I installed mine a couple of days ago and so far am loving it. Not too raspy and nice exhaust note. As to how much HP the Injen adds? I will dyno my Z sometime tomorrow and post results.
I dyno my car everytime I add a new performance part so I can get a good baseline figure of how much gain I get from it.
Right now I'm sitting at 302 RWHP and 306 TQ. I'm hoping to get 5-10 extra if I'm lucky.

-Bootay

 

I just found out that no more injen exhaust will be made till the release of the H Pipe from injen. (End of this month of the earliest)

 

what are ur other mods?

 

Injen intake, UR pulley, and 75 shot of N2O.

 

Oh was actually hopeing to see an all N/A list makeing 300rwhp.

 

Sadly no...you'll need to dig pretty deep in the pocket book to hit that mark. Although not impossible with the addition of cams, headers, flywheel, plenum, and rehash.

-Bootay

 

Ya. iam at 262 rwhp now with just intake, exhaust and test pipes. Iam curious to see what i will be at after pulleys and plenum (will be on nextweek). Hope the plenum doesnt actually HURT the HP.

 

If you're lucky you should get around 17-20 RWHP. Run a wideband dyno to make sure your A/F raito is where it's suppose to be since you're adding a plenum. Keep us posted with your results.

GL
-Bootay

 

Why would you want to have an "H" pipe on your true dual exhaust? Isnt it most optimal if each cylinder side can breath independently and free?

Also i think it would "mess up" the sound as otherwise there is 2 x 3 cylinder song comming out the rear where as otherwise it will be already mixed to 6 before exiting the car, this is ofcourse a lot up to your engine sound preferences though.

/Roger

 

17 to 20 RWHP from the Injen straight tip exhaust? That I gotta see. I will be interested to see your dyno sheets before and after as well. Please make sure you post your torque graphs.

An H or X pipe will usually mellow the tone of a dual exhaust and can help reduce boomyness. If you are running cat-less there is also may be some power gains.

With the smaller diameter piping and rear silencers of the Injen, it seems like an H would help improve flow.

But hey, it looks cool and sounds great.

Chris

 

[QUOTE=HyperSprite]17 to 20 RWHP from the Injen straight tip exhaust? That I gotta see. I will be interested to see your dyno sheets before and after as well. Please make sure you post your torque graphs.

I stated that Cloudy could see 17 to 20 HP gains with the pulley and plenum.

I'm hoping to get 5-10 HP gains with my Injen SES exhaust.

-Bootay

 

Oops, OK, yeah, it might get 5hp.

Chris