General ???'s for my build

[foxbdy88]

Im gonna be running

Stock refreshend short block
Untouched as of now GT40 heads (plans are to upgrade the springs with the Crane 44308-1 kit and a 3 angle valve job)
Cobra upper and Ported GT40 lower (Matched to a FelPro 1250)
TFS1 cam
24lb injectors
190lph fuel pump
3:73's
Full exhaust


Questions are,

I have a 3/8 phenolic Sound i install this? will it help with anything?

How much of a performance difference will i see from the stock rockers to 1.6RR's to 1.7RR's

 

[parrish5o]

You will mainly disperse heat with the spacer but a small gain in tq. If you have it use it. As far as power, prob high 13s.