You will theoretically increase the pressure differential between the Inducing and exducing side of the compressor.
That inturn will allow a less restrictive charge which should allow the compressed air to get to the valve quicker.
On the stock map you will be fine and will not lean out nearly enough to notice too much of an increase in power.
On the new EVO9 the mitsu engineers incorporate a Lean Spool map that under initial boost load the car will actually leanout when chaning intakes and running the stock ecu with the stock MAF.
These problems have actually caused exhaust ports to blow out and manifolds to crack in Japan.
The problem has since been resolved and the new 9's are ready for the upgrades.
But for our 8's it will have no ill effect.

 

Sweet, I didn't expect to save that much more... the only thing is I don't know how to install the dv or the intake. I'm afraid i'll screw it up so bad that I'll end up breaking my car lol. I guess i'll see how much they charge for installtion. If the labor is cheap then I'll have them install it otherwise i'll just look it up in the forums. haha what alarms do you guys use? I was thinking of getting the Clifford alarm system i don't want my new parts all stolen in one night

What's a turbo back exhaust? I'm serious haha i've never heard of that before.

 

The BOV is so easy to change. All it is is two hose clamps on either side. If you get the MR DV or the APS they bolt right in the stock location, you cant screw up. All you need for that is a screwdriver or better yet, a 10mm socket. Dont be scared.

The intake is a little more complicated but that only involves removing the stock air box. If that worries you just get the drop in filter, performance wise its probably a little better in the stock car anyways.

Do a search on the APS BOV. I wrote a little something a while back when I put it on. Theres tons of info out there on this stuff.

A turbo back exhaust (TBE) is just like it sounds. It is an exhaust system that replaces the stock exhaust from the outlet of the turbo all the way back. In the case of our cars, it starts at the 02 housing. A cat back is exhaust is one that replaces the stock system starting at the oulet of the catalytic convertor. The main difference is you will need a cat back to start with, then a downpipe (DP) to complete the remaining pieces. Some people consider a full TBE to include a test pipe (TP) to remove the cat. Personally I dont because then you arent emissions legal and a TP is theoretically for off-road use only.....not that I am eco friendly, just hate emissions problems during registering.

 

Thanks a lot for the info everyone. I'm going to do some more research on the BoV and the TBE. In the mean time i'm going to find a place that sells K&N Cone filter cheap and install that for now. Then make all my mods at once, (Intake, flash, BoV, dv) Is the diverter valve right after the BoV? Or are the two essentially the same thing? As for the TBE maybe i'll do that at the end of the year wtih my bonus... haha