I have a 2008 gmc sierra short bed single cab with the 5.3. I have put on flowmaster super 40 series true duals headers back,airaid cold air intake, throttle body spacer, jet mass air flow sensor, and a edge evolution programmer and tuner and I was wondering if anyone had close to that set up so maybe they could give me a guest on what my horsepower and torque is at now I put all that on?

 

Look at JB 2004 as you can see I have none more mods than you.
First miatake, we should have put the trucks on a dino,fine the base,
then back on and see the difference.You be the judge ,fine the claimed
h/p for each mod then take off at least 25% to 50% of clamed h/p.
Example headers 10 to 15 h/p===I would say 12 h/p at best.
That is the way I did it,never go with the high side. We would be
just fooling ourselfs. What you think!!!!!!!!!!!!!!!!!!!!!

 

I have a 2006 4.8 with similar mods and I am dynoed at 346 hp, 353 ft lb of tq

 

MY GOD IF YOU GOT 346 H/P OUT OF A 4.3 WITH JUST SMALL AMOUNT OF MODS,I WILL BE AROUND 400H/P!!!!!!!!!!!!!!no way.
MY QUESTION TO YOU, DYNO JUST MOTOR OR AT REAR WHEELS.THIS IS HARD FOR ME TO BELEVE AT THE REAR WHEELS.

 

Thats practically impossible and i quite agree with JB here. Those are exorbitant numbers. Hard to believe maan!!!!!!

 

Well, first of all...the dude who replied first has a 4.8, not a 4.3....there's not a whole big difference between the two engines...yes, they are both small engines, but the one he's got does have two FULL cylinders more than the one you two think he has...so the 350ish range isn't out out of his reach by any means...the engine he has is very much capable of that and with what he has on there, it could very well be that.

 

With high mpg's all the rage now-a-days.... what kind of mpg increases are you seeing when installing these freer flowing intake/exhausts?



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i have a 99 gmc sierra 4.3 and i'm trying to figure out what's the best hp upgrades i could do for less than 800 bucks. it already has a so-so dual exhuast on it, and a K&N filter.