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Discussion Starter · #1 ·
Like the topic says, I did egr delete and a 4" turbo back, and I have my smarty at SW1(the fuel economy one). With the truck unloaded cruising at around 70mph I noticed the boost was around 10psi, which I didn't like at first because boost usually means using lots of fuel, but my milage was around 19mpg which I was quite happy with. Now, with two sleds on the deck, cruising around 70-75mph, my boost is hovering around 20psi, and it hits 30psi if I go close to 80mph. It still had plenty of power to hammer through the gears and get to speed, but seems to need a lot of boost to hold it's speed. Needless to say the truck gets around 9mpg like that. That is far worse than when it was stock. Stock you could notice the weight/wind resistance of the sleds, but barely noticeable in the power/economy of the truck.

I tried the smarty on SW2, and pretty much the same results.

Any tuning ideas or input?

For reference, the truck had stock gears with 35s, and sits at about 1750rpm at 70-75mph.


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boost usually means using lots of fuel

Now, with two sleds on the deck,

Any ... input?
Boost just means you have plenty of air to burn the fuel.

What are you referring to as "sleds" ????

Keep your foot easy on the throttle or pay the price in mpg.

Just as a guess you need to grow up.
 

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If you are using the CTS to read boost, then it is using the MAP sensor. It could be giving a false reading if it is dirty, and they do get dirty. Did you clean it when you did the deletes? if not, then do so, and see what difference it makes. There are threads on here with photos covering the procedure.
 

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There's a simple equation: increased power = increased fuel consumption.
My guess is you used to feel the wind and hills prior to the deletes and lived with it but now you have plenty of power to get up to speed and maintain it by using the additional power you've gained from tuning.

Since going from a 454 Suburban to the CTD I've found I have the same skinny pedal affliction as many do. I don't feel the wind or the hills but I do feel the power and the empty pocketbook.
Difference is I went from 5.5 towing mpg with the 454 to 10.8 mpg with the CTD so it doesn't hurt as bad.
 
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