1999 7.4 upgrade /performance questions/suggestions

[taco ed]

I have a 7.4 Vortec w/ just a K&N air filter- throttle body spacer and flow master series 70 mufflers on it- what else can I do to up it's performance? It isnt a real go getting and MPG bites the big winny 9 MPG in town maybe 11-12 on the inerstate .. it has 4 10 gears as well its a 3/4 ton crew cab.. looking for suggestions

 

[GMstrong]

Ditch the thorttle body spacer.Get some longtube headers,and ditch that flowmaster.I would also clean the thorttle body,do a full tune up,Also ditch all the unneeded weight spare,hitch if you dont use it,etc.

 

[EmersonHart13]

It isn't going to get that much better, especially in the mpg department.

If you really want to make it go:

http://www.truckmodcentral.com/forums/showthread.php?t=14795

Put a Whipple on it!

 

[taco ed]

I thought the throttle body spacer helps?