Walkinshaw catback

[vc commodore]

I get stacks of comments as my MagnaFlow sounds pretty hot. But it's pretty loud and it can be a bit of the ear if you're cruising the city with the windows down. I wouldn't change it but man it's loud and if your in a multi story carpark it can be hard to really try to concentrate on squeezing into those tight car spaces. Funny thing is I never realised until the last couple of days that I really noticed it is loud as it is. I have never driven in Westfield or multi storey carpark, or in big city traffic with tall buildings around.

Loud PFFT.....I only heard it from a block away and I forgot my hearing aids....

 

[[paradox]]

US is funny I think over there it's go big or go home.

yep all about their 2" american racing headers
or kooks if you are cheap

 

[RevNev]

Having built exhausts and particularly race car exhausts and mufflers for 30 years, I can build and modify exhausts and mufflers pretty easily playing around in the shed. With my SSVR Ute (340 headers and piped cats), I changed the X-Pipe in the Maloo midpipe I got for it to stop the pipe ring, a tinny noise in the pressed X-pipe arrangement HSV use that's sounds like it's leaking under load. I did a proper (non-restrictive) X-Pipe with two 15-degree merge collectors welded together. The blend hole I reduced down to 1 7/8" to give the note more H-Pipe separation.

The hot dogs are 2.25" internally so I changed those for a couple of 2.5" resonators I made up and ram packed them with fibreglass.

At the rear, I chopped up the stock bimodals and reworked them Lukey style using a 2.25" inlet, centre chamber and twin 2" outlet ram packed with fibreglass. Retaining big (factory size) rear mufflers, it's probably on the quiet side with the bimodal valves open despite that it's catless with only two 12" long straight through resonators. I could probably delete the resonators altogether with muffling effect the big rear muffler cannisters provide.

When we're talking loud and droning, the aftermarket for some reason all want to run small rear mufflers and wonder why they drone. I'm yet to find one aftermarket manufacturer smart enough to go big in the rear mufflers and adjust noise level in the midpipe.

Droneless exhausts isn't as hard to do as people make out

Drone can be easily tuned out with large quality mufflers and/or resonators if required

Absolutely correct!

 

[Ginger Beer]

Having built exhausts and particularly race car exhausts and mufflers for 30 years, I can build and modify exhausts and mufflers pretty easily playing around in the shed. With my SSVR Ute (340 headers and piped cats), I changed the X-Pipe in the Maloo midpipe I got for it to stop the pipe ring, a tinny noise in the pressed X-pipe arrangement HSV use that's sounds like it's leaking under load. I did a proper (non-restrictive) X-Pipe with two 15-degree merge collectors welded together. The blend hole I reduced down to 1 7/8" to give the note more H-Pipe separation.

The hot dogs are 2.25" internally so I changed those for a couple of 2.5" resonators I made up and ram packed them with fibreglass.

At the rear, I chopped up the stock bimodals and reworked them Lukey style using a 2.25" inlet, centre chamber and twin 2" outlet ram packed with fibreglass. Retaining big (factory size) rear mufflers, it's probably on the quiet side with the bimodal valves open despite that it's catless with only two 12" long straight through resonators. I could probably delete the resonators altogether with muffling effect the big rear muffler cannisters provide.

When we're talking loud and droning, the aftermarket for some reason all want to run small rear mufflers and wonder why they drone. I'm yet to find one aftermarket manufacturer smart enough to go big in the rear mufflers and adjust noise level in the midpipe.


Absolutely correct!

The buy of the shelf stuff seems to be made to cost, more so made to perform and sound good, thin walled, small bodied, packed loose if your lucky, packed with nothing if your not

From my experience people always use to have custom exhausts made with the number and size of mufflers and resonators optional, I remember on many occasions getting an exhaust built, then tuning it over the next few weeks

Nowadays people just buy some brand name mass produced item, your not one of the cool kids if you don't have an overpriced Invidia, DPE (Manta), Harrop, XForce

Support your local performance shops

 

[daves8]

The buy of the shelf stuff seems to be made to cost, more so made to perform and sound good, thin walled, small bodied, packed loose if your lucky, packed with nothing if your not

From my experience people always use to have custom exhausts made with the number and size of mufflers and resonators optional, I remember on many occasions getting an exhaust built, then tuning it over the next few weeks

Nowadays people just buy some brand name mass produced item, your not one of the cool kids if you don't have an overpriced Invidia, DPE (Manta), Harrop, XForce

Support your local performance shops

View attachment 244190

That was always my philosophy, but after a couple of attempts and not able to achieve no drone I gave up.

As a side note, is stainless or mild steel more likely to drone?

I know mild steel tends to achieve a deeper note

 

[someguy360]

As a side note, is stainless or mild steel more likely to drone?

I know mild steel tends to achieve a deeper note

I've never found any conclusive evidence that the type of material reduces certain frequencies. It does have a different note to it, but doesn't seem to impact overall resonance too much.

Wall thickness of the pipe would come into play more in my opinion than the type of pipe itself. Thicker is better.

 

[phantom0817]

Interesting thread.

I like the snap/crackle of the stock VFII but the note is not deep enough or loud enough for me. I know you can delete the middle resonator but I expect that just makes it louder, no deeper?

I like the deep sound of the dpe but from experience on VFII you loose basically all the snap/crackle.

I want something with a deep note but nasty with pops and crackles and a pulse, not a smooth purr.

Is it possible or am I dreaming? I’m thinking of starting with a manta catback due to H pipe seems to give some character lost with dpe judging from YouTube videos, but beyond that no ideas, except maybe a cam might shake things up?

 

[someguy360]

Is it possible or am I dreaming? I’m thinking of starting with a manta catback due to H pipe seems to give some character lost with dpe judging from YouTube videos, but beyond that no ideas, except maybe a cam might shake things up?

The manta systems do sound really good on the VF's that I've heard.

I'm still a big fan of H pipes over X pipes for sound, you do suffer a little bit in performance but it gives a much better note. A cam will give you a better note again.

But yes, the manta system will give you that depth you are after. Make sure you do headers with it too, the stock manifolds leave a lot to be desired.

 

[RevNev]

I like the snap/crackle of the stock VFII but the note is not deep enough or loud enough for me. I know you can delete the middle resonator but I expect that just makes it louder, no deeper?

VF2 is louder with the bimodal valves open than a traditional Holden V8 stock exhaust, but the note I think is dreadful, tinny raspy mechanical muffler sound. The deep smooth sound as we've mentioned in this thread is down to fibreglass packing perforated tube mufflers like a hot dog design. The stock mufflers are mechanical expansion chamber types destined to produce a tinny raspy (crap) note. You can't get a good note using the stock mufflers or the bimodal as their design doesn't produce a deep smooth sound.

The snap/crackle or back cackle on overrun is tuning induced but the smoother the note under acceleration, the smoother or softer the crackle on overrun. Other than a turbo with anti-lag, a properly tuned naturally aspirated engine shouldn't back cackle on overrun despite the popularity of it!

I’m thinking of starting with a manta catback due to H pipe seems to give some character lost with dpe

You can run it with no balance or H-pipe (full dual) for more "pulse" or the "old school" 350 Chev note and H and X-pipes on road car exhausts make no horsepower differences, it's all nonsense and just changes the note.

 

[daves8]

The X pipe in the DPE is in the 2 joined resonators, I understand it’s essentially just a hole between the two.

Could you add a H pipe before the resonators and gain the Traditional H pipe pulse?