I started a post a while back about my truck not feeling like it had 345 hp. I have Hedman shorty headers a K&N drop in filter and just recently bought a Hypertech 50013 programmer. The programmer made it feel a little more responsive but not much of an increase. The rearend is 3.93. Its 4x4 which I know its not a racecar but I just feel like it should have more power than it does. The only time it feels like it has some ***** is right after start up when the engine is half way cool. But once it hits operating temps it feels doggy. Like there is obstruction somewhere in exhaust or intake, just makes a lot of noise but doesnt really go anywhere. I pulled the yellow wire with the green stripe to firm up the shifts on WOT and it did work great. Also I read on this site that its not good to run a programmer with headers because of the lean fuel mixtures and the temps could put a hole or burn a piston. Is that true? Im new to the hemi and any help would be appreciated!

 

Yeah, a program that advances timing combined with headers, CAI and other mods that increase air intake/flow can lean you out. I was pretty lean (not enough to generate a CEL though) when running the Superchips performance tune with my long tube headers, CAI, etc.

I used a 180* thermostat to richen it up a bit and it's within a fraction of stock spec now.

The Hypertech tune is not nearly as aggressive as the Superchip tune and doesn't advance timing as much, also shorty headers don't have near the scavenging effect (or the gains) that long tubes do, so I don't really think you're leaned out unless you have an issue going on.

First of all, your 345 HP is really about 250'ish at the rear wheels (thank the torque converter for that one). But that should still feel like plenty of power.

The obvious is tune-up and cleaning the throttle body (which if it's gummed up can kill performance and fuel economy).

 

Well what else can be done about getting more of that power to the rear wheels?

 

Have your cats checked at a local muffler shop just to rule out any restrictions.
Mine is a 2wd, but is pretty fast for a quadcab truck. I outran a little punk in a little lowered Honda Civic with a fart can muffler the other day and he was pissed
I have also outrun a late model Silverado SS from a 50mph roll.

 

Your probably going to looking at adding internal modifications to help produce greater rear wheel horse power, that's going to make a significant noticeable power. Stage two cam, stage two or stage three heads, custom tune...

 

Don't forget he's an 03 and therefore the Red Headed Step Child of the Dodge family.
There's a lot of expensive custom tuning or custom ground cam, to run anything other than a comp 260 or such in an 03.
Al.

 

Oh yeah, that's right! Maybe look into a Sparton custom cam. I believe most generation 3 ('03) 5.7's have to run dual combination tunes/tuners as well. One tuned for the TCM using HP tuner while running a CMR tune with the Diablo.

 

The question was not how to make more power at the crank, but how to get a higher percentage of the power at the crank to the rear wheels lessening the parasitic loss through the drivetrain.

Answer is a better, 3rd party torque converter...

Rams are about the worst, losing about 25% to the rear wheels, while the Nissan Titan is about the best, only losing about 14%...

 

Anyone heard of a good torque converter? That lessens that percentage?

 

Here's some good news for our stock transmissions.
A guy whose gone through neumerous rebuilt transmissions on another forum has now been running this stuff for several months now with zero issues.
Al

http://www.atsdiesel.com/ats2/productdetail/3069459272

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