You can get some good gains from a stock SE UIM by honing and polishing the ports using a flex hone. I wore out a 1 1/4" and a 1 3/8" hone on my UIM about a month ago and was real happy with the results. With a SVT LIM, you should be able to get even better gains. Check MSC industries for flex hone tools. Search here ->
http://www.mscind.com/ 
