Acceleration

[Hemi Joe]

Lol ok, good to know. I gotta have my buddy go heads up with my RAM

If your buddy has a 2013 and older, you'll smoke him. 2014 it will be close depending on yours and his gears.

 

[GETARAM]

the 4000 rpm threshold... is that about where the variable intake shortens the runners up for top end power?

 

[Hemi Joe]

the 4000 rpm threshold... is that about where the variable intake shortens the runners up for top end power?

Could be.

 

[Hemi_Express2013]

the 4000 rpm threshold... is that about where the variable intake shortens the runners up for top end power?

I think that's about right. The intake has both short and long intake tubes with a valve/ butterfly that open and closes them depending on conditions. Go to Allpar.com, you will find the info you are looking for on this.


" The 2009 Hemi brought a higher compression ratio; higher-flowing heads, intake, and exhaust; and an active intake manifold that switches from long runners to short runners (by moving a flapper door), to optimize the engine for either better high-end horsepower or better low-end torque.

5.7 liter Hemi V8 engine cutawayVariable valve timing finally arrived, using a sophisticated yet relatively inexpensive computer-controlled, hydraulic cam phasing system. The camshaft, a hydraulic roller type with oil passages in front to drive the cam phaser sprocket, had increased valve lift. A new piston/rod assembly has thinner walls with a stronger-alloy pin.

All the ports were redesigned, with a raised exhaust floor; the new intake valves were roughly 2 mm larger than the first generation. Other upgrades are crankshaft structural upgrades, a dual-mass crankshaft damper, floating pin piston design, valve spring design, and oil pump capacity increase. The results of all this work are higher power, reliability, and gas mileage — and a power curve that is better than the original 5.7 Hemi in horsepower and torque at every point in the engine’s speed range, with huge gains in torque between 2,000 and 4,000 rpm.


Original is at The new Dodge Hemi V8 engine in full detail - 5.7, SRT8 6.1, and 392 6.4 http://www.allpar.com/mopar/new-mopar-hemi.html#ixzz2ckPUFBqv
Follow us: @allparcom on Twitter | allparcom on Facebook

 

[Hemi Joe]

I think that's about right. The intake has both short and long intake tubes with a valve/ butterfly that open and closes them depending on conditions. Go to Allpar.com, you will find the info you are looking for on this.

Cool technology.

 

[Arctic-Rodz]

Cool indeed, but did they intend to make it feel like a slug under 4k RPM? Is it just me or does it not feel like 407ft lbs of torque are in there down low? The HP is there and it is felt after that 4k RPM threshold.

I havent towed anything yet but will soon. Ill have to wait and see how the truck deals with some weight behind it.

 

[Riccochet]

That was definitely one thing I like about my previous Ecoboost F150. You mashed the gas and all of the power and torque was right there. Something my '13 Ram is lacking. Need a tune to remove all this torque management crap. My right foot is my torque manager.

 

[Hemi Joe]

Cool indeed, but did they intend to make it feel like a slug under 4k RPM? Is it just me or does it not feel like 407ft lbs of torque are in there down low? The HP is there and it is felt after that 4k RPM threshold.

I havent towed anything yet but will soon. Ill have to wait and see how the truck deals with some weight behind it.

There isn't, at the moment I can't find the dyno chart but most of the power of the Hemi is higher in the range. My new truck feels a lot quicker than the Ram, and that's because of all the torque down low. When it gets higher in the RPM range it doesn't pull like the Ram did though.

 

[Hornet]

I drove my brothers brand new 4X2 2014 Chebby 2 days ago,and man the 5.3 in that sucker pulls hard .
From the bottem end,the truck was very impressive
I wouldn't tackle one on a short run,maybe through a full 1/4 the Hemi might eat it,but on an 1/8 mile track,i think the new Chebby might have the Hemi's number if they're comparable trucks with rear gearing

 

[Hemi Joe]

I drove my brothers brand new 4X2 2014 Chebby 2 days ago,and man the 5.3 in that sucker pulls hard .
From the bottem end,the truck was very impressive
I wouldn't tackle one on a short run,maybe through a full 1/4 the Hemi might eat it,but on an 1/8 mile track,i think the new Chebby might have the Hemi's number if they're comparable trucks with rear gearing

I agree, and I have 3.08 gears (for economy), still amazed at the bottom end torque in this new motor. My Ram would've definitely beat it in the 1/4 mile like you said, when the Ram revs it pulls like crazy, but for general driving around town and highway this new 5.3 is great. I can't imagine how the 6.2 will be, they still haven't released official numbers for it.

 

[Hemi_Express2013]

The problem doesn't seem to be the engine at all or the rear end. I think it all comes down to the tranny. Between the torque converter and gearing is the issue. Let's face it, first and second gears are too high. Drop them in at 40 and it's not going to respond the way our trucks did in previous gens. 3rd is a monster in this tranny. The issue again is how the tranny manages the gearing. From what I've read, 3rd gear is used only under tow or manual control. Tranny selects what gear it wants under its condition at any point even in WOT. Put the manual at 4th and have a go at it.

 

[Arctic-Rodz]

I agree, and I have 3.08 gears (for economy), still amazed at the bottom end torque in this new motor. My Ram would've definitely beat it in the 1/4 mile like you said, when the Ram revs it pulls like crazy, but for general driving around town and highway this new 5.3 is great. I can't imagine how the 6.2 will be, they still haven't released official numbers for it.

Having bad a GM truck before, i know what you mean. Always liked how light they felt drivingaround town. My Sierra had the 5.3 with 3.73 Gears. That thing moved really well but yes, it lacked top end.

Ill see how this Hemi treats me.

 

[Hemi Joe]

Having bad a GM truck before, i know what you mean. Always liked how light they felt drivingaround town. My Sierra had the 5.3 with 3.73 Gears. That thing moved really well but yes, it lacked top end.

Ill see how this Hemi treats me.

Mine treated me well, you'll like it. I just needed a crew cab and wanted to give one of the new GM 14's a shot.

 

[Arctic-Rodz]

Let us know how youre liking that 14 Chevy. I didnt buy one because i didnt really like the new interior. They broke up the dash into pod like sections. I didnt think it flowed right.

Not to mention the price for a plane jane truck with nearly no options.

 

[Hemi Joe]

Let us know how youre liking that 14 Chevy. I didnt buy one because i didnt really like the new interior. They broke up the dash into pod like sections. I didnt think it flowed right.

Not to mention the price for a plane jane truck with nearly no options.

So far so good, I've had it a month now. I got a better deal on it than the dodge dealer wanted to give me, plus supplier pricing helped. The interior is really nice and everything's layed out well when your driving it. I didn't get an LTZ, but the LT is well optioned.