Also, if your timing is at 14 degrees, that's bad, there is no reason unless you're boosting on pump gas that you should have to back your timing up that much. I was running just shy of 13:1 compression with 15 degrees of timing in humid/hot south florida weather, and it still rarely pinged, even under a lot of load.

Fuel pump really doesn't require any sort of modification, they're basically plug and play. As far as injectors, as Trey said, yours are fine. Also, you mentioned that your computer was a GS-r computer...what type of intake manifold do you have, and if it is a GS-r, perhaps the manifold butterflys are stuck...not likely, but possible. Also, I'm assuming that you got the injectors used or with the motor, did you ever get them cleaned and balanced????

I'd start with the timing, try putting it back to stock, which is 16 degrees. If anything on a relatively stock motor, you want to advance the timing, not retard it...Work from there...

Later,
Aj