Exhaust on v6 sti without a tune Is 3" better than stock
 

Ok,

Im looking into getting a 3" turbo back exhaust for my car, but am looking for other peoples experience with the same car V5/6 sti. Do they loose their power up in the revs compared to the standard exhaust without getting a tune?

Will the car have the same power band that it has or would i be better off just getting a diff back exhaust.

What are the chances of doing any damage to the engine?

I really dont want to get the car tuned, and am not really looking to change the current power, but want a little exhaust note.

Thanks

Tom

Hi Tom,

Interesting question. My ver 6 has stock zorst, Ross's has a 3" system. On
saturday night I took Ross for a cruise in my car and he did remark that
even though it had the stock system it still had plenty of pull. To the point
he was thinking about going back to stock to make it a bit quieter.
Feel free to add your 2 cents worth Ross.

I am getting a 3" system on mine in the next week or so and will be able
to give you a better idea once that is done.

In general, I don't believe it needs a retune at all (assuming you have the stock ECU).
But it should spool up and reach peak power a bit quicker. No more power, just
peak sooner.

Someone else will probably jump in here shortly.

Cheers,
Ian.

The old classic GC8s tend to be ok without a tune with TBE and filter upgrades.
However, when you start changing the turbos and intercoolers, then it could change the overall limits of the stock ECU and will require some form of tuning to get not only max benefit of the mods but for driveability and reliability

If you just want the boxer note just go diff back then your not losing nor gaining power. ;)

[QUOTE=SPEC IV]If you just want the boxer note just go diff back then your not losing nor gaining power. ;)[/QUOTE]

Or fuel economy :)

I have an Xforce 3" turbo back on my V6 STI.
Mine has the venturi/ wastegate splitter in the dump pipe and the (wanky) angled (think N1) rear cannon.

Boost builds about 200-300 rpm earlier than the stock system. The real performance gain is crisper on it - off it - on it again responsivness, felt most when your on boost, then lift off mid corner and stand on it exiting the corner, the power feels very punchy.

High rpm power doesn't drop off as abruptly as the stock system either.

Logging the boost pressure shows it peaking briefly at 18.5 psi (@ midrange rpm) then tapering to 16.5 by redline, I believe the stock system stiffles the hi rpm boost more, to around 15 psi @ redline.

Fob's STI felt smoother than my car on boost (+ the ECU now knows what it's doing after an AFM change), but I'm on modded suspension, stiffer sway bars, 17's shod with low profile RS 2's and have all urethane bushes so my car inherently feels rougher.

My 3" doesn't drone or resonate through the car, but I'm still thinking of changing the rear can for something a little more neighbor friendly.

So from my point of view: Get a decent dump pipe for crisper throttle response and less boost taper, 3" mid pipe with a resonator (to keep drone at bay), 3" under diff to an effective but free flowing end can (avoid cannons!).

I've run 3" systems on all 4 of my subies thus far, the change it makes will suprise you in a good way. :D

Your welcome to have a drive anytime you like, just Pm me to arrange it.

HTH

[QUOTE=WhiteRX]Ok,

Im looking into getting a 3" turbo back exhaust for my car, but am looking for other peoples experience with the same car V5/6 sti. Do they loose their power up in the revs compared to the standard exhaust without getting a tune?

Will the car have the same power band that it has or would i be better off just getting a diff back exhaust.

What are the chances of doing any damage to the engine?

I really dont want to get the car tuned, and am not really looking to change the current power, but want a little exhaust note.

Thanks

Tom[/QUOTE]

You will get a modest power increase and you won't need to re-tune. You will not damage the engine.....and you will have a nice exhaust note. Don't bother with diff back.

[QUOTE=fobz]Hi Tom,

Interesting question. My ver 6 has stock zorst, Ross's has a 3" system. On
saturday night I took Ross for a cruise in my car and he did remark that
even though it had the stock system it still had plenty of pull. To the point
he was thinking about going back to stock to make it a bit quieter.
Feel free to add your 2 cents worth Ross.

I am getting a 3" system on mine in the next week or so and will be able
to give you a better idea once that is done.
[/QUOTE]

Why don't u and Ross swap? If u want 3" and he wants stock... Just an idea.. :P

I don't want stock! I'm just thinking of toning it down a little.

I'll probably just swap the cannon over to something with a little more internal volume.

So i guess that the general consensus is that the 3" turbo back wont hurt my car and may help give her a little more power then. Will have a think about it.

Thanks

Tom