Okay so if I get a custom tune from Wheatleyand Flowmaster exhaust, what kind of true dyno-provable increase could I expect to see out of the 4.8L? I'm thinking atleast 20HP to the wheels difference but is this unrealistic?

 

no that sounds about right but i suggest opening up the air intake at the same time to better results. remember how you can you benefit from opened up exhaust if you dont open up the intake?

 

Well I've been thinking about that and I don't know that you could benefit from a CAI. I already have a K&N air filter in my stock air filter housing and the factory air intake is designed to take in cold air just like most cars. I considered cutting a whole in the bottom front of the air box like the one king of the hill dude recommended but I hate to do that and find only minimal/no results. I have looked at a few aftermarket CAI setups and they seem to all put a box back around the airfilter....... doesn't that kind of defy the point? Seems like that's just trading your black factory box for a nice shiny $200 box.

 

yea thats how i feel about those cold airs. suppossedly they benefit alot, but i could never get myself to pay 200-275 for one. i have a aftermarker air cleaner thats like stock but opened up all around it so it can grab more air from the compartment. plan to put a cowl hood on to get some more cold air to the cleaner. it really just depends on the room you have and what else you plan to do you could say.

 

The CAI makes a noticable difference. I had the high flow K+N filter in the stock box, and when I switched to the CAI it was very noticable

 

The cold air helps but isnt nescesary, you need high flow. My intake comes off the turbo and makes a sits in front of the battery, theres no cold air in a diesel engine compartment but I feel a definite power increase because of the difference in restriction.