Exhaust for AFM SS Commodore

[Foggsy]

I hate AFM, there's my 2 cents worth. I have a 2012 manual with the L77 engine so to do any decent sort of cam I have to crack the heads. If i had a time machine i would go back and shoot the person that signed off on fitting AFM in any commodore. Its simply SH%T!

 

[PIR4TE]

I hate AFM, there's my 2 cents worth. I have a 2012 manual with the L77 engine so to do any decent sort of cam I have to crack the heads. If i had a time machine i would go back and shoot the person that signed off on fitting AFM in any commodore. Its simply SH%T!

Not a PITA if you do 1000k's a week. mostly flat plains.
Get the AFM mode tuned how you want when you have mods done.
Understand that the exhaust needs to be about 18" longer than appears on the vehicle, as per loop in stock muffler. That correlates to our engine's resonant frequency of 118hz at 1800 rpm +/- 300 (1500-2100rpm), so any aftermarket pipe needs to address this, and the halved Doppler of AFM when engaged (60hz).
Otherwise you can get any size and type of pipe you like and fix the drone with a helmholtz setup for about $300.

 

[PIR4TE]

TIP: AFM tune and helmholtz - gets me daily reliable 270+rwkw, all torque, 9.5l/100k on ethanol = $10.45 per 100k, with 350kg of gear.
AFM saves me $50 a week and performs and sounds like it should without being a nuisance:
http://www.youtube.com/watch?v=XIDyCv_t7WI
http://youtu.be/OuDtjAuZJfM

 

[WazzaV8]

TIP: AFM tune and helmholtz - gets me daily reliable 270+rwkw, all torque, 9.5l/100k on ethanol = $10.45 per 100k, with 350kg of gear.
AFM saves me $50 a week and performs and sounds like it should without being a nuisance:
Xforce 2.5" VE on dyno - YouTube
SSV AFM 2.5" tuned - YouTube

A bit unbelievable that you get 9.5L/100km on E85, I only get that on premium 98 and a car car isn't as economical on E85 having to use about 25% to 30% more than with premium fuels.
Where did you get the Hemholtz resonator from, I can't find them anywhere on the Internet?
All I can hear on your video is your cars stereo blaring some jungle bunny music, I prefer listening to drone.

The best way to stop drone is by changing mufflers, as a muffler muffles sound, the more restrictive the less noise, the less restrictive the more noise pretty much common sense stuff. On a Xforce system if you want to get rid of drone get the Varex mufflers, when country cruising shut the butterfly valve and you can't hear them but when in the city and leaving for work at 4am open the butterfly valves that way your not the only person awake at that hour.

 

[WazzaV8]

Stuff the AFM, who needs it. Is there much involved with shutting the AFM off

No, a tune shop can turn it off for you for maybe 300 bucks, but really is it worth it as AFM doesn't interfere with the car in anyway when you want the power only when your putting along.

 

[PIR4TE]

A bit unbelievable that you get 9.5L/100km on E85, I only get that on premium 98 and a car car isn't as economical on E85 having to use about 25% to 30% more than with premium fuels.

Prolly during PE over 2k rpm but trims around 18-25% (driving miserly), its fair dinkum using fillup over actual klm travelled Gold Coast to Gladstone, Canberra to Balranald.

Where did you get the Hemholtz resonator from, I can't find them anywhere on the Internet?

Lookup US counterparts on the export G8 forums - I could PM you some design specs that I worked out, take them to an old school exhaust shop, easy.

All I can hear on your video is your cars stereo blaring some jungle bunny music, I prefer listening to drone.

BBBBBB Bonfire! Haha OK just for you white fulla, a hifi unedited squeaky seat and muttering swear words at ricers exhaust experience:
http://www.youtube.com/watch?v=Acly2zPi3d4

The best way to stop drone is by changing mufflers, as a muffler muffles sound, the more restrictive the less noise, the less restrictive the more noise pretty much common sense stuff.

That's the most common way, fit the original muffler with the extra 18" coiled inside sure, but not the way to keep unrestricted (and even enhance performance). Nissan GTRs for example need huge twin turbo flow and a few aftermarket offerings use pulse frequency canceling same. Remember the Cortina 1600 came out with them and a few other F. f. frds

On a Xforce system if you want to get rid of drone get the Varex mufflers, when country cruising shut the butterfly valve and you can't hear them but when in the city and leaving for work at 4am open the butterfly valves that way your not the only person awake at that hour.

Yes I hear you, but even Varex shut it still drones and is hella restrictive.

 

[MYVESSV8]

A bit unbelievable that you get 9.5L/100km on E85, I only get that on premium 98 and a car car isn't as economical on E85 having to use about 25% to 30% more than with premium fuels.
Where did you get the Hemholtz resonator from, I can't find them anywhere on the Internet?
All I can hear on your video is your cars stereo blaring some jungle bunny music, I prefer listening to drone.

The best way to stop drone is by changing mufflers, as a muffler muffles sound, the more restrictive the less noise, the less restrictive the more noise pretty much common sense stuff. On a Xforce system if you want to get rid of drone get the Varex mufflers, when country cruising shut the butterfly valve and you can't hear them but when in the city and leaving for work at 4am open the butterfly valves that way your not the only person awake at that hour.

they're are generally called J pipes, can be found on ebay, if you search VE commodore exhausts you'll find them, basically a straight through pipe with a big J welded to it, have a look here WazzaV8, I like them, and have a set (all noise no kw gain) Commodore VE Performance Exhausts Sedan Sportwagon | eBay

 

[PIR4TE]

No mate, they're straight through axle backs with a pipe welded in a j shape!
Bolt-on cop callers.
They'd be bloody loud, nobody I've read has anything nice to say about 'DG' racing tips after any long mileage.
Yes similar form but sort of the opposite function.
My cabin noise with cancellation never gets above 45db (until about 4000rpm) with proper muffler and J-Pipes (helmholtz chamber).
You are right though, J-Pipes and muffler don't *make* power, they let you keep your de-restricted power without making a noisy droning nuisance.

 

[PIR4TE]

FWIW here's a link to one of the GTR racing development articles which claims more power using helmholtz chambers, though my point was same power less annoyance http://www.gtrlife.com/forums/topic...helmholtz-resonance-to-increase-engine-power/

 

[MYVESSV8]

PIR4TE, my explanation was vague true, just trying to give the OP an idea what to look for so he can visualise what a helmholtz chamber is, with your ref to G8 forum he would/should have a better understanding of what the are, I know from reading alot, the guys in the states do generally call them J pipes even if thats not really true, was some interesting reading too. I cant remember what make mine were but got them for nothing (well $5 petrol to pick them up) young fella had bought them for his V6 and as they sounded like crap (not suitable as freq all wrong) he was offering them free, so thought why not,I havent had any issues with the boys in blue at all, had mine for about 2 yrs, quite a nice crackle on over-run, nice and quiet while cruising (bathurst trip 2500klm) and no probs give it some stick and it wakes up though and have a less restrictive exhaust to go with headers, hiflows etc