Hello, i've spent alot of time reading about replacing the porous castech heads and i cant find my answer! Z71 with a 5.3 vortec engine with 110xxx miles. I need help deciding which heads to get. Im a newbie to cylinder heads so please be kind! Im not looking to increase horsepower but would love an increase MPG. I dont want to have to do a retune or use different length push rods. Is my only option the 862 head??

 

You won't pickup any real world MPG swapping heads. Maybe 1mpg at very best and you will need a tune to gain anything anyway. Lots of options, but if your looking for a stock replacement and no other changes then yes 862 is your best option.

 

Yep, what he said.

 

awesome, thankyou!

 

sell the truck and get a prius if you're looking for great MPG.