Well I have my 4.10s, chin spoiler on the way, shifter next month. After that I am unsure but here is my list but not in any order...
Pulleys - I have heard of problems at idle
CAI - I heard that 4.6 run better when cool
Timing adjuster - do you have to run premium gas
Throttle Body - any real gains on a stock motor?
Subframe connectors
Pinion snubber - DO these help you launch
I can't afford the PI heads and intake for some time yet, so no need to mention it.

Pulleys - I have heard of problems at idle
CAI - I heard that 4.6 run better when cool
Timing adjuster - do you have to run premium gas
Throttle Body - any real gains on a stock motor?
Subframe connectors
Pinion snubber - DO these help you launch
I can't afford the PI heads and intake for some time yet, so no need to mention it.

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