VF1 SSV Redline Exhaust Modification

[RevNev]

The best "old school" muffler is the L2121, has an open chamber in the middle with the inlet and outlet perforated going through glass packed chambers.

Here's a bimodal modified Lukey style, sounds great with an R8/LSA midpipe with only 2 hot dogs. The stock canister's a good size to produce a great note and loud enough without drone.

 

[Forg]

I was not aware that Dr Frankenstein also did exhaust components!

 

[RevNev]

I was not aware that Dr Frankenstein also did exhaust components!

Yes absolutely, he designed the bimodal with it's consequent crap note and needed chopping up and re-working.

 

[Forg]

Yes absolutely, he designed the bimodal with it's consequent crap note and needed chopping up and re-working.

Interesting hypothesis on OEM this leads to ... "welded up out of used baked-bean cans" = "farty noise"!

Early on Saturday mornings, all around Adelaide, you used to see the Holden engineers scrounging through the metal recycling receptacles looking for materials ...

 

[Not_An_Abba_Fan]

Here's a bimodal modified Lukey style, sounds great with an R8/LSA midpipe with only 2 hot dogs. The stock canister's a good size to produce a great note and loud enough without drone.
View attachment 222192View attachment 222193

Or just buy a Manta muffler as that is almost how theirs are. Pretty sure they extend the twin pipes into the chamber a bit.

 

[mpower]

OP, I was in the same boat as you when I got my VF1 SSV Redline, love the car - not sure it's on because quiet.

I did full Magnaflow 2.5", Genie headers (short), VCM OTR, J-Pipes to eliminate drone and a powertorque dyno tune. very happy with the results.

So realistically the same as what you are looking at except I got the j-pipes. Not everyone wants/needs them but i think they improve things.

 

[RevNev]

Interesting hypothesis on OEM this leads to .

What it leads to, is re-designing a muffler optimally that Holden should've done in the first place.

 

[Not_An_Abba_Fan]

What is "optimum" really? In terms of power and economy, the exhaust system is basically useless, it is ONLY there to keep the car quiet. It serves no other purpose. (Apart from exiting the gases away from the passenger compartment). You think OEM will spend the R&D $$$ on a performance exhaust system? They would rather develop sensors to keep you off your phone.

 

[Skylarking]

What it leads to, is re-designing a muffler optimally that Holden should've done in the first place.

Yes, there is a lot of things GM/Holden should have done

From any manufacturers perspective, an optimal design would be the lowest manufacturing cost for the mass produced item... It could come down to saving 10 cent on a bit of steel or one less crimp which may make the exhaust sound much less emovitve from an enthusiests perspective...

Luckily, the SSVR actually got some design dollars to spend on the Bailey tip, the bimodal mufflers and the sound enhanser intake plumbing. I'd have loved if they were also allowed to spend some dolars on proper longer tube headers.

But in general, manufacturing enthusiasm left the car companies accounting department over a 1/2 a century ago

 

[RevNev]

What is "optimum" really?

We'll start at the exhaust manifold outlet of 2 1/8" a reasonable size outlet for a stock carburettor 308. The manifold outlet on a Chrysler 6.4 litre (similar size) SRT engine is 2 3/4". Holden fits a 2 1/4" V6 midpipe and muffler assembly to the LS3 buts drops to 2" over the trans tunnel brace and discolours from mass heat build up. Then the inside diameter of flexible bellow at the rear muffler flange reduces down to 1 7/8". Who ever signed off on that for a 6.2 litre 300+ kw V8 exhaust needs the sack! Alternatively, they could have fitted the R8/LSA 2.5" midpipe with the X-pipe and 2 hot dogs and saved on the V6 muffler assembly. Chrysler ran a twin 2.75" exhaust on their SRT engines far more optimally sized for a 6.4 litre Hemi.

We get to the bimodals and that's a joke seriously, here's the inside.

The Bimodal inlet is 2.25" with a 3" section of perforated tube fibreglass packed in the front chamber. From there to the outlet it's straight pipe, so a third of the muffler is used for sound control and that's why the bimodals have a lousy note with the valve open. With the valve closed, the exhaust gas has to pass through the perforated tube and the fibreglass packing to reach a few holes in the front chamber plate. With the valve closed, you may as well shove a bit of rag up the exhaust pipe and block it up creating mass back pressure. Again, I'd sack the designer of that abortion too!

What they should've done, is have the perforated tube end at the front chamber plate, leave an open centre chamber and the rear chamber instead of straight pipe, should've been perforated tube and fibreglass packed and that's a Lukey design and sounds magic and flows well enough with the valve closed. Holden could have done exactly that an no extra cost if sensibility prevailed. Instead, they mess around with that silly bit of tube off the airbox to the firewall for a fake intake roar and cut holes in the exhaust tip to leak noise under the rear bumper. That's supposed to impress enthusiasts the V8 Commodore targets, they're off their chops!