Can someone expand upon ported upper intake, and how it relates to the 4.6 02 GT motor application. I am about to install a bbk 75 mm tb and want to cover all the bases, also the plenum situation , I could use some advice, thanks.

 

first off a 75mm throttle body is WAY WAY WAY too big unless you have a super charger with 9 lbs+.... 70mm is the max natrually aspirated, that 75mm throttle body will probably hurt your performance........porting the upper intake (plenum) is just to clean up and open up the intake to allow for better airflow... <edited><editID>Black Horse</editID><editDate>38002.9830787037</editDate></edited>

 

My plan is to go Nitrous or maybe supercharger- I dont want to keep changing TBs.

 

You might wanna think about getting a C&amp;L or a Trick Flow upper intake. If you port the stock intake. It's still not gonna be a true 75mm all the way through.