Originally Posted by chris4x4
For that matter, All newer vehicles have tuned intakes. If a simple spacer made that much difference, the manufacture would have lengthened their intakes another 1/2"
Yeah I know, just trying to throw LCE a bone of sorts, lol.
As far as plenum tuning, even a very small amount can make a difference (even with the loss of velocity), but it can also cause you to lose power in certain ranges, like you said the OEM spends a lot of money trying to extract as much power as possible within reason..there are quite a few factors at work when it comes to how the air will travel through plenums and ports...I have built several types of manifolds allbeit for forced induction vehicles so it does not really apply to NA motors the same exact way since under boost it is being force fed..
If the TB spacer worked as well as they say Toyota would have made the plenum 3/4 ish inches deeper like you said, I am sure they tuned it to be as good as it can get for whats on the table...
IMO TB spacer = less gas money, lol. And that Fking stupid whistling sound...gawd!