Jetting Question (with pipes)

[dnale]

THe Max Perf. sheet with my PSI pipes has a page with the changes I need to do for the twin pipes.

I don't understand what they mean here

"JETTING SPECIFICATIONS: 0-35 Degrees F (Jet each side 2.5# each side below 0) minimum 92 octane fuel required with twin pipes

MAIN JETS - 152.5 (PTO) 153.8 (MAG)
FUEL SCREW - 1 1/2 Turns

All other jetting remains stock."

I know I have to run premium fuel. I can handle the main jets. Is the fuel screw they are refering to the pilot screw? If so, stock is 2 turns and fewer turns is leaner. Do I want to run leaner at idle with pipes?

Also, since there is nothing saying to adjust the needle jets, do I let them alone?

What would be a good benchmark for increase of performance? I never timed anything before. SHould I just go sop?

 

[yammy]

yes ,you wanna turn it in do to the fact you added bigger jets. and i believe there referrin to the needles on the 2.5 thhats a half a clip up.....use the lil plastic washer thats on the needles for a half clip pos. the thing i dont understand is when i put psi pipes on my 600 I never touched the jettig .. they said to leave stock!but i did drop my needles 1 notch....put 5000 miles on er and NEVER had a problem

 

[dnale]

How would I know if the Needle jets need to be moved after I install the pipes and run it?

Will I get bog or someother tell tale sign?