That's what I was intending to do, I think HDDP must have misunderstood and thought I was going to use the new small tank for the I/C-HE system.

Originally Posted by Steve Hellums Since I'm just going to use it as an overflow for the radiator I wasn't real concerned about the inlet/outlet size, the volume is the only thing I'm conserened about. I think it has 1/2" though, I'm probably going to tap into the bottom of it for the radiator make up hose so I can make it bigger if I need to. I was measuring the hose's and they appear to be 1/2" ID, the tube's coming from the I/C are only 1/2" and all the hose's look the same size.

I've been out checking out the OEM overflow tank, trying to figure out how it is configered inside. I took a peice of bailing wire, bent a 90 about 2" long on the end and stuck it down the fill hole try to feel how the thing is sectioned off. I found that from the fill hole section there seemed to be a oval or rectangle hole 3/4" high & 1/4" to 1/2" wide to the section toward the front of the car and no access to the section toward the fender side. If you look straight down at the OEM tank considering the way the top is shaped, I think the OEM tank is divided into 6 sections, how the rest of the 5 sections are connected together . So I guess using the OEM tank to circulate the coolant from the I/C HE thru it for more volume may not work.