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2021 RST

Tom T H

By Tom T H
in Modifications, Wheels & Tires

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Tom T H Enthusiast

Tom T H

Posted
Posted

Hey Guys! I’m new at this forum & haven’t completely  figured it out yet. Got on here to see if I could get some what of an answer. I putting a 6” lift on next week with 35’s. I’m wondering what type of fuel loss I will get? I’m thinking 3-4 mpg loss. Also will I notice a lot of HP drop? 
  Another question is what’s the best programmer out there besides a laptop tune? It’s  a 2021 z71 ,RST, 4x4, 5.3L. Thanks in advance. 

Tom T H Enthusiast

Tom T H

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Posted

I’m guessing after all that. This site isn’t very active... it’s that I have not much clue on how to use the site or not many pep out there. Hmm.

Robby James Enthusiast

Robby James

Posted
Posted

Pulsar LT is the only option other than an ECU swap and tune, a little expensive if you don't have a bunch of extra truck money.

The Pulsar will drop DFM/Auto start and can also adjust speedo for your tire swap amongst other things.

 

Tom T H Enthusiast

Tom T H

Posted
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1 hour ago, Robby James said:

Pulsar LT is the only option other than an ECU swap and tune, a little expensive if you don't have a bunch of extra truck money.

The Pulsar will drop DFM/Auto start and can also adjust speedo for your tire swap amongst other things.

 

Would I be able to calibrate tire size with this? Also would it up the mpg?

newdude Senior Enthusiast

newdude

Posted
Posted

Higher up truck = less MPG.  3-4 is a reasonable loss estimate.

 

What kills it more than the larger tires is the aerodynamic change.  6 inch lift exposes the underneath of the truck to that much more turbulent airflow.  Stock the front airdam lets the air be directed down and under and around the front tires.  Add a 6 inch lift plus another inch or two going to a 35" tire, you throw that factory aero out the window.

 

You won't lose horsepower per say, at least at the engine.  You will lose performance because of the 35s which are bigger diameter, MUCH heavier than the stocks, and based on the 35s I've seen, are much more aggressive than any of the OE tires.  You are having to have the truck turn that much more rotational and un sprung mass.  

Robby James Enthusiast

Robby James

Posted
Posted
19 hours ago, Tom T H said:

Would I be able to calibrate tire size with this? Also would it up the mpg?

Yes on the tire size calibration, however because throttle sensitivity can be adjusted easily you likely would lose MPG from having too much fun TBH😀

  • Haha 1
TNTSierra Senior Enthusiast

TNTSierra

Posted
Posted

I’m sorry but “JACKING” up your truck six inches, and putting on 35 inch tires and you’re worrying about fuel economy!!  I just gotta 😂🤣😅🤣. But hey, to you it looks COOL!!  🧐🤔🤔
 

in all seriousness. You can do a hand held tuner from Diablo, but you must send in your ECU. Which can void your warranty. 
 

Here is a site to look at. 
 

https://www.diablosport.com/shop/predator-2-for-19-20-gm-gas-truck.html?SID=rqt9ug64krrgil0lrdds83kh27

 

Good Luck 

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