my radiator cracked on my 91 rs 5.0 tbi, pulled a radiator out of a 87 camaro same size but one problem there is a hose that connects the radiator to vaccum line on my original radiator and this radiator doesnt have a port for that hose. Is there any way to bypass that connection.

 

There is no vacuum line from the radiator, so not sure what you're describing - can you get us a pic?

 

it is directly under radiator cap goes into a 3 way fitting with a vacum line on top it sits behind alternator. It looks like it might be for heater core

 

That's the heater diverter valve - the vacuum line comes from the heater controls and opens the valve when WARM is selected thus allowing the warm coolant to run through the heater core. But the heater diverter valve is not a part of the radiator, it can be located anywhere that you want to run heater hose and that vacuum line to (and can even be removed if you like), so I'm still confused as to what the problem is exactly.

 

Well, that's the heater return line to the radiator in later models, but did earlier ones return to somewhere near the water pump? I know there was an extra tap around there somewhere. If that is the case then maybe those years didn't need the one on the radiator ?

 

i was hoping there might be some type of adaptor either off the lower hose or on the cap that i could get, but i guess i will have to buy the correct radiator. should have payed more attention when i took out the 87 radiator. It the same size all other connections same just missing that return port.

 

But it provided a valuable learning experience. Think how carefully you'll check out the next part you have to replace. We've all done the same kind of thing a million times. Practice makes you a little better?

 

The heater line to the radiator took the place of the earlier design that went to the top of the waterpump. In some cases the waterpump has the port but it's blocked with a plug. Replace the plug with a nipple and you're in business.

However, you don't want a used radiator. The stock composite (plastic/aluminum) radiators have issues with the plastic tanks taking the heat over the years. Eventually they start to develop stress cracks which turn into leaks. All of these cars are old, and any old radiator is going to be susceptible to the same problem. Unless you want to swap in a junkyard radiator every couple months, just spend the $100 and get a stock style replacement.