Weak links in Gen4 Exhaust. Is the Y pipe?

[Newbie GT]

Replace entire system inc Y pipe.
3inch then 2.5 is Y pipe .. Just do it once and do it properly.

[mynameisdaniel]

Mufflers will be a limiting factor. They're limiting me quite a bit (190kW). Going from 2.5" pipes to the crush bent skinny muffler pipes gives me huge minor losses in the flow. There's definitely gains in doing the mid section, I don't see why you wouldn't.

If you can get your hands on a Phat dump pipe his has a reducer that makes it a smooth transition from 3" to the stock centre.

[PoidaGT]

My advice is to get an X force mild steel dump, centre and Y pipe.
No point having shiny stuff under the car when you don't need to pay extra for it.
Rear mufflers only restrict top end power by a small margin until you chase big power applications.
Mild steel systems are very cheap and it allows you spend more on other mods.

[Newbie GT]

My advice is to get an X force mild steel dump, centre and Y pipe.
No point having shiny stuff under the car when you don't need to pay extra for it.
Rear mufflers only restrict top end power by a small margin until you chase big power applications.
Mild steel systems are very cheap and it allows you spend more on other mods.

Perfectly said !

[Kekotic]

My advice is to get an X force mild steel dump, centre and Y pipe.
No point having shiny stuff under the car when you don't need to pay extra for it.
Rear mufflers only restrict top end power by a small margin until you chase big power applications.
Mild steel systems are very cheap and it allows you spend more on other mods.

Mild steel is good if you don't plan on keeping the car for a long time, but I noticed mine is starting to rust a little in sections. So I'll either repaint it to make it last a few more years, or just go stainless. But I do think my exhaust note is perfect right now so I don't really want to change it.

[Newbie GT]

My advice is to get an X force mild steel dump, centre and Y pipe.
No point having shiny stuff under the car when you don't need to pay extra for it.
Rear mufflers only restrict top end power by a small margin until you chase big power applications.
Mild steel systems are very cheap and it allows you spend more on other mods.

Mild steel is good if you don't plan on keeping the car for a long time, but I noticed mine is starting to rust a little in sections. So I'll either repaint it to make it last a few more years, or just go stainless. But I do think my exhaust note is perfect right now so I don't really want to change it.

Don't spoil it by going stainless kiren and mild steel will last many many years long as it's cared for and painted / coated

[Kekotic]

Don't spoil it by going stainless kiren and mild steel will last many many years long as it's cared for and painted / coated

It was painted 2 years ago, but it's slowly peeling off around the welds. Will take it off and paint again

[Newbie GT]

Don't spoil it by going stainless kiren and mild steel will last many many years long as it's cared for and painted / coated

It was painted 2 years ago, but it's slowly peeling off around the welds. Will take it off and paint again

Nice like I said just care for it but seriously don't change as it sounds great.

Will always go mild steel

[Shaheenis]

The only one that must have read my post (viewtopic.php?f=55&t=20992#p355057) is mynameisdaniel with his suggestion of the PHAT dump pipe as the whole point is I don't want to replace the rear mufflers and don't want an aggressive step in any part of my exhaust. I think having this step from 2.25" to 1.5" even at the rear is going to negate any improvements gained from slightly increasing the diameter of the stock CAT back exhaust.

My goal is to remove the greatest restriction in the exhaust with the least amount of fuss and modification. Mild steel is fine but you don't seem to save that much ($200 in total if compared with a TB TCP delete muffs for $1199). This is what I wanted to do but I don't want 2.25" meeting 1.5" as per my previous post, this would be worse for flow than having a smooth transition and smaller rear section which is still 3" rear combined!

Just curious, if the PHAT dump pipe steps down to meet the size of factory exhaust, why would people use these unless they were only replacing the dump?

[imania]

The phat dump also comes with a three inch flange too, so you use whichever one fits your stock or aftermarket system. Best of both worlds

[Kekotic]

Just curious, if the PHAT dump pipe steps down to meet the size of factory exhaust, why would people use these unless they were only replacing the dump?

Because its an adaptor on the end. you just take that off if you are not keeping the stock centre.

[Newbie GT]

The only one that must have read my post (viewtopic.php?f=55&t=20992#p355057) is mynameisdaniel with his suggestion of the PHAT dump pipe as the whole point is I don't want to replace the rear mufflers and don't want an aggressive step in any part of my exhaust. I think having this step from 2.25" to 1.5" even at the rear is going to negate any improvements gained from slightly increasing the diameter of the stock CAT back exhaust.

My goal is to remove the greatest restriction in the exhaust with the least amount of fuss and modification. Mild steel is fine but you don't seem to save that much ($200 in total if compared with a TB TCP delete muffs for $1199). This is what I wanted to do but I don't want 2.25" meeting 1.5" as per my previous post, this would be worse for flow than having a smooth transition and smaller rear section which is still 3" rear combined!

Just curious, if the PHAT dump pipe steps down to meet the size of factory exhaust, why would people use these unless they were only replacing the dump?

There is no modifications. Get a dump and full system and be done with it.
Bolt straight up that is not modifying.

[mynameisdaniel]

My advice is to get an X force mild steel dump, centre and Y pipe.
No point having shiny stuff under the car when you don't need to pay extra for it.
Rear mufflers only restrict top end power by a small margin until you chase big power applications.
Mild steel systems are very cheap and it allows you spend more on other mods.

Mild steel is good if you don't plan on keeping the car for a long time, but I noticed mine is starting to rust a little in sections. So I'll either repaint it to make it last a few more years, or just go stainless. But I do think my exhaust note is perfect right now so I don't really want to change it.

Mine is also starting to get quite a bit of surface rust. Was only lightly painted by the exhaust shop using a rattle can though. Planning on taking it off, sand blasting or something and repainting it properly. It'll take ages for the rust to go through it but it does look a little unsightly and you can see the exhaust quite easily from the rear of the car.

As other said the Phat dump uses a sleeve adapter so you can get a 3" flange added or have a mid pipe made up that uses a sleeve connection to the 3" section.

[PoidaGT]

Not sure if Phat makes downpipes anymore.

He used to get the Liverpool exhaust shop to replicate the HKS downpipes.

Bugger all difference on the dyno between most downpipes.

If TCP do a stainless Turbo back system with rear muffler delete for $1200, I would do that for sure.

Only add the mufflers on a wagon if you like your exhaust extremely loud.

[blacktop™]

Not sure if Phat makes downpipes anymore.

He used to get the Liverpool exhaust shop to replicate the HKS downpipes.

Bugger all difference on the dyno between most downpipes.

If TCP do a stainless Turbo back system with rear muffler delete for $1200, I would do that for sure.

Only add the mufflers on a wagon if you like your exhaust extremely loud.

He does still sell them...I got one fitted by him a coupe of weeks ago.

And they are his own design for the 2.5's as no jap companies make a 2.5 dump pipe...he copied the design of the hks for the 2.0 GT.