PTB and tune - definitely worth it! Probably exhaust also. As far as the CAI, save your self some money and do the resonator delete. It's basically the same thing :shrug:

 

Ram air yields better power gain over res delete with stock air box (jtr has 1/4 mile results). It eliminates the restriction in the system- the fender inlet.

If you have ever done any head work the TB p&p is easy.

Tune is definitely worth it. Even more so if you do it yourself so you can do it on your other/future vehicles.

Exhaust is worth it imho. I love the sound of my mbrp.

 

Exhaust worked for me, since I off-road frequently I still have my doubts about the air intake (don´t want more dust into the engine). Tune definitely is the most noticeable gain.

 

here is what you do, look in the top of the i4/i5 engine and drivetrain section, find supermods PTB and get it, he talors them specifically to YOUR truck. Then go to jagsthatrun.com and get yourself a header from there, it deletes the first cat and gives you a high flow header. next get yourself a standard K&N intake system. if you really want to get froggy you can get a flowmaster exhaust pipe. everything i mentioned is what i run and my truck HAULS! Also if you wannt to boost your mpg use mid grade fuel (89 octane) youll run alot better. hope this helps

 

What part of MI are you?

 

I'll second the CAI waist. Save yourself the three hundred bucks. I'll start running mid grade if I can get a few more miles out of it.

Sent from my PC36100 using AutoGuide.Com Free App

 

Its much better to delete the resonator and enlarge the fender opening. Most cai for this truck get air from the engine bay which makes it near pointless. Hot air = less power.

But yes, the tb/tune/plugs/syn oil/exaust is very worth it.

Most mods arent worth crap until you get a tune to use them tho, so ya gotta do all your powertrain mods, THEN get a tune.

 

okay, i thought it didnt matter if you ran regular tho. Because that's what the factory setting's are unless you tune it other wise.
I Live in Grand Haven

 

The P12 runs a low octane and a high octane spark table. I good tune will net you benefits as regardless of what you burn.

I was going to say that Lime-Swap is in Northville, stop by. But that's a trek for you.

 

Guys, the OP said he wants the best mpg, not power. While I do agree that a freer flowing exhaust and deleting cats along with a tune will get you better mileage and performance, I have to disagree with the thinking that an intake (aftermarket or DIY) will net you better mileage. Enabling your truck to suck in more air will force it to add more fuel, hence worse fuel mileage. Correct me if I'm wrong.


Sent from AutoGuide.com Free App

 

You are correct if the engine is at WOT, otherwise...

The engine will take as much air and fuel as it needs to perform as being requested by the driver. Say we're cruising at 70 mph on the freeway. With a restrictive intake we need 33% throttle to hold speed. With a new magical non-restrictive intake, we only need 25% throttle. The amount of power produced is the same. The airflow is the same. The mileage is the same.

 

With the stock skinny mini 235/75's and the mods listed below, I was able to get 25-26mpg summer time with my 3.5 CC 4x4. Winter was a solid 23.

With the same mods, I got 23-24 summer with 31x10.5's. Winter NEVER got below 21. I believe I did a res delete with this wheel/tire configuration.

With the same mods, I got 18-19.5 with 275/45r20's. Winter or summer. 3" maf, 2nd cat delete/modified intermediate pipe and deleting the rear o2 raised the mpg floor slightly.

MPG numbers were running 70-72 on the interstate running 91- highest we have available here. My cost per mile was cheapest buying premium over 87 and e10 89, which is garbage IMHO. Speedo was corrected via GPS after each wheel/tire change.

Ram air- 3" section of PVC and a hole saw is all that's required......

K&N drop in
efan
P&P tb by me
Denso Iridiums (my experience with NGK's didn't last as long)
Deleted pre-cat
MBRP
Granatelli COP plug 'wires'
Tuned by me

My truck beat the crap out of the stock 19-20mpg, and makes a LOT more power- part and WOT.

 

With the stock skinny mini 235/75's and the mods listed below, I was able to get 25-26mpg summer time with my 3.5 CC 4x4. Winter was a solid 23.

With the same mods, I got 23-24 summer with 31x10.5's. Winter NEVER got below 21. I believe I did a res delete with this wheel/tire configuration.

With the same mods, I got 18-19.5 with 275/45r20's. Winter or summer. 3" maf, 2nd cat delete/modified intermediate pipe and deleting the rear o2 raised the mpg floor slightly.

MPG numbers were running 70-72 on the interstate running 91- highest we have available here. My cost per mile was cheapest buying premium over 87 and e10 89, which is garbage IMHO. Speedo was corrected via GPS after each wheel/tire change.

Ram air- 3" section of PVC and a hole saw is all that's required......

K&N drop in
efan
P&P tb by me
Denso Iridiums (my experience with NGK's didn't last as long)
Deleted pre-cat
MBRP
Granatelli COP plug 'wires'
Tuned by me

My truck beat the crap out of the stock 19-20mpg, and makes a LOT more power- part and WOT.

What do you mean by res delete?


Sent from AutoGuide.com Free App

 

i seen about 1 mpg gain from cai, dont see why it seems far fetched to increase fuel mileage, the kn for I5's is dyno'd at 10.9hp gain, if the truck has less restiction and a few more hp it is less strain to accelerate and maintain speed. as for mileage, a ptb isnt going to do crap but increase your response. i would do intake, first cat delete, and a high octane tune, maybe exhaust if you want a lil sound, but the first cat delete will free up the engine quite a bit. i was getting 19 mpgs highway with 33"s with those mods. if someone knows what they are doing they can get about 13hp out of tuning the 3.7's. idk on the 4 cyls.

 

ok, with my I5 5speed 4x4 im gettn 19 this winter and im running 265/75/16s.so first in order of most gain in mpg's i need to do what?

 

Don't shift above 2500.

 

its also a 2004 3.5 with 128k on it

 

tried, didnt help

 

Start with cat delete, k&n drop in, and ram air to keep it under $75.

Ls1 fans and controller- maybe $100.

Iridium plugs- $35-40.

Exhaust.

Tune.

 

cat 1 or 2

 

Precat. In the manifold.

 

Thats really a good mpg for an 05 4x4...

 

will i still be able to pass smog in california with the first cat delete?

 

once again...

 

i suck at the search on here can someone be so kind as find a thread about this cat delte

 

On the main page, in the How-to section.

http://www.355nation.net/forum/how-...formance-maintenance/391-how-exhaust-manifold-catalytic-converter-deletion.html

 

That mod s worth it with a tune.

Fuckin pointless without one.

It may add a drone to your exaust. Some like it, some hate it.

 

even without a tune I picked up mileage and horsepower

 

Well I noticed a big drop in gas. Getting worst gas mileage then before my tune. Right now I'm at a half a tank and only gone 184miles. WTF and FML
Sent from my DROID RAZR HD using AutoGuide.Com Free App

 

That's usually where I'm at at half tank. I'm thrilled if I can get 200 miles in half tank, and another hundred before I fill up if I'm lucky....


Sent from AutoGuide.com Free App

 

Most of the mods you do make you run rich.

 

I had a tune and then after that I put my PTB on. I guess I need a reflash.

Sent from my DROID RAZR HD using AutoGuide.Com Free App