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Cold Air Intake and MPG Calibration Question

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Spyderpb3

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Hey guys,
I have a 21’ Power Wagon on 37’s with MBRP Pro Exhaust.

I’d like to add a cold air intake. I know there is always debate on whether they do anything or not, but there is a lot of research backing an increase to HP and MPG. So I’m going for it.

1) for those that have done CAI, what do you recommend and how did it effect your truck?

2) calibration. Does my truck need to be calibrated with the 37’s to read an accurate fuel efficiency and miles to empty?
I’m so confused because I used an app to check my speed, and it’s correct. Yet, the fuel efficiency/estimate to empty is definitely off.

Thank you all in advance

FE080549-971B-45F2-B12B-AEC1AA092175.jpeg
 
#1. You should take a look at your factory intake first. Hint, it is a CAI. ;)
#2 you need to program the truck for the size of your new tires, even if you do nothing else to your truck. ;)

Your factory CAI will provide all the air your motor can handle and then some. Now if you start modding the motor, or can find someone who can tune it, then you may need a different intake
 
Crusty old shellback said:
#1. You should take a look at your factory intake first. Hint, it is a CAI. ;)
#2 you need to program the truck for the size of your new tires, even if you do nothing else to your truck. ;)

Your factory CAI will provide all the air your motor can handle and then some. Now if you start modding the motor, or can find someone who can tune it, then you may need a different intake
Click to expand...
I knew it had a CAI but wasn’t sure that meant an aftermarket would still be negligible improvement. Good to know though!

As far as the programming goes, do you have any recommendations?
 
From what I understand if you have your phone connected to Uconnect your phone gets it's speed from the truck not GPS so you may want to doublecheck that. That is just what I have seen reported around here
 
I am not trying to talk you out of a CAI but I will provide my thoughts:
- Yes, a CAI will provide slight HP gains but the gains will be in the high RPM band and the engine will have to be under a heavy load (WOT) to see any gains. There will be 0 hp gains when driving around town or on the highway, towing a heavy load you may see a slight increase in MPG.
- Factory air filter will filter better than traditional oiled K&N style filters. If you do go with aftermarket intake I suggest dry filter vs. oiled. Search for a air filter video test performed by Project Farm on youtube.....K&N oiled filters are GARBAGE.
- As mentioned above your stock intake is a CAI
 
jenninr said:
From what I understand if you have your phone connected to Uconnect your phone gets it's speed from the truck not GPS so you may want to doublecheck that. That is just what I have seen reported around here
Click to expand...
Wow very interesting! I’ll have to try that again with Bluetooth off.
 
I used AlfaOBD to recalibrate mine. It also allows you to change other things as well. Like fog lights on with high beams, axillary reverse lights on while moving for those in calif and Moussri, and other things.

Also when doing the recal, you need to measure the actual rolling circumference of the tire at your normal pressure, not just go by the stamped dia and convert or go by what the manufacture says. ;)

My BFG 35's on factory rims at 37 PSI came out to just under 34". manufactures website says 34.5". So you need to measure to be accurate.
 
jenninr said:
From what I understand if you have your phone connected to Uconnect your phone gets it's speed from the truck not GPS so you may want to doublecheck that. That is just what I have seen reported around here
Click to expand...
So I just went out and tested this again while not being on bluetooth, and you were 100% correct. The speedometer is definitely off.
 
Crusty old shellback said:
I used AlfaOBD to recalibrate mine. It also allows you to change other things as well. Like fog lights on with high beams, axillary reverse lights on while moving for those in calif and Moussri, and other things.

Also when doing the recal, you need to measure the actual rolling circumference of the tire at your normal pressure, not just go by the stamped dia and convert or go by what the manufacture says. ;)

My BFG 35's on factory rims at 37 PSI came out to just under 34". manufactures website says 34.5". So you need to measure to be accurate.
Click to expand...
Thank you. I'm going to look into the AlfaOBD.
How complicated would you say the install and programming is? I've used a calibrator from RoughCountry on my Tacoma before, and that was fairly simple.
 
There are a few options for Speedometer calibration. AEV makes one, the AlphOBD and Ram Tazer. I did a Tazer and it been flawless but is probably the most expensive option. While you’re in there reprogram your TPMS psi as 65 or whatever is silly for this truck.
 
The stock filter setup is able to handle flow up to 800hp with the diesels so you will not see any gains at all with a CAI
 
I have the S&B CAI only because I got it cheap from a guy selling his Power Wagon. I installed it and haven't noticed any improvement (or decline) vs the stock filter. What I will say is that the filter on the S&B system is much easier to change than the OEM box with the long screws on it.
 
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