3" centre pipe & resonator for MY07 GT TB STI

[GTSPECB STI]

Here are some pics (camera phone) of recent fabrication and install of 3"s/s centre pipe and resonator completed by Nik at Allstar Garage. Awesome rumble, no highway drone and its unleashed heaps of usable power now. Also re-tuned by Sean at ASG. Now 180 kw atw and 414 Nm torque. Standard boost and AFR of 11.2. Awesome work and value for money if I do say so. Running Phat Down Pipe in 3" as well.

[libsti]

looks good,whats it sound like?

[Mano™]

NIce mate nice.. how's it sound? deeper I take it?

Looks like someone bought a gready fmic there in the box

[Arith]

Looks great, Dave! Shouldn't be any additional in-cabin noise with the STi mufflers. But note should definitely be deeper and more menacing with the dump pipe and larger exhaust piping. Great to see weld points along the curves rather than crumpled steel.

[dwayne]

Looks great Dave, very jealous !

Got a sound recording yet ? We need one for Jim's zorst thread.

Dwayne

[adam]

Great to see weld points along the curves rather than crumpled steel.

just a question about this comment. when something says "mandrel bent"
is that what this is trying to avoid?

[Arith]

when something says "mandrel bent"
is that what this is trying to avoid?

Si senior. A mandrel bent pipe maintains it's diameter throughout, even at the centre of the bend. Some of the less quality exhaust shops will bend the piping using a normal bender, but that decreases diameter as the pipe 'crumples' at the bend, thus creating more backpressure.

Mandrel bending equipment is expensive though, so the better shops will cut and weld existing mandrel bent pipes to get the angle required without reducing pipe diameter.

[adam]

although i'd imagine it would only be slight, is the outside of the curve in a mandrel bent pipe thinner or do they kinda squash up the inside of the curve? or is the difference not worth worrying about?

[GTSPECB STI]

Looks great Dave, very jealous !

Got a sound recording yet ? We need one for Jim's zorst thread.

Dwayne

Just made a recording of the new exhaust and will post up after lunch today.

[suff]

although i'd imagine it would only be slight, is the outside of the curve in a mandrel bent pipe thinner or do they kinda squash up the inside of the curve? or is the difference not worth worrying about?

Yes, it does result in a thinning in the pipe wall, standard pipe beinding also stresses the steel, resulting in stress fractures. Granted this will almost never be an issue on a stock exhaust, mandrel bent pipes are always the best option (as long as they are well welded!) many cowboys out there wielding a welding rod and calling themselves pro's! (especially with stainless)

[TheFirstEskimo]

Hmmmm. The guys at ASG fitted my dump pipe bout a year ago, thinking of returning to get the centre pipe done and retune (i just fitted new mufflers also). May I ask what they charged for the centre?