Hey, I'm putting a EJ20 in my 2000 impreza. I've seen this "thing" in a few engine bay shots and dont really know what it is and if I need one.... help me out.
thanks for the help

 

yes you need one...that is the radiator cap.

 

turbo coolant reservoir

 

radiator cap??? my radiator cap is on, well, my radiator..... since I'm putting that Ej20 in there and using a VF39 I'll need one then to run coolant lines to my turbo right?

 

That is the coolant tank and cap. The reason it is there is to promote coolant circulation after hot engine shutdown, that's why it is located above the turbo. Because of this setup you don't need a turbo timer on these engines.
On the earlier WRX's (02-03) this was the only cap on the system. On later ones (04-up, not sure exactly when the change was made, might have been sometime in MY03), a second cap was added on the radiator. This was done to correct the problem of air becoming trapped in the cooling system when draining/refilling. Since you're doing a swap try and find the later type radiator w/cap, it will make servicing the cooling system much easier. I've upgraded my 02 to the newer radiator and have had zero trapped air problems.

 

right on! so where do you suppose i can find one of those coolant tanks....???

 

good info

 

well I got one of these tanks. does anyone have a diagram that shows where the 4 lines go on the tank? that would be really helpfull.

I'm assuming 1 line comes from the radiator, 2 go to the turbo, and the last ???

thanks again.

 

the last goes to the overflow

 

overflow....cool. now all i need is to know which line goes where. if anyone has a diagram or something of that that would be awesome! thanks again for all the help.

 

so can anyone tell me what lines 1 2 3 and 4 go to? i dont know which one goes where still...

i was thinking, 1 goes to overflow, 2 radiator, then 3 and 4 turbo feed and drain. ( dont know what order...)
please help! thanks again guys!