Hey guys I am a new owner of a 2004 Expy 5.4 with the heavy duty tow package, got a great deal only had 38k miles on her. I am looking at getting a boat weighing 8000lbs loaded including the trailer. I pulled a 6000lbs boat with no problem but I am thinking the extra 2000lbs may require a little extra umph for hills and such. Would it be worth the money to get an intake, cat back, and a programmer how much torque and hp would I expect to gain. Also should I replace the plugs right now there is only 44k miles but they are 10 years old. Thanks for the help.
04 Expy 5.4 increase engine performance for Towing
- Thread starter Skiffler
- Start date
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stamp11127
Full Access Members
Not meaning to sound like a chump, but it depends on how fast you want to go up the mountains.
I used to drive a big truck, we slow down going up the hills - it is a fact of life. I'm used to it so I just watch the temps and take it easy up and down.
Brakes are the big issue for me...
I used to drive a big truck, we slow down going up the hills - it is a fact of life. I'm used to it so I just watch the temps and take it easy up and down.
Brakes are the big issue for me...
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and how steep they are...I would think for what your explaining that youre looking for it to be effortless and that would require a supercharger to me...the intake...exhaust...programmer is minimum but will wake up the truck with the programmer being the biggest result and having the greatest impact...might as well upgrade internal parts in the engine if im correct in my interpretation of what youre asking...
mapitts
Member
Yes you will feel those numbers. What gear ratio do you have? You are looking for low end torque I would assume. With the '04 you have the PI heads. If low end torque is what you are looking for, I would make a tuner my first option. 5 Star makes a really good 93 octane performance tow / haul tune IMO. If that is not enough then you go from there. An exhaust set up may or may not be the way to go. If you open it up too much on a N/A engine, you will loose back pressure that is giving you your low end power. Plenty on the internet to read about on that subject. As far as an intake, to me, again IMO your stock airbox flows more than enough. I only run stock intakes and stock exhausts on both my Expy & my F150.
Coming from the Mustang world remember that they are looking for more top end power. The Mustang crowd is going the other way from us in the area of pwer that they want. I just got rid of a 2012 GT. It really did not come alive until around 3500- 4000.
Like stamp11127 said. Stopping your GVW would be another huge concern. 8000 lbs with just vehicle brakes is not going to be fun.
Coming from the Mustang world remember that they are looking for more top end power. The Mustang crowd is going the other way from us in the area of pwer that they want. I just got rid of a 2012 GT. It really did not come alive until around 3500- 4000.
Like stamp11127 said. Stopping your GVW would be another huge concern. 8000 lbs with just vehicle brakes is not going to be fun.
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Backpressure is a misnomer/fallacy. What you're after is exhaust velocity, to help with scavenging. This can be accomplished with an upgraded muffler and tailpipe, of an appropriate diameter. I was told by a tech at Borla that my 98 5.4 would respond well to a 2.5" muffler and tailpipe. I regularly haul a 3500lb trailer and can tell there's increased low end, top end, and I've gained 1mpg.
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Stamp and Mapitts, I agree stopping is a concern the trailer will have brakes. I think will start with the programmer. In my younger days I had a Chevy S 10 with the 4.3 v6. The tuner, intake and exhaust made that thing move especially once I installed the tuner.
american steel
Full Access Members
best ways to increase power output on a 04 truck is throttle body head port and a cam grind netting bigger lift just don't touch the duration.
headers. a tuner on this old of a vehicle with not so much power wont net you much gains infact in the real world tuners don't give much in HP.
going up and down hill will put strains on your brakes I would upgrade to a new disc and EBC brake pads.
I think I seen a comment about changing your GVW? that's impossible the only two ways of changing a trucks GVW legally is by the manufacture upgrading the axles/suspension and or taking weight off the vehicle by adding aluminum to the body. illegally add more rear springs. but in some states you can get heavy fines for this.
sorry to tell you but a tuner wont give you much.
worry about your top end if you want more power and torque and a CAI doesn't give much power. all they do is smooth out airflow through the intake to combustion chamber transition. the elements add little more air than compared to factory paper elements.
