Dodge 5.7 Hemi V8

HendyPhoto · August 28, 2003

I just saw a commercial for the Dodge pickup with the 5.7 litre Hemi V8, and they claim it has 345 horses, is this right? More horses than the 8.1 vortec? I dont see how it's possible!!

Just curious.

MCourson · August 28, 2003

Im pretty sure it is 345 but it can't have near the torque of the 8.1. Also there was a link to a dyno report of the Hemi that showed low numbers and had a note that said maybe this is and over rated engine.

MCourson · August 28, 2003

Here is the dyno report.

chevy38fan · August 28, 2003

that dyno is on a 4x2 quad cab.. its like 5,133 lbs.. there's more than just 22% drivetrain loss.. weight has a LOT to do with RWHP.. a hemi like mine (RC SWB) is said to produce 270-273 RWHP.

chevy38fan · August 28, 2003

http://www.dodgetruckworld.com/forums/topi...732&q=hemi+dyno

good read there..

rico750sxi · August 28, 2003

How does weight have anything to do with RWHP? Also of note, the engine did only have 1600 miles on it.

FIRECAT · August 28, 2003

The thing that gets me with these new motors (Hemi or Vortec) is the high RPM that is required to make that HP. That Hemi needs to turn over 4300 RPM to make that HP. When is the last time anyone drove down the highway at 4000+ RPM?? Usual is 2000, maybe 2500RPM?? What kind of power does that motor make then??

This is the real reason I got rid of my 5.3 Vortec and decide against another gas motor, they just require too much RPM to make power. For everyday use, the motor is never spinning in the ideal operating range.

Think about it.

MCourson · August 28, 2003

weight has a LOT to do with RWHP..

How? I understand how weight and inertia effects straight up racing, but how does it affect RWHP when the vehicle is not actually moving like when it is on a chassis dyno?

BlackSilver · August 28, 2003

weight has a LOT to do with RWHP..

??????

Weight has no effect on RWHP. Zero. None. Zip-squat-nothing.

boen · August 28, 2003

I just saw a commercial for the Dodge pickup with the 5.7 litre Hemi V8, and they claim it has 345 horses, is this right? More horses than the 8.1 vortec? I dont see how it's possible!!

Just curious.

Dude... The Hemi will KICK ASS all over the 8.1!

FIRECAT · August 28, 2003

Dude... The Hemi will KICK ASS all over the 8.1!

Right.................

HendyPhoto · August 28, 2003

YOU THINK!! Bring it on Boen!!!

MCourson · August 28, 2003

Dude... The Hemi will KICK ASS all over the 8.1!

boen · August 28, 2003

I know.. I don't know crap.. Just wanted to see what ya'll would say.. I don't even own a truck.. Yet... But you see where I'm posting, don't you?

It's all good...

Dihappy · August 28, 2003

The thing that gets me with these new motors (Hemi or Vortec) is the high RPM that is required to make that HP. That Hemi needs to turn over 4300 RPM to make that HP. When is the last time anyone drove down the highway at 4000+ RPM?? Usual is 2000, maybe 2500RPM?? What kind of power does that motor make then??

Well, the Vortec makes more power (torque?) at low RPM's than the HEMI and probably gets more of it to the wheels.

As for high RPM's for driving, id have to say that they do get up there when you kick down into passing gear.

As for low rpm torque, well, if you need a truck for work then yes, youd be better off in a diesel. But i never "worked" in my truck, it was all fun