can the main jets on twin fortys be drilled out to a bigger size to give more top end power. main jets 115

[Edited on 20/7/06 by ian furness]

yes they can with the right drill size.Lookat dave andrews page via links above

You can only have main jets that deliver the fuel required for the air your flowing, otherwise, at best, you'll run rich.

If you have oversized jets you can fill them with solder and re-drill just in the short term to see where you want to be.