Gtm Supercharger pulley discussion

kentmo280z

On my original GTM stage 1 supercharger set up I had an 84 mm pulley.
Ran at 405 rwhp w/ 353 lbs torque. The kit came with a funky intake & 2.5 " maf pipes. The car pulled great from low end up through high rpm.
Since then , I upgraded to the stage 1.5 kit. The 92mm pulley that should have been supplied with the kit was not available at the time of purchase, so I ended up buying a Kraftwerks 90mm pulley.
The 1.5 kit intake is 3" , the supplied MAF pipes were not symmetrical in shape and are 2.75".
Reading Sam's original post on the Stage 1.5 kit, the MAF pipes were to be 3".

So, all the items were installed, had the car dyno tuned and the numbers were kind of disappointing . 454 rwhp and 338 torque. Notice that the torque went down 15lbs., which I can feel in the low end driving.
Since having the dyno done, I fabricated 3" symmetrical MAF pipes but have not retuned yet.

This is where I need help. I WANT MORE TORQUE. Is a 88 mm pulley really going to make a difference over the 90 mm which I currently have installed?
If I install my 84 mm pulley , will I be in risk of popping the engine? I could have the tuner adjust the rev limiter to 6.5 or 7k rpm if needed.
Why would a fuel return benefit this setup? I have the fuel pump relay installed and 1000cc injectors installed also.
I see some setups with an 85mm pulley, so is the 84 mm pulley that mush more radical?