Cardesign

Im a little confused in this one. If the deckplate increases your airflow which will call for more fuel doesnt that decrease your gas mileage?

I will be driving from NY tO CA very soon and want the best possible gas mileage. Im wondering if the deckplate mod would pass the emmisions inspection in CA.

Rick F.

Oh, boy. This one can open a can of worms. OK, here's my take on this:

By opening the airbox you're allowing the engine to breathe more freely and supposedly not have to work as hard (make more efficient use of the fuel?) to accelerate. If you could drive EXACTLY as you did before installing the deckplate, you MAY noticce some improvement. HOWEVER, since we're all power animals and since the deckplate mod does 1) add some noticeable seat-of-the-pants pep and 2) sounds awesome as you approach WOT, I don't think anyone has been able to restrain from getting on it more than usual. In my experience. my mileage is about the same as before the deckplate mod but my grin is much wider!!!

Cardesign

how necessary is it to install the amsoil filter with this mod?

X-AWDriver

An Amsoil or K&N will allow more air flow but you can use any filter even OEM.

Rick F.

I installed the deckplate mod sometime in late 2002 and then the Amsoil filter about a week later. I ran the Amsoil filter for about 2 years and replaced it with a paper filter about 5 months ago, only because I was getting tired of the check engine light coming on and cleaning the MAF about every 3-6 months. Seems like no matter how much oil I squeeze out of the Amsoil filter I still get the MAF crapped up. I notice no performance nor mileage difference between the Amsoil vs. paper with the deckplate open.

Cardesign

Rick F...thats exactly what i was thinking. NO sense in messing with a $600 MAF for minimal performance. Now i just have t find out if its legal in CAlifornia.

RobT2k

Mine passed smog test fine with the deckplate. I put the plate in, not sure if they even noticed it, or if it would have tested any different with it out.

California is strict on the emissions, and you have to score good numbers, but they dont do an "inspection" like I've heard some of the states in the east do. They do a basic once over and make sure no check engine lights are on.

rimpainter.com

I have ran the deckplate mod on two different 5VZ-powered vehicles for the past 4 years and never had a CEL due to over-oiling the filter.

Sounds like operator error.

jacksonpt

Here's my take on it... The deckplate mod has no significant affect on anything, at least not as far as I can tell from my spot in the driver's seat.

2001Millrunner

I agree, nothing really changed, just a bit louder, then ISR mod changes EVERYTHING(louder). Only thing really you have to watch out for would be lead foot.

Darren

I agree with Jackson and Ray. The only thing mine did was add noise. There is no power gain, and no difference in gas mileage with it open. If given the chance to do over, I definitely would not have. A nice, clean OEM air box is certainly better than one that gets chopped up. At least it didn't cost much to do. For the life of me, I cannot understand all the hype surrounding this mod. As with everything else, though, I guess each truck is different and your mileage may vary.

FilthyRich

Ditto

Tacoma Dude

Wouldn't altitude be a factor as well?
I'm pretty much at sea level being in San Diego but some of you guys are up a bit higher...

MTL_4runner

The airflow is improved but you may not notice it as much in regular driving as you might towing or going up a steep hill.
I also added an Amsoil filter at the same time so it is tough for me to tell what is deckplate, what is air filter.

ewarnerusa

ditto.

I did do this on my old 2.7L before I got the V6, though, and I liked it then. As far as my V6 goes though, the deckplate is permanently closed. I have an extra 5" deckplate in my garage, too, if anyone is interested in it.

Jason B

This mod is only noticed really at WOT at 55mph+. It does add a bit more kick. Normally, the 4Runner doesn't do much of anything when you floor it at 70mph, it just stands there. This mod will help you out in that area.

I've driven friends trucks without the mod, and if I had to guess, it adds maybe around 3-4 hp. Now, if you are running 33's, etc, you probably won't feel it.

I've had amsoil filter and deckplate in for over 4 years.

RockComa

So why not just leave the top of the airbox off instead of cutting and drilling

Cardesign

thanks for all the replies guys. Im still not sure what im gonna do yet. Im getting 16.5 mpg right now. I just installed a new fuel filter today(dirty ass job) and I'll see what that brings. I guess the deckpate might help considering im gonna have two turtles on top and my truck filled with crap on the way out to CA. Not towing anything though.

MTL_4runner

Good point Jason.....the more open the throttle plate is, the more this mod will add to the response of the engine. You are removing restriction to airflow so when demand is low (ie not to hard on the gas), restriction won't matter much, but when demand is high such as max power at WOT or close to it, the restriction does become a factor. The goal is to minimize the difference in pressure between the air coming into the engine and the air in the intake tube.

Cardesign

so have we concluded that it WILL NOT hurt gas mileage? I just fig increase of power meant more fuel consumption.