help upgradeing tm sig 552

Discussion in 'Gun Building, Modifications & Repairs' started by lenoob, Oct 18, 2012.

  1. lenoob

    lenoob New Member

    I'm not sure if this is the right place to put this.. but here goes... This is going to be the first time ill be working on internals... But I'd like to know, what can the stock mechbox take? As in how strong of a spring. And what to upgrade to be able to make this thing shoot at about 380-400fps.
  2. Lefse

    Lefse Well-Known Member Supporting Member

    If it has the usual TM internals, then the internals are fairly weak. I recommend replacing the stock gears, JG gears are dirt cheap and will be a huge improvement over stock. The piston is pretty durable, and will hold up in a moderate setup with corrected AOE. I wouldn't use anything stronger than an M110 spring, tops, with stock internals. Here's what I would do:

    Gears: JG
    Bushings: Element oilless steel
    Piston and piston head: Lonex
    Cylinder head and nozzle: Stock are fine, but for better compression and durability, go with Lonex.
    Spring: M120, I've had good experience with Lonex, but many people prefer SHS, Prometheus is also good.
    Spring guide: Lonex or pretty much any steel ball bearing spring guide will do.
    Motor: Lonex A1 or A2 (A1 is slightly faster), or an Element ultra torque to save a few bucks.

    The stock motor can pull an M120 on standard ratio gears, but will require a strong battery, I recommend a 7,4v li-po. You should consider installing a MOSFET unit and get a good 11,1v li-po, this should put your ROF around 25rps. If you want a new motor, then you can't go wrong with a Lonex motor.
    You'll have to research the internal mods like correcting AOE, shimming, swisscheesing and so on yourself, I won't do you a favor by spoonfeeding you too much.

  3. lenoob

    lenoob New Member

    Thank you. I just needed to know where to start upgrading. So I'm not wasting money. I didn't want to upgrade something I didn't have to and end up wasteing a few bucks.