I figured I'd put this up for prosperity....
In the search for a simple fueling solution for my new motor I decided to purchase a second set of stock 440cc 'yellow top' side feeds and try to de-cap them to unshroud the pintle & increase their flow....Reportedly rumored to flow 650cc in unshrouded form.
I started with this:
Note: 4 small atomization holes and their 'D' shape and also the fine robot weld that retains the cap to the tip of the injector, preventing easy de-capping of this type of injector.
Tools: You'll need a Dremel, a soft jaw vice & a steady hand!
I used a fine grinding bit similar to this:
A low speed is best, going slow will prevent removing too much material too quickly.
After removing the plastic atomiser cap, I mounted an injector into my bench vice to hold it steady.
The aim is to grind the weld just deep enough until the centre of the welded cap is loose...
Do NOT grind over the holes themselves or you may go too deep, destroying the pintle tip and ruining the injector permanently.
Take-Your-Time!
If you are careful & take your time you'll end up with a de-capped injector with an undamaged pintle (valve tip).
Cap removed:
Note: the margin around the centre pintle that has not been touched by the grinding wheel.
It is a simple job, but be careful not to touch the centre are of the injector tip at all.
The injectors will definitely require utrasonic cleaning before use due to the fine metal dust created by the grinding wheel.
Comparison of the injectors:
L-R: Prior to removing plastic atomiser - Atomiser removed (shows welded cap) - Cap removed!
Voila! Job Done.
Note: New filter baskets, O-rings & Plastic tip caps will be fitted prior to installation.
I'll post back the results of the flow testing & spray pattern (should be a single cone spray pattern by all accounts).