Just my opinion, but F/I is the better option here.
Your goal is 60-80 HP more, which you would get by swapping the motor, but you could easily get more than that from a blower or turbo setup, which would be just as reliable (especially at lower boost).... with the option of turning up the power with a simple tune and pulley.
Anytime you add power, there will be other components that may not hold up, like the stock tranny... this is something that should be looked at regardless of whch way you go - and if you do get a line on a tranny with a 6.2, may be a good option.
I just get the feeling you want a 6.2 to just say you have a 6.2... that is fine if that is what you want, just state that. as there are other options to get 'escalade' type power from the 5.3 you already have.
I am contemplating a turbo build for my tahoe - these motors are practically indestructible if tuned correctly - I have a procharger on my other car, which has been pushing over 500RWHP on a Stock bottom/heads ls1 for just about 75k miles (car has 99k miles). I have no doubt these motors can be bone stock reliable with the right FI setup/tune. Just something to consider.
The days of 'no replacement for displacement' are effectively over. Guy's are pushing 9's all day in with the litttle 4.8L's.... I know you keep saying you are not interested in the power side of things, just saying there is something to be said for getting fuel economy from a 5.3 just cruising, but power of a pissed off big block when you smash the gas.
Your goal is 60-80 HP more, which you would get by swapping the motor, but you could easily get more than that from a blower or turbo setup, which would be just as reliable (especially at lower boost).... with the option of turning up the power with a simple tune and pulley.
Anytime you add power, there will be other components that may not hold up, like the stock tranny... this is something that should be looked at regardless of whch way you go - and if you do get a line on a tranny with a 6.2, may be a good option.
I just get the feeling you want a 6.2 to just say you have a 6.2... that is fine if that is what you want, just state that. as there are other options to get 'escalade' type power from the 5.3 you already have.
I am contemplating a turbo build for my tahoe - these motors are practically indestructible if tuned correctly - I have a procharger on my other car, which has been pushing over 500RWHP on a Stock bottom/heads ls1 for just about 75k miles (car has 99k miles). I have no doubt these motors can be bone stock reliable with the right FI setup/tune. Just something to consider.
The days of 'no replacement for displacement' are effectively over. Guy's are pushing 9's all day in with the litttle 4.8L's.... I know you keep saying you are not interested in the power side of things, just saying there is something to be said for getting fuel economy from a 5.3 just cruising, but power of a pissed off big block when you smash the gas.