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Which CAI to buy?

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I am looking for the "best" CAI on the market. By "best" I dont necessarily mean, the biggest HP gain. Im also looking for how effective/efficient and lasting it will be, ease of cleaning and looks too.

I have looked at K&N and their claimed 53.xx HP gain. It looks like they do not conform to the SAE J1349 dyno standard that Ford uses to compute the factory numbers for the GT500. The temperature and barametric pressure(s) are different, and it appears there was no retune done after adding the K&N, therefore making the engine run leaner, producing more power.

The FRPP grabbs 40HP with the SAE J1349 dyno standard test (plus a retune to correct the F/A ratio). I dont know the correction factors neede to accuratly compare these two filters, but it seems as if the k&N would do about the same as the FRPP when done at the same standard.

I have also tried to get info on the 2010 GT500 CAI or the KR CAI(which I guess are one in the same). That appears to be the FRPP CAI but with an added ram air that runs to the grill. It however, produces the same 40HP as the standard FRPP CAI. First, does anyone know why this is, and second, does anyone have a P/N for it and a price. It not in the latest FRPP (summer 2008) Brochure.

This is a quote from the FRPP summer 2008 brochure reguarding how dynos are done differently and how aftermarket companies forge their high numbers.

"There are two main types of chassis dynamometers (dynos) in widespread use today.
• An inertia dyno uses a large spinning drum that is accelerated by the drive wheels of the test vehicle. Power is then computed by
knowing the inertia of the drum and how quickly it was accelerated. Torque can then be calculated by knowing the speed of the drum.
• An eddy-current dyno absorbs and measures power by rotating a metallic disc through a magnetic field.

Without getting into which dyno is more “correct” under what conditions, and why, we will simply say that these two types of dynos typically
do not always give the same result even with all else being equal. It is generally not possible to accurately compare numbers from one type
of dyno with those from the other type of dyno. Each type of dyno has its own advantages and disadvantages, but as long as all the tuning
work is done on the same type of dyno, it doesn’t really matter which one is used.

With any dyno testing there is a need for correction factors that are applied to the raw numbers the dyno actually measures. These
correction factors are an attempt to correct for varying atmospheric conditions such as humidity, barometric pressure and air temperature.
The two most common standards are SAE J1349 and SAE J607 (sometimes known as “STD” on some dynos). How correction factors are
calculated is given in the “Crate Engine” section of this catalog. For this article understand that these correction factors will give results that
are different from each other, with SAE J1349 typically about 4% lower than SAE J607. OEMs will almost always quote J1349 corrected
numbers when advertising horsepower and torque. Some “tuning” shops will report STD numbers because they are always higher than SAE.
Be sure to ask which correction factor is being used when comparing dyno numbers!

Whenever comparing dyno results, always be sure that the numbers are corrected to the same standard. Despite these correction
factors, atmospheric conditions can play an additional role in terms of ignition timing. The correction factors account only for the change
in the density of the air due to atmospheric conditions and cannot account for things like engine borderline spark sensitivity. As inlet
air temperature increases, the PCM will generally retard spark to prevent detonation using the particular octane of fuel for which it was
calibrated. Correction factors cannot account for this because different engine designs can have different spark sensitivity and different sensitivity of torque relative to ignition timing. Basically this means that the closer the actual conditions are to the SAE J1349 standard
(77 deg F inlet air, 29.31 inHg barometric pressure), the more comparable the results are to those quoted by the manufacturer. Unless
otherwise explicitly stated, all horsepower numbers in the Ford Racing catalog have been determined by using the
SAE J1349 standard." :bigthumbsup
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I researched this for myself a year ago. The two options I considered were:

Option 1: FRPP #M-9603-SVT07 ($688.85 + S&H) 113mm mass air with inlet tube, conical filter and ProCal programmer to reflash the computer. These are the exact factory components used to up the 500 hp GT500 to 540 hp in the GT500KR (otherwise the motors are identical). They add 40 hp and are the exact same parts used on the GT500KR which keeps everything factory looking.

Option 2: Steeda 114mm mass air with inlet tube and conical filter ($389.95 + S&H) and SCT XCal3 programmer ($379.99 + S&H). American Muscle claims these two specific components used together add +97 rwhp to an otherwise stock GT500. The JLT 110mm mass air CAI and C&L 112mm mass air CAI are also available for about $399 each.

Stock GT500 has a 95mm mass air flow sensor. The 40hp gain for the FRPP is a conservative rating, with the exact same tune/program as the KR. All the others advertise "up to" various horsepower gains, which may require a custom dyno tune to achieve. The FRPP CAI will also yield a larger hp gain with a custom dyno tune.

The 2010 GT500 CAI is the same FRPP unit with an inlet tube that is bent more. They explain this as to align the filter behind the grill, but it is actually needed because the engine compartment is smaller in the area behind the headlights. Bends in air flow are generally not desireable; a straight path is better. The curved inlet tube for the 2010 will not fit in '07 to '09 GT500s (stuff in the way).

I chose the FRPP unit. Good hp gain while still maintaining the really nice factory look. Bumps your GT500 to the exact same hp rating as the KR and the 2010 GT500 using all factory parts. I'd say the only reason to buy any of the other three (Steeda, C&L, or JLT) would be if you were getting any of them in a package deal with a smaller drive pulley and the tune required for the increased boost.
I have tried to get info on the 2010 GT500 CAI or the KR CAI (which I guess are one in the same). That appears to be the FRPP CAI but with an added ram air that runs to the grill. It produces the same 40HP as the standard FRPP CAI.
The ProCal tool has just been updated to the ProCal II. Neither one does anything near what can be done with an SCT xCal3. The FRPP ProCal tuners are only sold as part of an FRPP upgrade package that requires a specific retune for the parts in that package to be added. The original ProCal tool only had one two-position switch: left for the stock program and right for the new program needed for the new parts. You only got a voucher for the ProCal tool in with the upgrade kit, since you had to register various parameters with FRPP (specific model number of your car's computer, rear gear ratio, rear tire diameter) in order for them to program the unit and then send it to you. The new ProCalII adds the ability to adjust for different rear gears and tires sizes yourself, but that's about it. There is no ability to change A/F ratio or any other engine parameter with the ProCal or the ProCal II.

A smaller pulley will indeed require a new tune. The ProCal tool would be useless for that. If you are defintely going to add a smaller drive pulley at some point, then you are better off with an SCT.
How does Ford's ProCal programmer compare to the SCT? Does it hold a memory for custom tunes? Can I change the A/F ratio myself with it for my own custom tune? I ask because I'm leaning towards the FRPP CAI package. I am going to follow up with a new pulley later. Does that also require a retune?
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