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miles01

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A co-worker told me how he installed a K&N fresh air intake, exhaust, and programmed for 91 octain gas.
He claims additional 45 HP & Tq

I find this hard to believe, does anyone have real proof of this.
 

OC455

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Intakes and exhaust usually don't do much other than make different sounds, programming unless there was some other mods. Freeing up 45 HP & Trq...not likely.
 

G-Ride990

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Even if it was a custom tune and a full exhaust with catless long-tubes all the way out to the exhaust tip I think that number is pushing it.

No doubt he gained some useable power and drive-ability though.

I understand how some people believe that though. If you go to K&N's website or ARH's website and start adding up the numbers it says you will gain more than that. For example, ARH lists +35hp without a tune for a set of long tubes on a 1500 Hemi. Then K&N lists +10.3 hp gain with a cold air intake for a 1500. (obviously you are asking about a 6.4 but I just searched stuff for my truck real quick)
 

HandyCruiser

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The 392 is a real beast and already has great flowing heads, exhaust and intake. These aren't like the early 5.7 Hemi engines that left a lot of power untapped. If your co-worker is using a canned DS 91 octane tune or similar, he's getting all the advantages of a Pedal Commander plus the tuning to maximize it. So his 392 likely "feels" like it has a whole lot more power since it will jump when he presses the accelerator with his toe. At the RPM's for maximum horsepower, he's likely not gaining too much. But I imagine his truck is extremely fun to drive.
 

MADDOG

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My 6.4L responded well to intake (S&B), exhaust (Magnaflow muffler, resonator delete) and a programmer (Diablosport with a custom tune by Hemifever) with better fuel mileage, better sound, better throttle response and all over better driveability.

I don't think I got a 45 HP increase (maybe at the flywheel) but the sum of all the mods made for a much better performing truck.
 

HEMIMANN

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I'm same as @MADDOG - S&B CAI helped, I get slightly higher mileage. Maybe a little more torque pickup. The air intake is better than the 5.7L, but still not great. As a professional mechanical engineer, I can tell you that the factory intake was built for cheapness of manufacture, not optimized engine performance.

Th S&B cast smooth tube interiors without bellows, and uses larger bend radius, in addition to a larger air filter element area. They document substantial flow resistance lowering via bench test and publish it. Visual inspection to my experience seems to match their data reasonably.
 

928dennis

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I put headers on my 2019 3500 CC 4wd at 3000 miles, now has 52000 miles. I would say 70 percent of those miles is towing 12 to 13000 miles. I will just say the headers make huge power, I have put headers on allot of cars and trucks over the years but never had anything pick up this kind of power. the truck will get 9.5 mpg pulling 13000 pounds, I have crossed the US several times and got that. Empty on a long run of mostly flat roads I have got a little over 20 more then once. This truck has 4:10 gears, only other mod is a Air Raid panel filter. The exhaust from the headers back is all stock, I like how quite it is. I am sure a tuner would help also but may get to that if I don't wear the truck out first. People should just bypass the other over rated cold airs and catbacks and just go with the headers. When ARH says 35 HP at the wheels that can't be fare off, once again the power gain is huge and you will feel it.
 

Firebird

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I put headers on my 2019 3500 CC 4wd at 3000 miles, now has 52000 miles. I would say 70 percent of those miles is towing 12 to 13000 miles. I will just say the headers make huge power, I have put headers on allot of cars and trucks over the years but never had anything pick up this kind of power. the truck will get 9.5 mpg pulling 13000 pounds, I have crossed the US several times and got that. Empty on a long run of mostly flat roads I have got a little over 20 more then once. This truck has 4:10 gears, only other mod is a Air Raid panel filter. The exhaust from the headers back is all stock, I like how quite it is. I am sure a tuner would help also but may get to that if I don't wear the truck out first. People should just bypass the other over rated cold airs and catbacks and just go with the headers. When ARH says 35 HP at the wheels that can't be fare off, once again the power gain is huge and you will feel it.
This is just the kind of report I have been looking for! Have you experienced any heat issues towing with headers? I've heard folks say that they put off way too much underhood heat.
 

928dennis

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Here what I can tell you, You may get a check engine light, this is caused from the cats that were supplied not being efficient enough. ARH may have changed to a better cat since I went through a period of this after I installed them. Nick who owns ARH was great to work with, I was the first to put them on a 19 6.4. Also if you have a 4 wheel drive and are going to tow heavy loads up long steep grades you may want to wrap the collector on the drivers side with some header wrap. The header is getting so hot that they were starting to melt the front drive shaft slip joint boot, Also on the pass side where the hard brake line goes to the rubber line you will need to wrap the header and pull the rubber line back as fare as you can and wrap it. it is to close to the header. I just found this issue a couple months ago and contacted ARH and sent pictures. Nick says they will change the fixtures to fix. So ask if your going to go with the headers. I live in Colorado and tow up some very steep and long grades so the exhaust is getting very hot. Are they worth it? as for power they are amazing, you feel it everywhere. And the torque, under hood heat? has not been a problem. For the other issues it has been a ***** at times. There should have been more testing on the 19 and up trucks, things have been changed in the ecm area and the brake line department as per Nick. ARH is a stand up company and has worked with me on the problems but as for a new header with more clearence have not seen those yet. Just call and ask before you buy. Hope this helps
 

Firebird

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Here what I can tell you, You may get a check engine light, this is caused from the cats that were supplied not being efficient enough. ARH may have changed to a better cat since I went through a period of this after I installed them. Nick who owns ARH was great to work with, I was the first to put them on a 19 6.4. Also if you have a 4 wheel drive and are going to tow heavy loads up long steep grades you may want to wrap the collector on the drivers side with some header wrap. The header is getting so hot that they were starting to melt the front drive shaft slip joint boot, Also on the pass side where the hard brake line goes to the rubber line you will need to wrap the header and pull the rubber line back as fare as you can and wrap it. it is to close to the header. I just found this issue a couple months ago and contacted ARH and sent pictures. Nick says they will change the fixtures to fix. So ask if your going to go with the headers. I live in Colorado and tow up some very steep and long grades so the exhaust is getting very hot. Are they worth it? as for power they are amazing, you feel it everywhere. And the torque, under hood heat? has not been a problem. For the other issues it has been a ***** at times. There should have been more testing on the 19 and up trucks, things have been changed in the ecm area and the brake line department as per Nick. ARH is a stand up company and has worked with me on the problems but as for a new header with more clearence have not seen those yet. Just call and ask before you buy. Hope this helps
Thanks!
 
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