I posted this question in the General Tech forum before realizing it should have been posted here. I have a 2012 Tahoe LTZ/5.3L. I'm installing a K&N Blackhawk CA intake and have read that replacing the factory MAF sensor with an aftermarket sensor that provides more air would also increase gas mileage. This seems logical but opinions are about 50/50 for and against. I called K&N but realized that K&N is not going to recommend additional mods to realize the max performance of their intake. I have also been informed that installing this intake is only going to effect the sound of the engine and will do nothing regarding HP or gas mileage. Any thoughts?

 

You already have a cold air intake on your Tahoe. The engine sucks air from the passenger fender.

You might see a gain of 3-4 hp, but you'll never feel it.

With the government pushing hardcore CAFE standards, don't you think if a simple intake change could significantly impact mileage, the OEMs would have adopted it?

Lastly, the cone air filters that are commonly supplied on CAI kits are "less restrictive." This means they don't filter as well, and now you're sucking those larger particulates into your engine.

If you want the louder engine sound, go for it. It you're doing it for purported performance gains (increased power or better mileage), you're better off spending your money elsewhere - something like a Blackbear tune.

 

As I probably said before, check out Blackbear Performance. From what I can tell, it's the best bang for the buck.

Most of the CAI gains are at the upper end of the rpm band.

Of course there's always a Procharger or Magnacharger blower but then you're talking serious money. But then the old saying is "Money talks and BS walks".

 

Thank you for your reply. Your opinion is well noted but.....I don't think the manufacture would be a good judge of what is good and bad to increase power or address CAFE standards. I don't think there's any question as to the increase in power headers provide but the manufactures haven't made headers available in the showroom. I'm sure there are several aftermarket bolt on adds that would enhance mileage and/or HP over the factory yet the factory ignores these mods due to the already inflated cost of their vehicles.

Engine sound? I'm missing something regarding this comment. If the only difference I will experience by installing a CAI is a "louder engine sound then I pass. I have no desire to spend dollars on the sound of my engine. I'm simply looking for bolt on mods that will help the engine breath more air which logic supports an increase in gas mileage.

My concern is: will replacing the MAF sensor along with a TB spacer and a CAI have a positive effect on either gas mileage or HP?

 

I've done some research on the Blackbear tune and I will be sending my ECM next week. I understand the small increase in either power or gas mileage will not be realized at lower RPM's by simply installing a CAI but my question is will the addition of a performance MAF sensor along with a TB spacer and the CAI have a positive effect on either mileage or HP? The advantage of the K&N Blackhawk is it's a dry filter instead of the oiled filter.

I don't really believe a pro charger would have a positive effect on mileage but HP would go through the roof especially with a bottle and a two shot. However, I'm not looking for an increase in top speed I'm looking to create a more efficient engine. A gain in HP would allow the engine to operate with less effort which should be seen in mileage. Now if your talking about a .500 lift cam with ported heads you could be on to something but these mods would not accomplish my end goal.

 

Ok, now you really have me confused.

CAI - snake oil (and you might even damage your engine)
TB spacer - even worse snake oil
MAF sensor - the MAF sensor is a little probe that sticks into the intake stream to measure the volume/speed of the intake air. How does changing it impact airflow?



Here's a good thread from Benzworld that does a pretty good job explaining why CAIs like the K&N are a bad idea. Caution - science and evidence are used, not just internet anecdotes:

CLICK HERE

 

The performance filters, and spacers may have some added benefits in performance (they can also have adverse effects too) but the gains are really minimal compared to what you spend on them, you can also throw the under drive pulleys into the mix as well....
Auto manufactures are going to use what provides the most reasonable all around performance for both economy and power with reliability in mind.

Personally I think the filters and spacers and even some tunes are meant to do noting but make the manufacture of those items rich with your money...( I admit I have done the KN filters and headers and the like in the past, it was fun to do)
Real performance is going to involve the entire package down to heads that are ported and polished, headers, and intakes and MPG is not considered as part of that concern....
If you are racing at the strip every weekend, I'd say go for them and see what they do for you, but for a daily driver, I just don't see any benefits with the exception of a ECM tune for power OR mpg...

my 2 cents

 

Bottom line for better mpg is the driver's right foot. If mods could increase mpg w/ little or no effect on hp, the OEMs would be doing it due to onerous CAFE goals.

 

Exactly. The OEMs have picked the low-hanging fruit. Any additional real, measurable gains in hp or efficiency require expensive mods - porting/polishing, forced induction, new camshaft, etc.

My first car was an 81 Regal with a 3.8 v6. It was rated at 110 hp. My 2015 Taurus has a 3.5 v6 and it's rated at 258 hp. And the Taurus gets better mileage to boot.

How does Ford improve on that for their higher-end vehicles? Do they add a TB spacer or a cone air filter? No, they add a turbocharger.

 

For the money of some of those "performance" upgrades, you could use that same money on items like upgraded polyurethane bushings for sway bars and end links or even upgraded sway bars that will provide tangible handling improvements that will be used every day in every driving environment, making the current performance of the vehicle more manageable...