Z9 A4 restored....help please

[DonB]

I’ve put a 4into1 exhaust and running k and n air filters, do I need the air corrector jet kit and what size should the main jet be?

[zed1015]

Ideally you do want an air corrector kit to fix the off idle fuel gap and then go up on the mains.
With the corrector kit you don't need to go as big on the mains as you would without.
On average you want to be around 117.5 mains but it depends what carbs you are running and other factors.
Start with 120's and work down.

[DonB]

Thanks ever so much, most helpful