Upgrades to increase FPS on GBBs

[CanIplayDaddy]

Hi, just want to know,

besides adding a hi flow valve, metal slide and barrel and using TOP gas or higher, what are the other ways to increase FPS of a GBB, say a TM G26?

Btw by adding all the above upgrades to a stock TM G26, what will the FPS of the Glock be? I think the FPS of the stock Glock is about 260-280 FPS?

Can upgraded TM GBBs take red gas?

BTW I just want to use it for target practice, not using it for skirmish.

[Grim Fandango]

don't forget to get a stronger recoil and hammer spring. I wouldn't use red gas in it, stick with propane.

[Mantelope]

If you're spending a buttload of money on a G26 anyway, get the Guarder steel slide and barrel. Definitely one of the nicest metal slides I've ever seen.