what can i expect with a 2.9L i-4??

[trophy_colorado]

i have a 2008 chevy colorado 2.9L i-4. stock it sits at 185hp, but with my 33" tires and a prerunner suspension, the lil 4 banger is having a tough time. i regeared the truck with 4.11's and now it needs a tune. im hoping that itll make a huge power difference aswell as get me some better mpg. eventually i wanna throw a turbo in it, so this looks like the best route. anyone got any idea what i can expect out of the V2?

[Taz]

A “huge power difference” and “better mpg” are often mutually exclusive pursuits. The software will certainly be of benefit to recalibrate your tune (speedometer & shift points) after gear / tire changes you mentioned.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
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With the addition of upgrades – headers, free flowing exhaust, cold air intake, cam, etc. – tuning becomes of great benefit to power output. On a completely stock engine, there is often very little “extra” power to be found via tuning. However, it does allow you to personalize how the vehicle operates – firmer shifts, higher shift points, etc.<o:p></o:p>
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Regards,<o:p></o:p>
Taz

[trophy_colorado]

i have a k&n cold air intake and a lightweight drive shaft. i just ordered an exhaust cutoff to bypass the cat (straight pipe basically). headers, cam, new servos will come soon, as well as a turbo, but only when cash permits. will i get better mpg just by changing shift points? or should i do the major mods before getting my tuner?

[Taz]

The point of my comment was to highlight one of the benefits of the software was to allow personalization of your vehicle. To make more power, requires more fuel, therefore a decrease in MPG. Changing shift points is to personalize the vehicle's performance, or your perceived driving experience - may or may not effect fuel mileage.

Keep the cat, there is very little power to be gained by not using it, and its also the responsible course of action. Sounds like you would like to do a lot to the engine - good idea to sketch out short and long term upgrades to ensure component compatibility.

On a computer controlled fuel injected engine, virtually any component upgrade will be enhanced with tuning.

Regards,
Taz

[ScarabEpic22]

Trophy, you cant just plug a V2 in and get the power you want, you have to build a tune off of the stock one. EFILive is going to be invaluable to you for changing the tire size and especially tuning for your turbo. Just swapping gears will help you get off the line, but your mileage is going to suffer. Remember you need 2 cams, the I4 is a DOHC motor and tuning for them will require a fair amount of dyno time, especially if you want to get the most power out of the exhaust VVT.