You see my setup in my sig. I am darn near at sea level in a southern climate. So take that into account.
After all the other work I did, I noticed a flat spot in my power band at around 4500rpm. Not a loss, just not as linear. Switched to TBS needles and that went away. Have not shimmed because I do not see the need, for me. If you do not have this issue, there is no need to change!!
The only thing drilling the slide's vacuum port with a 7/16 drill bit will get you is a crisper throttle response and that's a good thing. This would help everyone, IMO.
I believe it was Dinqua who tried Thruxton needles and found them to be too rich. I do not remember if this was before or after his BB.
