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Well I put a really detailed post in the high-tech section that nobody replied to. If you want all the details check there. Here is the super-short version:

Changing 1990 EXT Special 530 LC twin from stock airbox to POD filters. Everything else stock, no other engine changes. I am modding and need to make room, so the pod filters are required. So please don't tell me to keep the massive airbox ;) It's too late.

Any guidance on how much to richen the different throttle positions? Do the pod filters actually improve airflow at all with everything else stock and a single exhaust? These are round mikuni carbs VM38. My altitude-adjusted main jet right now is 280, pilot jet is stock 25 (air screw at about 3/4 turn with the airbox), needle is stock: D6H8, stock is position 4 (4th richest out of 5) but I run position 3 at altitude. The needle jet is also stock (listed as Q-0 (480)).

My main concern is I'll need new needles and needle jets. I don't know where to begin with that as far as how many sizes to go up. Can anyone comment? Other than that, what main and pilot jets should I start with? My plan, if nobody tells me different, is to run about a 310 main jet (pure guess), put the stock needle at the richest setting, put the air screw at about 1/4 turn with the stock pilot jet and then start the testing and tuning procedures.

Does this sound safe to start with or am I too far off, and in which direction?
 

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My thoughts are that if you have a good baseline jetting set up you should be able to get away with main jet changes only. Certainly as a start main jet changes should get you running to where you can do a new baseline set up. Two, or three sizes would seem to be a reasonable jump and allow you to work your way back down.
 

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I would start with 10 points up on the main, you will probally need to go with a richer needle jet to richen up the mid range.
jets are a lot cheaper then pistons start real rich and work your way back.
 
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