I just installed an Airaid CAI that does not require a tune. It's advertised as adding 11hp. I'm skeptical of that claim. Has anyone experienced any hp increase without a tune?

Also, it seems like it's louder now...no complaint there. Is that possible or is it just my imagination? I have GT500 axlebacks and the sound tube was deleted last year.

As always, thanks in advance.

 

Can you really feel 11HP?
Probably not.
Your actually rear wheel HP may be even less than that.
When I first put a K&N intake on my 4.6L it was advertised as a 15HP gain.
The dyno showed a solid 4HP at the rear wheels.

 

Tom, here's my take on it, which may be wrong but there's always a chance.
If your CAI doesn't require a new tune then the MAF is probably the same as the stock.
The sound difference could possibly contributed to the open airbox now. I believe that unless you have a cai with a new MAF and some kind of ram air to it, the actual hp difference will be minimal.

 

Kinda figured that Darren...hence my skepticism about the power. But even if the louder sound is only in my mind, it helps to block the other voices in there.

 

This is true for sure, The ONLY reason a new CAI must have a tune, is because the MAF metering section is larger diameter than stock. The MAF "transfer function" must be recalibrated or the computer will think there is less air coming in than there actually is, causing the computer to command less fuel than is really needed for the air coming in and the car will run lean.

But that does NOT mean that there can be no gains with a no-tune-required CAI. There are other sources of restriction, other than the diameter of the tube, that can be reduced with a modified intake. That said, I agree the gains are probably minimal.

For sure you hear more intake noise with an open intake. Part of the reason the factory intake is enclosed is to reduce noise. But some people swear it also makes the exhaust a bit louder; I don't really understand that; maybe they are really hearing intake noise and thinking it is the exhaust.

 

Agree with Darren. I had an Airraid too before, when I was NA. Didn't notice much change in "seat of the pants" dyno. Not saying there wasn't, but I didn't notice a difference.

Sound yes. Since I slapped on my CFM CAI, not only is the whole system louder, but I can clearly hear my Maggie whine now. Night and day. I love it for the sound gain alone.

 

When I still had my 05 GT, I started out with the Steeda 90mm CAI along with Doug's/bamachips 93 race tune.. After the car was checked on the dyno, I gained a total of 17 RWHP over stock.. Therefore IMHO, it's the tuning that provide the most power and torque gains and not from the CAI..

Just for the record, I don't care how large the MAF is over stock, as the bottom line is this.. Unless the stock upper intake and heads are also upgraded, the OEM units are only capable of taking in the amount of airflow for which they were originally designed from the factory..

So what good is really adding a huge MAF tube if the stock heads/intake aren't able to take advantage of the additional airflow to begin with, as It would be just like trying to suck a large volume of air through a straw lol.

With that being said.. Unless you also plan on upgrading to higher flowing heads/upper intake, adding a large diameter CAI on a stock 3v-4v motor is pretty much nothing more than just overkill and useless as far as I'm concerned

 

Doubtful there is anything to add without a tune... The tune re-scales the MAF transfer function to account for a larger diameter intake tube.

There is added intake tract noise because the flow path is straighter, and the factory tube has what is called Helmholtz isolators (those funky looking boxes molded onto the tube) that cancel certain harmonics/sound.

 

That is a HUGE generalization and not entirely true (even otherwise stock..), although I do see it parroted on here quite a bit like it is the Gospel of the Lord himself though.... Makes for good drama I guess when someone asks about a CAI.

 

It's simple physics and not some huge generalization as you claim.. Why do you think the engineers over at Ford designed the stock MAF size at 79.5mm for the 4.6 3 valve in the first place ? Because of the stock 3 valve's intake ports, that's why..

Just as I mentioned earlier, the stock heads are not high flowing when it comes to intake airflow and by adding a huge CAI tube isn't going to increase the volume of airflow for which the stock 3 valve's intake ports are capable of taking in..

Therefore unless you also intend on upgrading to high flow heads and upper intake, anything above 90mm MAF is considered overkill on a stock 3 valve engine..

As for drama is concerned.. I suppose that according to your expertise, the engineers over at Steeda are also wrong, right ? And while we're at it, let's also throw in Doug who was the founder of Bamachips and Lee Bender founder of C&L performance for providing me with inaccurate info as well

Not entirely accurate, as the tune also re-maps the air/fuel and spark/timing tables!

 

Wow, just wow.....

Seems as if you don't even own one of these newer cars? This is not an '05 3 valve or old school 4 valve, not even remotely similar.

Re-scaling the transfer on the Copperhead ECU also indirectly adjusts fueling, as there is no base fuel to adjust on the 11+ cars. There is little to adjust timing wise as you aren't creating a increase in cylinder pressure (a drastic one anyway...). The knock sensors on these cars work good, and when setup correctly in the tune, can dynamically add or subtract a few degrees of timing on the fly- did you even know that? Plenty of tuners (I've seen and read their files, I tune myself...) don't even touch the timing curve for a simple CAI, for a lot of tuners there is more harm than good to do. Where do you get your knowledge from? I get you have a HUGE post count and maybe you're are a well thought of member on here and a great guy, etc... But your knowledge on the 11+ cars is WAY off, and you should probably stop giving technical advice about them since it is pretty misguided....

I'd keep going, but obviously would be wasting my breath. You have the high post count, so obviously you are a resident expert around here....Keep repeating and restating misinformation, and that will make it more true....

<I give up>

 

 

The basis physics is that all fluid flow is driven by pressure differentials. The bigger the pressure differential, the more fluid will flow through any given hole (per unit time).

The pressure differential that makes the air flow in to the cylinder is the pressure at the outside of the ports, less the pressure inside the cylinder. During the intake stroke, you have near zero pressure inside the cylinder. If you can increase the pressure reaching the outside of the heads, you increase the pressure differential, and more air will go through the ports into the cylinders.

The pressure reaching the outside of the heads, is atmospheric pressure less the pressure drop through the intake. So, if you can reduce the pressure drop through the intake, you can increase the pressure reaching the heads, and push more air/fuel mix through those holes, without making the holes bigger.

That's the point of changing the intake . . . to reduce the pressure drop . . . and there are many things that contribute to that; the diameter of the tube and the size of the filter being two of them. So yes it is physically possible to get more air through the intake ports by changing the intake design.

That said, whether and how much the aftermarket intakes actually do that, is a different debate.

 

I'm with you. All I originally asked was if a little extra power could be gained from an un-tuned CAI and if the CAI could make make mine louder!!!

 

LOL . .. and the short answers are
Yes (but probably not as much as you can with a tune)
and
Yes (but it's probably mostly coming from the intake, not the exhaust)

 

That's right.. I own a 2006 4.6 3v and not the 11-16 5.0 Coyote 4v which is posted in my signature..

To answer your question.. No I was unaware of the differences you pointed out between the 4.6 3 valve and 5.0 Coyote 4v and assumed the basic architecture remained unchanged..

As I mentioned in my previous response, I obtained my knowledge from Doug (formally from Bamachips) and from Lee Bender, founder of (C&L Performance) However I failed to mention the knowledge that I obtained from them, apply to the 4.6 3v and not the 11-16 5.0 Coyote 4v..

Therefore I stand corrected for not mentioning that in my previous post..


My post count is irrelevant, although I try my best to provide support for my fellow members.. However whenever I happen to be in the wrong, I always have the courage to admit it..

First off ! I am far from being an expert and as I just said.. When I'm wrong about something, I'll be the first to stand up to the plate and admit it..
So once again, my post count has nothing to do with it, as I'm just a classic car enthusiast who happens to enjoy sharing his passion with others who also share the very same passion towards classic cars and nothing more..

With that being said.. I've revealed to you 3 times in this post that I was in the wrong..
So once again, I take full responsibility by admitting my mistakes for posting inaccurate info in my previous response to your post in which you were spot on from the start..

And just for the record, I also stand corrected that my technical knowledge for the 11+ cars is way off and will therefore stop giving tech advice..

As the last thing I'd ever want to do, is provide folks with inaccurate/misguided info..

So in the end, you can choose to either accept my apology or reject it.. It's your choice !

 

John, thanks for taking the time to explain everything.. As I now have a much better understanding how pressure differentials affect airflow.. So therefore once again, I stand corrected..

-Rocky

 

You're welcome . . . . and now I stand waiting to be corrected, LOL!

 

 

Also let's not forget these cars have Variable Cam Timing for both the Intake Valve Opening and Exhaust Valve Closing. Stock these cars have their IVO and EVC timing set for maximum efficiency, not optimized power.

Increasing the Intake allows different VCT timing events to build more pressure and therefore utilize that larger airflow.