Rebuilding my WC setup

[Lord_RTKK]

I am planning on rebuilding my WC setup.
Now I have a cheap setup, a Hydor L20, a home-made CPU block made by me, a similar block in the VGA and a Civic radiator with 2x Vantec Tornados...
Now I am planning to mounting something similar to this:
First loop:
--> L20,
--> Maze4 for the VGA
--> home-made NF4 waterblock.
--> radiator from a Seat Ibiza. 2x120mm and 1/2" fittings.
The radiator looks nice, and I hope that it could handle the VGA and chipset passively. If it coudnt, I will add a low noise/low rpms fan, and should be enough.
The main loop:
--> DangerDen D4,
--> TDX Brass Top
--> Civic radiator, with the 2x Vantec tornado.

Here are my doubts, I cant find a MCP600 pump, so, is the D4 a good choice?? The TDX is from a second hand forum, a great price (35 €), so I cant go for a G4, and the rad is a great performer, so I will keep it. My main doubt is about the pump, the D4 will do the job fine??
Another doubt is about the tubing. Now I have ClearFlex 3/8" ID, and all the blocks are 1/2", can I keep this tubing or it worths to change it to 1/2" ID?? The temps will be much better??
Hope you could answer all my doubts... ;);)

[BRiT]

Go for the 50Z pump if you're not wanting to run the D5/655. As far as tubing goes, you'll need to get a new set, the tubing won't stretch that much. Pickup either 7/16" or 1/2" ID tubing.

[SustaiN]

You can get the aquaextreme 50Z/swiftech mcp600 at cooltechnica.com. Otherwise I would go for the danger den d5. Don't get the d4 it makes too much noise IMO. I have the d5 and I have only been satisfied so far. It performs very well, makes IMO no noticable noise and has a variable speed knob. But I have some concerns. I assume that the civic rad is pretty big (?) and the TDX is also a very restrictive block so I think u should get better pump like some of the Iwaki pumps. The tdx need a big pump to perform well!

As brit says, replace all your tubing with 1/2" ID clearflex/tygon tube. You'll get better performance...

[JasonDTM]

I've read that Tygon and Clearflex, with some effort will slip onto the next biggest barb, and keeping the 3/8" ID tubing would yeild some hella flow rates as the internal flow channel of the barbs are 3/8" (Going by what weapon said in his classified ad)

[Lord_RTKK]

Thanks for all of your replies... ;)
@BRiT: I only can get a D4 here in Spain without ordering it to foreign countries... :(:( Because of this I am thinking in it... The tubing fits perfectly with those barbs, only a little effort and boiling water :D:D My question is if the performance will be affected if I keep the 3/8" ID tubing... ;)

@SustaiN: I am from Spain, and in the stores of here, I cant find the 50Z/MCP600 pump... :( The Civic rad isnt as big as you suppose. It has space for two Vantec Tornado 92mm or one 120mm fan, is similar in construction to a BIX II or Thermochill 120.2, more or less... sufficient for a single CPU loop, but if I pick up an Iwaki pump, it could be that the rad could not dissipate those extra watts, and have worse performance than with a little pump with less watts... ;)

@JasonDTM: ClearFlex will fit well onto the next biggest barb, the only question that I have is that the performance will be much better with 1/2" than with 3/8" or only will be a 0.5º C differential...