[SolidStateS15]

it depends on the engine, but for the most part a spacer is junk. on the 4.7 it is worthless.

there is a thread on here about backflushing the heater core. try that first before you go replacing parts.

superchips 3715 is around 300 and a good investment, although it will be more noticible after some more mods are done first.

 

[SolidStateS15]

http://www.dakota-durango.com/forum/showthread.php?p=1946014#post1946014

lots of claims are false.

the superchips has 3 modes and some selectable options. it's as close to programing as you can get without moving up to an SCT which uses custom maps.

 

[SolidStateS15]

it's been tested and 3" works the best. single 2.5" is pretty small for a V8. you will have a better torque curve and more useable rpm power range with the 3" and 2.5" Y-pipe.