Originally Posted by RoadconeTuning

so how bad does it eff stuff up to use the stock airbox with the AEM elbow monstrosity? isnt that the real restriction?

Originally Posted by Wangspeed

"But someone said ___ intake does not throw off fuel trims"
It does throw them off. It needs to be tuned. This is not some ancient car. The car constantly tries to operate in closed loop, and as such is completely dependent on all of it's sensors to be in accurate working order. Throwing them off by doing things like changing the intake can damage the engine.

"But it doesn't set off the CEL"
Just because it doesn't set of the CEL, doesn't mean it's ok. If you saw the amount of knock and how skewed your fuel trims are, you would be singing a different tune. Literally.

"What if it's just 3-4% off"
3-4% off where? MAF tuning is much more complicated than simply saying it's a few percent off. Let's say it's rich in one spot, the ECU will attempt to remove fuel in surrounding cells. What if it was already lean in those other cells? This car already runs very lean, so if it's off just a little bit, that is not good.

"Someone said they've been doing fine without tuning"
Did they data log? No? Stop right there.

"Can I run GMS1 with an intake?"
No, not if you care about your engine.

"Do I need to get re-tuned if I already have a custom tune?"
Yes, I'm sure your tuner will discount a simple MAF tune.

"What if my tuner doesn't have MAF tuning available?"
Walk away! Just walk away!

"My tuner only tuned the intake on the dyno. Is that okay?"
No, probably not. You need to do a lot of steady state cruising at various RPMs and loads to produce a good MAF calibration.

I'll go on record as saying that changing the intake is the riskiest bolt on that you can do. You should not swap the intake on any modern car without tuning. If you are unwilling to do this, then go play with the exhaust side, or suspension. Just leave the intake alone.