I decided to apply a scientific method to get an idea if the deckplate mod can have any real effect. As a guy with some HVAC background, I know a little bit about how air flows, and this test was fairly easy anyway. To test out if the deckplate mod has any effect all that one has to do is measure the vacuum in the chamber before the engine air filter.

The results: 0 vacuum under high load up a hill up to 4,000RPM. So for most real load situations there is no benefit whatsoever to putting holes in the airbox. None.

 

interesting findings....

 

Downer!!! Gosh! lol


Good info though.

 

it sounds cooler though

 

Good findings, now go do the ISR mod and see what you get...

Fink

 

ISR is the resonator box? Don't see how it could affect anything either, as replacing it with a straight tube does not increase volume and does not decrease turbulence. Is there a scientific explanation why it should work?

 

In theory, theory and practice are the same.

In practice, theory and practice are different.

In theory, nothing works but we know why.

In practice, it works but we don't know why.

When theory and practice come together nothing works and we don know why.

 

thats good, the less vacuum the less restriction, if you don't believe me then screw the deck plate in and then put a rag over the opening in the fender.

the only true way to tell if it does anything would be a dyno, and even then it would be hard to tell because there might be a 1-2 hp difference

 

Here's some more info: http://www.gadgetonline.com/AirInduction.htm

BTW, how about the "air elbow" mod? http://www.4runners.org/writeups/airbox/index.html

 

finally a real thread.

it makes noise. some may call that power. it is noise not power.

 

Ok so It really does do some thing!
No it is not going to give more horse power!
No it is not going to make it sound really cool!
And No it is not going to give you colder air, actually a little warmer!

I run it because it gives me better throttle response!
Less Restriction to the air box less restriction to the Cylinder!

if you really want more horse power it is time to spend some dough!

or install a diesel

 

Well I left my lab coat at the lab... but the best explanation I can give you is that by removing the ISR you are saving several pounds of weight [not that it would make a truly measurable difference but there it is] and you are creating a more direct air route with a smoother airflow characteristic... it does not increase volume but it does make it easier to move what volume there is thereby increasing the overall efficiency of the intake side which provides the performance "boost" albeit at the expense of a louder intake sound. The same reasoning lies behind the deckplate mod you don't increase the vacuum or volume but the engine does not have to work as hard to move the air meaning it can put more power to the ground in this case at the expense of a slightly increased chance of large particulate ingestion [which would be caught by the air filter so no risk to the engine just more junk in the airbox] and of course a noisier intake. edit: If you check the gadget link above you will see that the deckplate mod actually does yield a measurable increase in performance.

 

Maybe it varies from year to year, but when I look at my resonator box it is straight tube, with an air chamber on the side. It won't have any effect on the air flow at the velocity that it is moving through there. If anything, it is actually moving better with the resonator, as the "noise" is turbulence. And to create sound energy, the energy must come from somewhere. But either way, the difference is equivalent to bird droppings creating air drag. Almost non-measurable.

And that's the trick. 0 vacuum in the airbox means no work is done on the pre-filter side. The filter itself is the most restrictive part in the intake, creating several orders of magnitude more air flow resistance than any other imperfection in the design of the intake.

 

i had completely forgotten about those dyno numbers.

 

X2; it would be interesting to compare results.

 

It's such a cheap mod it's worth it to most to see if they get a difference;it's not like spending $200 on a K&N and getting zero results.

 

i've had mine capped for about 4 years now, i never saw or felt any difference after doing the deck plate. good thing you can just screw the cap back in and basically be OEM again without the giant hole in the airbox. i removed the elbow too, still no difference to me. but, i drive like a grandpa anyway and i wasn't out much money or time so i'm just like "eh".

 

This debate is never ending. Just do whatever mod makes you happy and call it a day!

 

This is the test that is sure to get some folks upset. Performance products is selling the K&N FIPK for $219. The K&N FIPK beats the stock box by .6 HP in 1st, 2.8 in 2nd, but looses to the stock box by 3.2 in 3rd for an average loss of .06 HP.

Now if you just cut open the front of the box you get 6.4 HP over the stock box for free or 9.6 over the K&N FIPK. Remember from the previous chart you will get basically the same results by removing the elbow as cutting open the box. I think this might be the way to go so you can pop it back in if you decide to go swimming.

Uh huh....

It does help. However, keep in mind...we all live at different altitudes...

Parker out..

 

i put some stickers, on the underside of my hood, Borla, K&N, schneider cam,BF Goodrich, NWOR, Downey,LcE, Eagle Globe & Anchor, thats worth at least 10 hp there.