hp manifolds or headers?

[01MOPAR]

Is there any advantage running headers over factory hp manifolds?f I'm running a 3 inch exhaust system on my 440 ? Any difference in hp?

[41husk]

THere was an article a few years back, that listed the added power the HP manifolds added 5 hp over log and headers added 10hp over Log?  I think?

[dodge freak]

Think it be more than that, but it does depend on how big of a cam and how high it rev. On a stock cam and 5000 rpms that might be about right but go bigger on the cam and move up to 6500 rpm's the motor should make more than 10 HP with headers over  hp manifolds.

[41husk]

I have been digging around for the article, it was in mopar Muscle I believe and I am sure you correct there were several variables including exhaust size, cam and rpm.  I will keep looking.

[andyf]

My low deck 470 motor made 474 hp at the rear tires using HP manifolds and a MP .528 solid cam.  That was a sweet motor.  It had a nice idle at 900 rpm with a tiny bit of lump to it and a lot of bottom end torque.  Motor made more hp on the chassis dyno than a new Viper.

If you go to the Comp Cam site and look in the product article section you'll find an article called "Manifold Power" that goes into some more detail on my 470 combo.

[Chryco Psycho]

it depends on the cam profile used , if you use a 114 or 112 CL cam & manifolds it will make a LOT of power with manifolds , with headers the scavenging is better so you can use a 110 -106 cam CL & reap the benefits of the headers

[Ghoste]

If your combo needs a 3 inch exhaust wouldn't it also need the flow of headers?

[01MOPAR]

The 440 will have a small 270 or 280 cam and a duel plane intake ,stock 906 heads ,850 holley carb ,I have the 3inch flowmaster muscle car system  so the hp manifolds should flow well into this system.

[Ghoste]

Might even be too big.  I'd definitely go with headers.  Is that dual plane an aftermarket one or the stock unit?  Have you also given any thought to opening those heads up a bit?

[41husk]

I have headers on my 73, they were on there when I bought it.  I had headers on my 70 Challenger vert, and I had nothing but problems constant leaking tried double gaskets.  I just prefer manifolds.  I have had better luck.  I have friends who run nothing but headers and claim to have never had a problem. 

[01MOPAR]

Might even be too big.  I'd definitely go with headers.  Is that dual plane an aftermarket one or the stock unit?  Have you also given any thought to opening those heads up a bit?

weiand intake,Maybe a mild port on the heads.

[4402tuff4u]

it depends on the cam profile used , if you use a 114 or 112 CL cam & manifolds it will make a LOT of power with manifolds , with headers the scavenging is better so you can use a 110 -106 cam CL & reap the benefits of the headers

I can vouch for that! I'm running an Engle K58 cam 112CL with INDY EZ's and stock manifold and I'm very happy how my 68 R/T jumps and performs!!

[deputycrawford]

I have an article in Mopar Muscle Magazine that had a stock 383 they put headers on and found almost 25 HP. The scavenging effect is much better with headers. If its all out power you want then headers are your only choice. If originality is your concern then you can only run HP manifolds.