Yoter

Ok I have heard from the guys that had factory airboxes & tubing & went to the K&N FIPK. That is an understandable performance gain but what about those of us with factory tubing & the modded air box. What difference have you guys seen in jumping to the FIPK? I am expecting a lot of change in acceleration over the next week. Tonight my tech buddy is starting on the 5.29 gear install. That should give me a 30% increase I was told. I am installing the FIPK on Tuesday & next weekend chopping the cat out to slip a straight pipe in. I am also going to bring my idle back up a bit being I lowered it coming into winter due to a high idle issue. So about going from modded air box with factory tubing to K&N FIPK should I notice much?

Blue

breakerfalls

I know this isn't really what your looking for, but when I had my Camaro back in the day and I went from just a drop in filter to the whole kit it made a lot of difference in my opinion. Now if that will translate from a V8 powerhouse to our sad little 6 cylinders... who's to say?

I'll be interested to hear what happens though because I know I can get more out of my Runner than just the cut out airbox and the drop in filter. I will spend the money on the kit if itproves to be better than that or the silencer removal mod.

-Keith

Cebby

So you are making Blue into an environment poluting powerhouse? Newsflash - you need backpressure (as provided by the cat/muffler) to make HP in the anemic 3.0.

Make sure you pour your oil and antifreeze into the storm drain too, while you're at it.

breakerfalls

Is he keeping the muffler in? I don't know alot about exhaust, but I thought the backpressure was a result of a decrease in the size of the pipes. Even if he removes the catalytic converter, won't he still have to drop from the 2.5" pipe coming down the headers to the 2.25" most people have for mufflers on 3.0's? I don't think he said he was taking off the muffler too, and I would assume that would be the point of the transition.

Also I thought that long and straight tubing helped create more backpressure. That's why it's ideal to run the exhaust out of the back rather than behind the tires like from the factory. Granted that if you are doing any wheeling a pipe sticking out the rear is a pretty bad spot to have it.

Ehh... I don't even know what I'm talking about...

-Keith

Waterboy

I think you will see a difference with the FIPK. The kit removes the 90 degree bend in the factory tubing. Not sure how it is all going to work out with your BL.
About the cat removel. Every one I hear that has done it ended up going back because it didn't add power and caused idle problems. From what I hear our cats don't add excessive back pressure (that's our stock manifolds ).

amusement

Straight pipe mod the cat

Tossing aside poor performance and legal issues it doesn't make sense lowering the back pressure when the EFI system was designed to perform with it on.

But, go ahead and prove me wrong.

FIKA increased my 3VZE performance in the low end and throttle response. A 5% increase MPG was gained.

Yoter

The only difference between the K&N FIPK & the straight pipe mod you see here on YT is price. I could do it for $20 in parts but dont want to. I am going to buy the FIPK because it has proven performance from what ive heard. Blue

Yoter

[QUOTE=Cebby]So you are making Blue into an environment poluting powerhouse? Newsflash - you need backpressure (as provided by the cat/muffler) to make HP in the anemic 3.0.

QUOTE]

Now calm down Cebby & breathe in & breathe out. Your gonna give yourself a heart attack. It already guzzles gas and the way I see it if my rig is struggling to perform and guzzling more gas than need be I need to modify it. I am doing so by giving it more flow by removing the cat. I have been worrying that the cat is clogged and this will cure that worry. There are no air pollution laws where I live. By removing the cat that is maybe 2.5" pipe & replacing it with 2.25" pipe how is it losing back pressure. Now if I were putting in 3" pipe that would be a loss in BP but I am not. The muffler is still in tact so that also is not allowing me to lose any BP. And with your "Make sure you pour your oil and antifreeze into the storm drain too, while you're at it. " remark I have never done that nor will I ever so get your facts straight please. Blue

Yoter

[QUOTE=maherj] Not sure how it is all going to work out with your BL.
About the cat removel. QUOTE]
My factory air box was to tall after I lifted the body the three inches so I had to chop three inches off the bottom end. I ended up cutting the rim on the bottom part of the air box off so that what I had was a ring with clips. It worked good adding HP but the bend is the next issue. Yeah body big body lifts & air boxes dont get along to well. you have to make them get along. Blue

Cebby

So will replacing with a free-flow cat (by free flowing I don't mean hollowed out either)

We all can only hope this changes since responsible choices for the environment appear to need to be forced on the public. Funny thing about air, we all share it.

I'm no engineer, but I've read alot of testimonials that removing the cat degrades performance.

That statement was a little thing called sarcasm. I'm certain you have never, nor would ever do such a thing. My apologies for the insinuation.

Tacoma Dude

Save yourself the headache and the flaming and just leave the damn things in.

Yoter

Oh..............

2001Millrunner

ben for the love of God leave the cat in. fumes will kill you if the cops dont bust you for it. and as far as air intake, unless it's a turbo or V12 it's not gonna make a difference(not that you can tell anyways) Sound would be louder, I put my intake silencer back in and deck plate in because the sound was too loud.

jruz

You need to put in some headers, if you haven't already. You'll not be gaining squat with putting a fatter pipe in the exhaust...keep it stock. The proper size of tube is determined by the displacement of the engine, yours has not changed...has it?

My experience with the FIPK (on my 2.7L)...only helps on the highway (and higher RPM range). The headers I put in, helped a great deal for in-town and off-roading.

PS: Don't gut the cat...why do you want to give cops another reason to bust you?

Jim

doink

what exactly is "rear"

cubuff4runner

Although many cities don't require "cats" they are still required federally. According to Environmental Protection Agency's website it is illegal to ever remove a catalytic converter on any car, regardless of the age of the vehicle. There is also a $2,500 fine for individuals for tampering with it. If you take your car into a shop, they are required by law to repair it the way it is supposed to be (with the catalytic converter).

Dr. Zhivago

Yep, Cats are a federally required item and a hefty fine awaits you if you remove one. If you want a free-er flowing exhaust, get a Random Technologies or CarSound catalytic converter. They don't rob you of any HP and you'll still be legal.

My .02
G

Bumpin' Yota

I have the Carsound Free Flow Cat. It helps a LOT, but I also have the FIPK intake. The 2.25" cat back with v8 muffler coming tomorrow. (v8 to keep it quiet yet still have "hiflow"...)

As for backpressure...

4 strokes do not need backpressure, 2 strokes do.

Ever wonder why the top fuel draggsters have a single 6-12" long pipes? It's so that the exaust wave actually generates a scavanging effect when the exhuast valve is opened. The length of the pipe determines how much scavange there is or how little...

Yoter

lol oops READ. Like he red wut I tiped. Me no no how to spel. LOL I was frikkin tired that night. Cebby stop losing sleep. I have not YET done the cat mod. I MAY be a goody goody and keep it legal and not piss off everyone. I am sorry you lost sleep over my economic terrorism. JOKE!

Tacoma Dude

bleh... I had something here but forget it. Not worth the hassle