MPG MOD

Inquiring minds want to know...what is an "AFE filter"?

 

AFEPower.com

 

Instead of air filters, you're buying a "recharge kit"
Instead of air filters, you're increasing the dirt contamination in your engine, which scores cylinder walls and contaminates your oil.

Check it out.

Fresh oil change, run a paper filter.
Change oil at 5k.
At 10k, change the oil and send a sample to Blackstone.
Install a K&N on the fresh oil.
Change oil at 5k.
At 10k, change the oil and send a sample to Blackstone.
Look at the silicon levels on the report.

It will be high. That is dirt that has passed through your intake, and gotten PAST your rings and into the engine oil.

Will you see a failure because of it? Not likely since most people don't keep their cars more than 100k or so, but my '94 did start using oil pretty badly after 150k... I put in a K&N drop-in at around 30k.
I sold the truck with 225k on it... no clue if the new owner rebuilt the engine.

 

I'm still on the same kit I bought four cars ago. As for the engine failure issue, I've heard different theories, all plausible. One theory I heard was that the particles are so small, that they burn off in the chamber and that any particle large enough to cause an issue won't get through. I know mechanics who swear by them, and mechanics who think you're a moron to use them. Honestly, I'm not an engineer and not sure what to believe. I do know that I've had one in my wife's van for over 100k, and nothing would make me happier then to see that thing blow up. So really, win-win!

 

Random, I ussally get 22 MPG but ussally i put 10 dollars in two or three times before i let it drop to quater tanker then fill is that affecting my true MPG?

 

The secondary filter? That is the one in the "box" cover? I am guessing this would increase air flow.

Under 2,000 is the key ... no question about it.

 

Plausible or not, it increases silicon contamination in the oil, so the first theory that the particles burn off in the chamber is dead wrong.
Not only are they not burning off (silicon is SAND!), they are getting past the rings and into the oil.
Furthermore, some are indeed fine enough to pass through the oil filter and through the engine (otherwise the used oil sample would test "clean")... but without sending the filter in for analysis, we have no way of knowing what larger particles made their way into the oil and were captured by the filter. These are the particles that are going to cause cylinder wall scoring issues.

I've talked to techs who have pulled the heads off of an engine with a K&N and less than 50k on it. Original honing crosshatching is still present, and there's vertical scoring from contamination.

That the K&N allows enough dirt to cause damage is not up for debate. It is an absolute fact. How much that damage reduces the life of the engine is what is up for question.

Like I said, the majority of people will never see a problem because they don't keep their vehicles for more than 100-200k... but if you are planning on passing your Toyota on to a child or relative when you're done with it, the K&N is not doing them any favors.

The "secondary" referred to us the charcoal filter in the airbox lid.
Theoretically, it never sees dirty air so it doesn't have to be replaced... it just captures hydrocarbon vapor that back-tracks up the intake after shutdown.

 

i put a K&N in a 86 honda prelude.. been in there since 2000... 12 years later, well over 400k miles on the motor (current) and it still runs fine...

did i mention its owned by my father, a man who does not believe in oil changes and has only once cleaned the k&n?

 

Avoiding cleaning the K&N is the best thing you can do, it filters better the more clogged it gets.

Your example is proof.

 

The stock filter and pipes can flow far more air then the engine could ever use and deliver far cleaner air. Sorry the math just is just not there to make any difference except for noise and dirt.

 

+1

It's not a directly applicable argument on the Tacoma since the 4 banger and V6 airboxes and intake are different, but it always cracked me up when guys would put a "free flowing intake" on a Chevy pickup with a V6... which used an intake that was pretty much identical to the intake for the 5.7, 6.0, and even the 8.0.

But with the Taco, they are both drawing through the same fender opening and duct structure.

Trust me... the stock intake on the 2.7 is adequate to feed the 4.0... it can supply more air than any 2.7 can ever use, even boosted.