how big is stock Turboback?
I'm going to get turbo back next week and I want to know how much hp I gain from it. Getting Helix turbo back kit.

Also will changing BOV make turbo sound louder? or do i have to do something else. I can barely hear my turbo.

 

idk about thr tme, but as for hearing the turbo i think what makes it louder is getting a cone style intake. i think the stock one muffles the sound

 

I believe stock is 2.5"

If the ONLY thing you're doing is a Helix Turboback (with test pipe) then you can expect up to a 20whp gain.

You'll find that most people don't recommend changing the BOV, unless you have a plastic stock VIII BOV, in which case the recommended change is a metal stock IX BOV. This is because the MAF sensor will meter the air, which you will then vent to atmosphere on a VTA BOV, causing performance loss, or worse.

You can try removing the plastic cover of the stock airbox (leave the channel there). This will make the boost a lot more audible. This, however, is up for argument because many say not to touch the stock airbox without a tune. So it's really your call.

 

And we're moving.....

 

I'm not sure on the diameter of the stock exhaust but I have the 3" helix turbo back and it feels quite a bit quicker. Also the exhaust is a really good fit and quality.

 

didnt you make a similiar post yesterday? I believe you got a bunch of answers that you were looking for. They are not going to change much.

 

yea i forgot to say if ur gonna touch the intake or switch to vta then ur gonna need a tune with it. depending on the year and model u might not need a new bov, and wont need one anyway if ur not turning up the boost

 

i did but I can not find my post. I thought it got deleted. I'll use advance search to find it. thank you

 

go to community then quick links, then click "subscribed threads" you should find it in there...

 

I just did search and my last post got deleted.

will evo 8 turbo back fit on evo 9?
I have 2006 evo 9 GSR

Thank you

 

probably the reason why...

 

I posted newbie question on general evo forum.
still waiting for evo 8 turbo back fitment on evo 9
while searching...

 

The Evo 8 exhausts will fit the Evo 9... but be sure the downpipe is designed to fit the ACD (like Helix v2 Downpipe).

One difference between 8 and 9 exhaust is, on the 8, the O2 sensor is on the catback midpipe, and on the 9, the O2 sensor is on the cat itself. This doesn't pose a problem if you're replacing the entire exhaust.

 

I'll be replacing turbo back so is that mean I dont have to worry about O2 sensor?

 

yea dont worry about it