Kung-Foo-Kamel
New Member
- Joined
- Aug 19, 2006
- Messages
- 182
- Reaction score
- 6
- Points
- 0
- Age
- 49
- Location
- Rockingham
- Members Ride
- Custom Hilux with a V6 Ecotec
After a week of messing around, cutting welding bending etc etc etc..
I have finally found a system that sounds good and produces solid torque with a increase in power through all rev ranges
Firstly, I was running a 3" Single sytem from the cat back, this lost me some torque at the bottom end but after 2500rpm it was like a power band kicked in all together it sound ok and gave good top end power
I also tried this system on a SV6, not recomended, it lost all its torque and gained nothing up top, these 190kw motors really like there back pressure
Then I thought hmm extractors, I got a set of HM Headers and put them on with no Cats, there 2.5" out into the single 3" system
All I can say is bloody noisey, horrible sound and it had a vibraty sound that kicked in at about 2500rpm, made me sick, but produced awsome power
I then thaught OK wheres this resonence coming from, so I put my stock single 2" back on and oh my god, all I could here was vibrating resonence every time you reved the engine, It was comming from the intermediate muffler
It sound like the left and right bank were arguing over who has right of way through the exhaust, so I thought OK lets try and slow the flow a little, and I installed 2x 2.5" Cats and I shortend the Extrators by about 3" and it made the world of difference, but there was still a little bit of resonence, so I tried a twin 2.5" system with intermediate and rear free flow mufflers and bingo, smooth clean pure note, very V8 ish, this setup has given me the best torque as well, I can be at 1000rpm in 6th gear and it will accelerate away, where before it was drop it back to 4th
Also we found the best cat back on a SV6 is the stock 2" twin system from a SS Gen3, just dont use the rear muffler and have straight pipes made up instead, this car prefers mufflers with restriction, if you use free flow type mufflers it appears to loose all its power
Anyway hopfully this info helps someone out, as I have just spent a small fortune on getting this Alloytec to sound good and produce good power, its not like the old buick V6, just remove the rear resonator and thats it
Cheers KFK
I have finally found a system that sounds good and produces solid torque with a increase in power through all rev ranges
Firstly, I was running a 3" Single sytem from the cat back, this lost me some torque at the bottom end but after 2500rpm it was like a power band kicked in all together it sound ok and gave good top end power
I also tried this system on a SV6, not recomended, it lost all its torque and gained nothing up top, these 190kw motors really like there back pressure
Then I thought hmm extractors, I got a set of HM Headers and put them on with no Cats, there 2.5" out into the single 3" system
All I can say is bloody noisey, horrible sound and it had a vibraty sound that kicked in at about 2500rpm, made me sick, but produced awsome power
I then thaught OK wheres this resonence coming from, so I put my stock single 2" back on and oh my god, all I could here was vibrating resonence every time you reved the engine, It was comming from the intermediate muffler
It sound like the left and right bank were arguing over who has right of way through the exhaust, so I thought OK lets try and slow the flow a little, and I installed 2x 2.5" Cats and I shortend the Extrators by about 3" and it made the world of difference, but there was still a little bit of resonence, so I tried a twin 2.5" system with intermediate and rear free flow mufflers and bingo, smooth clean pure note, very V8 ish, this setup has given me the best torque as well, I can be at 1000rpm in 6th gear and it will accelerate away, where before it was drop it back to 4th
Also we found the best cat back on a SV6 is the stock 2" twin system from a SS Gen3, just dont use the rear muffler and have straight pipes made up instead, this car prefers mufflers with restriction, if you use free flow type mufflers it appears to loose all its power
Anyway hopfully this info helps someone out, as I have just spent a small fortune on getting this Alloytec to sound good and produce good power, its not like the old buick V6, just remove the rear resonator and thats it
Cheers KFK