Help with upgrading internals

[Pancake]

I just opened up my gearbox for my first time, because my birthday and christmas is coming up and i plan on upgrading it very soon.

I want my Dboys m16 to shoot consistently around 400 FPS, and have a decent RoF.

So my questions are:
1. What brands should i focus on?
2. Do i need high torque gears since i already got a high torque motor and will only be running a m120?
3. What type of cylinder/cylinder head do i need?
4. What wiring should I get and how would i go about upgrading to deans instead of tamiya?
5. My new motor I got is from Matrix which I believe is a Evike owned brand, are their products any good?

Thanks a lot!

[NORDIC]

1. modify, systema, and G & G
2. yes it is advised. make sure the gears are not heap metal. one again systema and modify
3. you need a piston head that seals nicely. i personally i like the polycarbonate heads. if your replacing the head get a polycarbonate piston too. and make sure the head has good barrings.
4. that im not too sure on someone here should know though
5. i haven't heard any bad reviews

[Lushes]

This might help a little.
http://www.airsoftpacific.com/viewtopic.php?t=9547

[league 4]

1. modify, systema, and G & G
2. yes it is advised. make sure the gears are not heap metal. one again systema and modify
3. you need a piston head that seals nicely. i personally i like the polycarbonate heads. if your replacing the head get a polycarbonate piston too. and make sure the head has good barrings.
4. that im not too sure on someone here should know though
5. i haven't heard any bad reviews

Your post was seriously unhelpful.

As for brands, it depends on what part you're getting. Stay away from Systema.

High torque gears aren't needed for anything below an M140. You could even run them with an M140 and be fine if you had a decent motor and high amperage battery.

Cylinder shouldn't need replacing, and as for a cylinder head, I like the guarder double O ring ones personally, but almost any will do fine. I'd only recommend replacing it if it gives a compression leak.

Stock wiring should also be fine unless you're running a high amperage battery. To put deans connectors on, you just cut the tamiya ones off and solder the deans on, it's very easy. If you don't have the tools to do that or don't know how, an RC shop could probably do it for you, or almost any tech in your area.

Matrix doesn't make the motor, it's a rebrand of the 5ku high torque motor. It's a good motor for the price, you just paid a little more than you needed to for the same motor.

I'd also recommend you get a new nozzle with an O ring, and metal bushings if you don't already have them in the gun stock.

[Falcon7]

For an m16 length barrel you should use a non-ported cylinder (no holes). It should come stock that way, but the world is a messed up place and sometimes they don't.