Yea i guess that's the next step. Has anyone alse had this issue with just adding an intake on their car? why do I feel like I am the only one?

 

The good thing is you'll be able to squeeze every last pony out of the intake with the S-AFC tuned!

 

SAFC, you don't really need to get it professionally tuned unless you want to. All you have to do is correct for the cross sectional difference in area. The stock piping is 2.6" and going to a 3" pipe is a 15% increase in size. Thus it will usually slow the air velocity down to where it throws off the stock sensor. In the AFC, increase the MAF correction across the board by around 13-17% or so and you should be good. Best to still have a wideband to double check though.

 

ok cool, that doesn't sound as hard as i thought. Thanks a lot for the tip. Is there any particular AFC that you recommend? I noticed Apex has a few different models. I would think that I don't need the top of the line one for what I am trying to do.

 

If you pick up an Apexi unit, at least you'll have some support on the forums as alot of guys here have installed/tuned it themselves. I think they have an SAFC, SAFC II, and the newest, the Neo. Prices will probably vary according to whichever model is newer. You can get away with one of the older ones since you're only using it for basic air/fuel mix correction.

 

Any SAFC will work. Cheap used one will work fine. You're increasing the fuel all the way across the board to the same number. This is basically just tricking the stock ecu so it thinks the piping size is still stock even though you increased it by 15%.

 

I gotcha, when I pick one up and get it wired up....I may come back to you if I have more questions. Sounds pretty simple however. I guess the only question would be how do I know when I have increased the fuel enough. I don't want to be dumping gas in the motor and have my gas mileage start to suck

 

You're a Lexus tech right, shouldn't you guys know this already? jk

If you guys have a dyno and lambda meter(wideband) at your facilities then see if you can throw your car on the dyno. My friend works at a BMW dealership here and they have a $80k Dyno Dynamics machine...the machine I want lol. Anyways, if you don't have access to those then just hook up a wideband in your car to verify all the air fuel ratio is correct. Worse case, you can take it to a shop to get it tuned if you're not 100% confident in doing it yourself.

 

No with it tuned i.e. set to the right settings as far as air/fuel ratio it should actually make it better! When its not reading the correct air/fuel ratio then one or the other would be over compensating which would = Worse mpg!! Typically performance mods are helping the engine breathe, Give less restrictions which in turn gives more power and better mpg, But its a catch 22 because most people lay into the car alot more with the newfound power! So they wind up burning more fuel. It all lies in the driver and how heavy their foot is!!

 

Unfortunately we do not have a dyno, that would be nice however. I'm sure I would be able to figure it out. If i get the basic AFC, there is only so much adjustment that can be made.