what is the purpose of changing a 6 cyl throttle body to an 8 cyl throttle body?

 

More airflow

 

/\ +1 on that.

the v8 tb has a higher CFM rating. Meaning more airflow, you will loose a bit of lowend (not noticable) for a large top end gain.. higher rpm wise.

 

I will be changing mine to a v8 tb as soon as my throttle cable comes in. I already have a noticable loss in low end due to my exhaust and stage one intake because the runners are shortened resulting in high end gains, but a small low end loss. After I get the TB installed I will update. Sometime in the spring I plan on installing 1.7 rockers and a limited slip differential with 4:10 gears to really get my low end back and help with acceleration. I am hoping to get the truck about 16 seconds flat in the 1/4. Right now my best pass was 17.4 with just a CAI and exhaust. After that I want to look into getting an SCT tune... then who knows. Really all i'm trying to accomplish is get my truck faster than my best friend's 02 RC 4.7 sport. right now he gets me by 2 truck lengths 0-60 lol.

 

should this be a quick swap or am i going to have to change anything other than the tb?

 

you will need a v8 throttle cable, one from a 98-03 5.2 or 5.9 will work