Running stock rear mufflers on aftermarket exhaust and tune

[PSISLE]

Hi all, quick question. I’ve got an L77 sportwagon with Cam, full harrop 2.5inch system with 1 3/4 headers- has been dyno tuned. Sounds killer and goes like stink. Making the trek to bathurst this year from SA and I wanted to get the opinion of the educated majority that lurks in here. Would it be safe for the car/tune to install either the stock afm mufflers or even vf2 mufflers (would have to have flange mounts) just for the trip to save the ears of my passengers? I’m used to it, but fully loaded with gear, 3 blokes and small trailer- I wouldn’t want to sit in the back for 12 hours
Thanks team JC

 

[vr304]

Tell your passengers to suck it up either that or turn the stereo up

 

[vr304]

Tell your passengers to suck it up either that or turn the stereo up

 

[Pablito]

Guys i know with cammed cars have Varex bi modal mufflers on their cars. When put in quiet mode it's basically as quiet and restrictive as stock mufflers and their cars seem to be fine.
I wouldn't give it a flogging with stock mufflers on it though.

 

[monstar]

Totally safe, likely more efficient under 3k RPM.
I have same spec as above (same body too) did a test on a dyno several pulls with bimodal mufflers, open and shut.
Result was no measurable performance difference under 3300 RPM, which is pretty much >90% of the drive time.
For me that confirmed a few things, mainly that with a tuned system there is no point pfaffing around with a loud exhaust on the highway.
The only time it would restrict performance (by about 15 HP) is flat to floor WOT getting up to speed on-ramp or snicking way back three clicks to 3rd gear for a serious F1 style fly-by overtaking demonstration.

 

[PSISLE]

Totally safe, likely more efficient under 3k RPM.
I have same spec as above (same body too) did a test on a dyno several pulls with bimodal mufflers, open and shut.
Result was no measurable performance difference under 3300 RPM, which is pretty much >90% of the drive time.
For me that confirmed a few things, mainly that with a tuned system there is no point pfaffing around with a loud exhaust on the highway.
The only time it would restrict performance (by about 15 HP) is flat to floor WOT getting up to speed on-ramp or snicking way back three clicks to 3rd gear for a serious F1 style fly-by overtaking demonstration.

Thanks monstar, would you suggest to go with the stock afm cans or get vf2 bi modals? Next question, which models came with flanged mufflers?

 

[3rspecB]

Next question, which models came with flanged mufflers?

All VF2 V8 models that don't have rear brembo's have flanged mufflers. Only Redline and LE models have the flared muffler flanges.

 

[3rspecB]

Double post

 

[lmoengnr]

All VF2 V8 models that don't have rear brembo's have flanged mufflers. Only Redline and LE models have the flared muffler flanges.

The Magnum has flanged mufflers.
VF seems have a few different configurations.

 

[3rspecB]

The Magnum has flanged mufflers.
VF seems have a few different configurations.

I haven't been under a magnum so my bad but have been under all other VF models. Planet parts has heaps, contact them and ask for sedan/wagon flanged VF2 bi modal mufflers.

I'm visiting my ex colleagues at Holden HQ next week so will ask the ? about the magnum. I remember something about the rear brembos and Redline thicker rear swaybars and swaybar rod..

 

[lmoengnr]

I haven't been under a magnum so my bad but have been under all other VF models. Planet parts has heaps, contact them and ask for sedan/wagon flanged VF2 bi modal mufflers.

I'm visiting my ex colleagues at Holden HQ next week so will ask the ? about the magnum. I remember something about the rear brembos and Redline thicker rear swaybars and swaybar rod..

I was surprised when I looked under the bum and saw the flanged mufflers.
Nearly every pic I've seen in regards to VF exhausts have the ball/socket connector.
Made me smile though, have an E3 Maloo 2.5" center section that should bolt straight up, just need a couple of bungs for the O2 sensor holes.