Basically just wondering what the massive brain trust of this forum thinks🤷🏻*♂️ I’ve read a lot of older post and done some research and just thought I’d ask anyone with experience in both sizes with a car similar to my current set up.

’06 ZO6
factory 19’s in back
not a daily drive
used mostly for fun on nice days
🚦action and some 50/60 rolls(still getting better at driving) and with the GY F1 3rd gear rolls is all I got till new tires are on anyway
SPECS
kooks headers/no cats/factory exhaust with mod
comp cam(115lsa)
P1-SC-1 6rib and a massive 4.10 pulley(for now)
kenny bell BP/ZR1 MAP
larger injectors(not 100% sure what lb we went with but I can find out easily)
Full tune as well, very moderate for now(4.5-5.5PSI)

lookimg like I’m gonna go with the AHR package as well, that’s going down in June
milage is 14k and the miles on all of the motor work is 3k

sorry this is long🤦🏻*♂️
Power numbers are still a bit of the unknown at the time. I do have the dyno sheet from the previous owner.
Mustang 637rwhp/564Tq

now for the unknown....the dyno pulls where from 2011 when the build was done, to my knowledge nothing changed after the original dyno

but the tune tune was terrible, factory MAP, tiny fast injectors, plugs also not up to par, they also where trying to run an 8:10 duel, they turned off knock all the Knock sensors too🤦🏻*♂️ So we fixed all that BS, car is running strong after first initial tune(dyno pulls and track will not happen till after head fix.

So with all that lol......should I go 345 or 325. Going with NTO5r .

Any thoughts or opinions is greatly appreciated!