How to increase performance/ horsepower?

I have a 2004 Dodge Ram 1500 quadcab with 5.7L Hemi. It has a free flow exhaust muffler and a K&N air filter which replaced the original filter. I purchased a Hypertech programmer III and after using it I have not noticed any increase in performance. What are some of the things I can do to increase performance and horsepower so I do not waste any more of my money?

Reply to
DAVE DAVIS
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1) Replace the entire factory exhaust with a "cat back" system, not just a muffler.

2) Ditch the K&N in favor of an intake system. The K&N filter alone will not increase HP, and may shorten the lifespan of your engine, depending on where you drive. An intake system will allow more air than just the K&N can deliver.

3) TB mods

4) headers designed to work with the cats and the O2 sensors, plus the exhaust to fit them.

5) If you have the AT, install a shift kit.

6) Larger injectors

Beyond this, any hp/torque increases will require internal work.

1) Porting the heads 2) camshaft 3) shave the heads
Reply to
Max Dodge

Been throwing money in wrong direction. Low restriction exhausr will reduce low and mid range torque not increase it. Part of the problem is the engine itself and its power band because its torque peaks above 4000 RPM. If you want to reall perk it up, install 4.10's with stock tires or some 4.56's if you are running 33's or so and some 4.88's with 35's. That will give you what you seek big time and likely improve town MPG too and about same (or better depending on current setup) on road in OD.

Reply to
TheSnoMan

None of this will improve part throttle and low RPM power and responce plus header add a lot of under hood heat too. YOu only have 350 cubes here and short of a supercharge nothing else but deeper gears is going to give hime what he wants. There is not magic bolt on for engine to fix this (again short of a supercharger)

Reply to
TheSnoMan

add the Cumins decal :)

Reply to
krenelka

Incorrect. Low restriction exhaust will allow better cylinder scavenging, which means more combustable fuel entering, and less spent gases remaining. Net effect: More torque in the lower RPM ranges, and better hp in the upper RPM ranges. If this were not true, headers would never have been invented.

This isn't a problem, most gasoline engines peak between 4000 and 4500.

And toss the fuel mileage out the window completely, while killing top end speed.

Around town maybe; on the highway, not at all.

Reply to
Max Dodge

Again, WRONG. Headers are designed to improve low end throttle response due to better cylinder scavenging. The only real worry here is tube diameter; too large, and the pressure wave doesn't aid in scavenging.

Rubbish. Headers on a 318, 305, 302, 289, 225, 231, 327, 340, 350, 351, All popular V6 and V8 displacements with the same or less CID, and ALL benefit across the RPM range from headers. Headers as a general rule give a 10% increase in power, and cost less than $1000 for a complete exhaust with headers.

No one claimed magic, but a supercharger is by far the worst mod for the dollar, although it gives the most results for any one mod. A supercharger will cost from $1500-$2000, and will require additional expenditures for engine management, putting the total cost between $2000-3000 dollars. Fuel mileage will go completely in the tank, but power will be incredible. Oh, and kiss your warranty goodbye.

Reply to
Max Dodge

Mine has a CuMMins....

Reply to
Max Dodge

Most gas engine do not peak there torque between 4000 and 5000 RPM and such a peak is kinda worthless in heavy SUV. Dodge would have done far better to have detuned the "hemi" to peak its torque and HP and a much lower RPM.

You also have a complete lack of understanding on the MPG issues here. I have been driving trucks for over 35 years now and used to drive them with 4.10 and 4..56 gears without OD. OD trannies are all the more reason to have deeper gears because even a 4.56 looks like a 3.23 or so in OD with it pretty tall for a heavy SUV with 31 or 32 inch tires and a

4200 RPM torque peak. Lower RPM does not always equal better MPG because it still takes same HP to move the load and a engine that has a high peak VE RPM has to work even harder as RPM drops and with RPM drop under load, so does engine efficency and MPG. We are not talking about a diesel engine that can be efficent between 1500 and 2000 RPM under load. TO bring the best out of a hemi in a heavy SUV you need deep gears or a bigger engine with more torque because the hemi does not have the low RPM punch otherwise because it lacks displacement.
Reply to
TheSnoMan

Max, ya keep it up and we are all going to have to read about a big block Suburban for about the 100th time.

Roy

Reply to
Roy

Yeah, its all about displacement in some people's minds.....

Reply to
Max Dodge

Welcome to the world of folks that want a real hemi... *g*

Might be best (and less expensive) to throw away the engine and put an old muscle car engine it... or buy a truck that's fast to begin with..

IMHO, the old Hemi was an engine designed to turn a car into a street rocket.... the engine that says "hemi" now is a great towing engine... YMWV

mac

Please remove splinters before emailing

Reply to
mac davis

Yep. My new Hemi is great for towing. Lots of torque down low. It is quick even when not towing. Far more so than my older 5.9L. Passing on the highway is a breeze with the new hemi. Still, it's no street racing machine.

Reply to
miles

I'm saying the difference will be negligible. My experience staring at the MPG disply on several vehicles tells me that this is generally true.

The question that arises is: Will the engine burn more fuel at WOT low RPM, or at part throttle high RPM?

I suspect each engine, and each atmospheric condition, each load, and each roadway, will alter the answer.

As such, it is reasonable to assume the engineers did their homework. Given the EPA/CAFE regs, customer desire, and simply good engineering sense, they came to the conclusion that gearing deeper than 4.10 is not a good choice.

Reply to
Max Dodge

I tend to think that mpg is best when at the lowest RPM that the engine doesn't struggle for the task at hand. If it starts to bog down mpg drops. Higher rpm's that produce wasted power is wasted gas too.

It is true that EPA/CAFA regulations play a big part of what gearing the manufactures sell. On the new Hemi Durango the 3.92 rear end is sold only on the top of the line Limited model. I didn't want to pay $1,000's more for options I didn't in order to get the 3.92 so mine has the standard 3.55 rear end. It does fine towing except for the dang shift points. Pressing the tow/haul locks out 5th but still allows 4th which is still OD (only 200rpm different than 5th at 65mph). At even a very slight uphill it needs to be in 3rd when towing but it's very difficult to get it to kickdown to 3rd and no manual method of selecting

3rd is available. Ironically sometimes when it finally does go into 3rd it shifts to 4th when I start UP a hill!! DC has issued at least 3 program changes that effect shift points but they seem to make it worse.
Reply to
miles

i bought used and could not afford the extra "M"

eather that or i was heavy on the eggnog last night when i typed my sig.

Reply to
krenelka

Me too... I remember back in the 80's I got my first add-on trip computer..

It changed a lot of my driving habits.... I remember that the speed limit was 55 mph and in 5th gear my Toyota pickup got it's best "instant-readout" mpg at about 68 to 70 mph... My guess is that was the "sweet spot" on the power curve...

I also used to go up a 5 or 6 block long hill on the way home... always put it in 3rd (5 spd stick) and kept the RPM's low, but not quite lugging, thinking that I got better MPG that way... I found that going up the hill in 2nd a slightly higher RMP than when I was cruising the freeway actually got much better MPG up the hill..

I should have known better, especially with all the 2 stroke bikes I used to ride, but sometimes you have to see the numbers.. *g*

mac

Please remove splinters before emailing

Reply to
mac davis

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