Extra spring notches in MIJ Mustang tailpiece posts?

[Ricey]

I have a KC Mustang. The vibrato action is very loose. I don't think there is enough spring tension to bring the strings back up to pitch after dropping down the bar.. The guitar goes instantly out of tune as soon as I touch the bar. The KC has one of those Fender Tun-O-matic clone bridges. My Classic Player HH Jag has that same bridge and scale length and it stays in tune better than any non-locking trem unit that I have ever played, so I am thinking the KC can be set up to stay in tune much better that it does currently. The trem action is much stiffer on my Jag, so I think that may be part of the solution, as well as possibly a shim. The Jag has an angled neck pocket, which also increases string tension somewhat. The tech that works on my guitars said there is an extra set of spring notches cut in my Mustang's tailpiece posts that he does not normally see in a Mustang. Moving the springs to this notch would increase the spring tension, but he said I might have difficulty changing strings because the cigar tube thingy would rotate back such that the string insert holes would rest at an inconvenient angle relative to the body. I am thinking that I could just simply push down on the vibrato bar with one hand and insert the strings in the holes with the other. Has anyone ever seen or utilized these extra notches in a KC or other MIJ Stang? If so, did it make it difficult to change strings?

[Horsefeather]

The Mustang vibrato is a shit design. The extra spring notches will increase the leverage the springs have on the cigar tube posts, which will increase the pressure the posts exert in the vibrato plate, which will increase the wear on the holes the posts pass through and hinge on. When those holes hog out and deform, vibrato action will fall apart again and the only recourse will be replacement or redesign. The only recourse for a shit design is redesign. My preferred solution is to acquire a Jazzmaster vibrato and cut a slot and screw holes in the Mustang vibrato plate to accept its innards, along with some form of roller saddles.

viewtopic.php?f=8&t=94048&hilit=mustang ... d&start=15

[MechaBulletBill]

The Mustang vibrato is a shit design.

No, the MIJ vibratos are made from soft, inferior materials and the springs are too soft. Vintage units work rather well, especially for downward pitch shifts.

Set the springs at the end of the posts, get the tailpiece down as low as you can, allow the bridge to float (or rock) and - assuming everything else is setup correctly (nut) - you should have minimal tuning problems.