Ok, heres teh thing. My radiator took a crap so i need to replace it. My friend has one from a 1985 Z28 that he let me have. I put them up to each other and I noticed that my rad, from a 1988 GTA 350 had an extra hole. The hole is up by where the cap is. I don't know why mine has that whole and his doesn't. ANy answers.
Jason

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1988 Pontiac Trans Am GTA
350 tpi, Fully Stock
BEST ET 15.4

Stereo
Alpine CDA-7864
Power Acoustik Apache Series 2200 watt amp
Two MTX Thunder 8000's in Thirdgen Box

 

it's the return hose for your heater.

just hook it somewhere else like back on the intake.

 

What do you mean???, how do i do that
just cut into the hose or by pass the radiator..., It is a small hose, not a big one
Jason

------------------
1988 Pontiac Trans Am GTA
350 tpi, Fully Stock
BEST ET 15.4

Stereo
Alpine CDA-7864
Power Acoustik Apache Series 2200 watt amp
Two MTX Thunder 8000's in Thirdgen Box

 

as long as it ciculates back into your cooling system, then it doesn't matter how you do it.

 

It might be for a low coolent level sensor. Just plug it.

 

ODB is right, thats your heater return hose. The easiest place to plumb it back into your system is the same place it was on the 85. On the water pump, on top of it you should see a pipe plug. You need to remove that and put in the appropriate sized nipple for your heater hose. You can get the nipple, prolly at any hardware store, definitely in any automotive store, usually with the HELP! stuff.
...ed