Upgrading an ICS M16a3
 

I'm planning of buying a ICS M16A3 and making it into a semi auto aeg.
with this upgrade kit will it be able to use a sp120m/s aeg spring ?
Or what would be the strongest spring you can use without the gearbox breaking.
Will the stock gears break with that kind of spring ?

The upgrade:
special upper gear box type F with m120

upper gear box kit with metal spring guide,long barrel bore up cilinder full set,metal piston and m120 spring for all m4 ics

you still need to put metal bushings into the lower mechbox.

what's the diameter of the bushings ?

I'v been running that MA-56 (type-F) for a few Months with great success and and the stock gears will hold up to the task if your running metal bushings and a good shim job.You might need a better motor,depends on what you have now.I found I needed a high-torque motor and I'm running a 9.6 1700mAh battery.I found that it's a little harder on the battery in terms of how many shots you'll get out of a charge.As for the bushings just buy the ICS ones as they drop right in,ICS uses an odd size,it's just a hair under 6mm.

I suggest you wait a few weeks for the retailers to get the new verion in stock.

It has steel bushings, a turbo 3000 motor, and a strengthened gearbox.

http://www.icsbb.com/news/e_news_main.asp?id=85

what is the version of the parts in the upper gearbox ? v2 ?

V2
But there have been some reports of certain parts not being as-compatable as they should be... couldn't tell you exacly which though, other than tappet.