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Hey guys im looking into getting 392 stock headers for my 2013 RT. Are there any advantages between the stock and the 392 stock shorty headers? Better air flow and more aggressive sound? Any extra HP unlocked with this mod and which RPM ranges do the shorties play the best?

Also whats the inlet and outlet diameters of the RT stock shorties and the 392 shorties? As i'll probably get catless mid-pipes too. Thanks in advance!
 

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I don't really think you will see any HP/TQ gain for swapping out headers on the 5.7. You've already opened up the exhaust according to your signature. My 2c
 

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Upgrading to the 6.4 shorty headers and mid pipes is a reasonable gain on a 5.7, especially considering you can find them used for around $250-300 all-in.

Some people will argue that for the trouble of changing them, you might as well go with long tube headers. Some guys really like the "ebay" hemi headers. Google that and see what you think. The collectors don't look too good to me on the ebay longtubes, but if they work, they work.
 

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Concerns of losing back-pressure resulting in loss of low end torque, especially that he's taking out catalytic as well? Just a thought.
 

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Concerns of losing back-pressure resulting in loss of low end torque, especially that he's taking out catalytic as well? Just a thought.
If he was doing 2"+ long tubes, then i could understand losing some scavenging. The SRT headers are the best bang for the buck upgrade on the 5.7L and he won't lose low end torque, even going catless.
 

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If he was doing 2"+ long tubes, then i could understand losing some scavenging. The SRT headers are the best bang for the buck upgrade on the 5.7L and he won't lose low end torque, even going catless.
Fair enough, assuming you have experience with your rig on this. What about OD of pipe? X-Pipe left in the system?
 

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"Needing backpressure for torque" is a myth that I wish would die a horrible death.

Header primary tube and collector diameter and length is all that matters. Anything in the exhaust system after that will show gains as backpressure decreases to 0.
 

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"Needing backpressure for torque" is a myth that I wish would die a horrible death.

Header primary tube and collector diameter and length is all that matters. Anything in the exhaust system after that will show gains as backpressure decreases to 0.

Correct, technically you need velocity and scavenging. The header is NOT all that matters - the remainder of the system still needs to have proper diameter, resistance and scavenging as per the design for the flow calculation design limits on exhaust pulses. There are always limits.
 

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A 2014 or earlier manual R/T should have the 2.5" exhaust size while the automatic has the 2.25" exhaust size. I would upgrade to a 2.5" exhaust if you have an automatic. Should be plenty of stock exhausts out there for cheap if you want to go that route.
 

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A 2014 or earlier manual R/T should have the 2.5" exhaust size while the automatic has the 2.25" exhaust size. I would upgrade to a 2.5" exhaust if you have an automatic. Should be plenty of stock exhausts out there for cheap if you want to go that route.
Sounds about right - my 07 Charger RT I upgraded the exhaust from 2.25" to 2.5" when I modified the exhaust, to maintain proper velocity :)
 

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If he was doing 2"+ long tubes, then i could understand losing some scavenging. The SRT headers are the best bang for the buck upgrade on the 5.7L and he won't lose low end torque, even going catless.
My logic here might be flawed, but I thought VVT adjustments can help alleviate this?
 

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To give you an idea, my R/T Shaker started at 331 RWHP with a Tune, 87MM throttle body and the mid muffler delete. After I had the shorty headers installed and cleaned up the intake, I hit 341 RWHP and probably would have hit more if I had upgraded the exhaust from 2.25" to 2.5". I left power on the table by not adding supporting mods. Anyway, I had a solid 18 RWHP increase throughout the powerband, but got knock above 5K RPM which killed the overall number.
 

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What about low end torque feel? Same? More?
 

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HP is nice but it's not what makes a car fast.
 

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Max torque prior to header install was 363 ft lbs at 4160 RPMs. Max torque after the shorties were installed was 377 ft lbs at 4320 RPM. Torque increased throughout the entire power band. Minimum of 10 ft lbs through the entire graph. My fuel/air was leaner than I liked above 3.5k (12.7 at one point), but I believe with a better exhaust and a Dyno tune, my former Challenger R/T would have hit 350+ RWHP and 380+ RWTQ.
 

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977223
 

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Thanks for info dude, solid write up and numbers post. Good to know.
 

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Correct, technically you need velocity and scavenging. The header is NOT all that matters - the remainder of the system still needs to have proper diameter, resistance and scavenging as per the design for the flow calculation design limits on exhaust pulses. There are always limits.
Not really. Less is more with exhaust after the collectors.
 

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Not really. Less is more with exhaust after the collectors.
Perhaps you should do a bit of research on this topic before you go littering our forum with generic disagreement without foundation.
 

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Oh, beleive me I have.

Show me one SAE document that shows a performance INCREASE from backpressure or exhaust velocity increase post collector. I'll wait.
 
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