jetting question

[banshee11]

put my new ported cylinders on last night, which are ported dune drag and i have 55 pilot and 165 mains, can i put 52 pilots in it and be safe. with the other cylinders not ported as hard it had 155 mains and 55 pilots it has cpi pipes and 4mm crank with 35mm carbs. thanks

[dajogejr]

No way to say for sure. Sometimes a ported motor pulls more fuel from a smaller jet, sometimes...and more freequently, it requires more fuel.

I would leave the jetting as is. See how it runs.

[banshee11]

with the cylinders the way they were ported the first time at 155 it was a tad lean. and ported harder it is a little less responsive down low and i wondered if a 52 pilot would help it a little. does opening the exhaust ports up bigger require more fuel on top and bottom end which one or more.