Mopar Ram Air Cold Air Intake performance ... issues

[murs-en-ary]

Hello,

I am new to posting in forums but I’m out of ideas and hope I can find some here. I just bought a new 2021 1500 limited 5.7 hemi etorque. I LOVE this truck however I added the Mopar cat back and Mopar ram air intake and now the truck drives different. I have taken back to dealership and they say it’s installed correctly and I talked with Mopar with no answers. I’m not sure if I’m the only one experiencing this. The performance has gone way down compared to stock.

With stock, you punch the hemi and it throws you back in the seat. I was getting close to 20 mpg highway going 80. Now after CAI the truck is slower to accelerate especially above 50 mph. I get 14 mpg highway going 60! It does not make any sense to me. I am going to have to go back to stock but I just don’t understand how a performance upgrade makes the truck worse. At the very least it should be as good as stock, not worse.

Anyone else experience this or know what to do? I am thinking of getting a programmer and chip to tune it but also don’t know what to go with assuming that will help it. The two I have seen is pulsar and Diablo sport trinity. Any suggestions?? Thanks in advance for all your help guys.

 

[crazykid1994]

Only reason I could see your mileage taking a hit is sensor left disconnected or driving harder but even 14 mpg is worse than I get tuned with long tubes, catback, and 6.4 intake manifold and lifted on 35s. I get 15-16 mpg hwy.

 

[murs-en-ary]

Yea it doesn’t make sense. Something has to not be right. Dealership said they installed correctly. I will look up information and try to see myself that they connected the sensor back.

 

[HEMIMANN]

I'll triple down on advice - something wasn't done correctly.

I installed S&B Filters myself on my 6.4 Hemi. It runs great, probably a little snappier from idle. Didn't notice significant mileage improvement. Still please with slight performance improvement.

I didn't do cat back - 6.4L has a garbage can-sized muffler. If anything, I'll do headers to get rid of constrictive smashed y-pipe.

I also get 15-16 mpg in my 2500 (weights 7,500 lbs or something like that). And that's only after I put AT tires on. It was 17-18 with AS tires before.

 

[seabrook]

disconnect your battery and turn on the headlights to drain the electrical system- then reconnect and see if that helps