Question Re: Turbo Back Exhaust...

[Macca86]

Hi everyone. I have a 2005 XR6T ute and I was looking to get just a cat-back exhaust put on but the exhaust place I went to has suggested I instead get a 4" dump pipe, new cat, and then cat back as well installed. I was under the impression if I was to fit a dump pipe and new cat it would require having a retune done. A quick search around on here and I have found a range of different comments (although I did find most mention needing a tune due to overboost?). The exhaust place is assuring me he fits this set up to BA's all the time and has had no problems. Is anyone on here running the same exhaust and hasnt had a tune done? Or can anyone please confirm 100% I will or wont need a tune? Ute is 100% stock atm and I wont be looking at really doing any other powergain mods so if Im going to need a tune Id rather just stick with a cat-back as I dont want to be spending money on a tune as well.

[freeze_dk]

Retune 100% if turbo back, not to sure on cat back. Don't think it will affect it but don't quote me

[discostig]

Have read often that cat back is fine, no tune needed.

Changing dump and/or cat is retune time as it overboosts.

[Macca86]

Cool thanks for confirming that for me guys! Might just stick with the cat back for now then until I save up and can get a dump/cat/tune done all at the same time

[jas98]

cat back system can and will most ikly cause overboost, maybe not straight away but on a cold night it will. herd about it a fair few times

[Pazzo]

Don't think a cat back on a stock car will cause over boost as the restriction is the cat on a stock car..

[Henz]

Just chop the centre muffler or get a bolt in muffler replacement. Wella.

[Cameron02]

Don't think a cat back on a stock car will cause over boost as the restriction is the cat on a stock car..

Yes, I believe this is correct.

Since the cat is the main restriction, anything you do past or ahead of it (in regards to air flow) should make almost no difference to performance. Once the cat is replaced then any other air flow mods should start to have an effect on performance.

Just chop the centre muffler or get a bolt in muffler replacement. Wella.

My ba had a removed centre muffler when I bought it. It was 90dba and 93bda on deceleration. I replaced the muffler back to stock and it was 81dba. So it definitely makes a difference to sound and might be the best value option until you can afford to do the rest. If you buy a "centre pipe" from someone make sure its for the Ute as its different to the sedan.

[jas98]

ask tuners, cat back system can cause overboost........even if cat is stock!

[jas98]

also reson why when cutting standard center muffler out and welding striaght pipes on nd not getting overboost, is because the center muffler is a straight through muffler anyway...the rear one is the restricted one, (in stock form)