I just got my custom griffin radiator setup with dual Spal fans
It is made to fit thirdgens as with any replacement but has the hose hook ups as the LT1 radiators - atleast I hope which is what i am checking with you guys lol

There is a hose hook up at the lower right and upper left corners and then one hook up line at the radiator cap fro the over flow. There is a threaded fitting for the drain plug at the lower right corner and then at the upper right corner there is another treaded opening - what is this one for?

I am not running any heat or a/c or trans cooler so how will all the connections work from the water pump to the radiator if I only have two hose fittings?

On the right of the water pump there is a line out to the heater core and a line out to the radiator - do those both go into the upper left connection on the radiator with the special hose that goes two into one? I do have that hose new.

Then what about the passenger side of the water pump - one line goes from the lower right of hte radiator to the passenger side of the water pump and isnt there one other line that needs to go somewhere from the water pump on the passenger side?

 

lt1 and ls1 cars have a coolant tube fitting that would go on the upper right as well.

 

where does that go to? I'll post pics tonight

 

Here are some pics... Can anyone help confirm the way to run the cooling lines? I am confused by the 1994 and 1995 cooling line diagrams as they are both different. THe 94 shows the steam pipe going into the top right opening of the radiator but the 95 shows the steam pipe going into the TB... I have a 1994 LT1 with 95 style cam and opti.

Any help would be appreciated.

 

Here are the two diagrams I was looking at.

 

Here is a little diagram i drew up.... but I hope these pics help you... like i said in the diagram i forget if its a 94 or 95 upper rad hose but whereever you go should have them in stock so just take a look at them, but you will need to purchase another random length peice of 3/8 hose i believe and coupling them together... then it will go behind your water pump and underneith your TB to the coolant rail that is mounted on the passanger side of your intake manifold. A little trick for getting the lower rad hose on is to use a little bit of vaseline because the lower rad hose diameter is a bit smaller than the original 3rd gen hose so it takes a little muscle to get it on. And as for the overflow port i ran a line to an aftermarket coolant overflow container I purchased from jegs. Hope this helps, any other questions lemme know.

 

my wording from the diagram didnt show up really well but the lower rad hose is from a 92 corvette... and the two lines that are indicated in red are for the heater core. As long as your custom rad has the same hose fittings at the 3rd gen rad this setup should work out fine for you.

 

dont mean to hijack, but maybe you can help me out, im doint the lt1 swap and im not sure on the drivers side of the water pump, what is the fitting below the upper hose fitting go too? and also did you use that upper hose to run your steam tube into?

 

I am not running any A/C or heat so I will not have the heater core hooked up... or do I have to have it anyways? Dont see why I would need it. But assuming I dont have it what do I do with those connections then?


On the right picture it looks like there are two hoses going to the radiator one high and one low... it may just be how the pic was taken. But I have a radiator hose that looks just like the one you have where its a larger diameter at the radiator and connects to the water pump and half way through there is an attachment for a smaller diameter hose which in you photo looks like it goes behind the thermostat and some where under the TB.

Still not sure what goes to the fitting at the top right of my radiator - see my pics

 

yea your upper rad hose if its like the one i have in the picture has a connection for a smaller hose, i believe the diameter of that hose is 3/8" and it goes under the throttle body and there is a steal line that mounts to the bolts along the passanger side of your intake manifold where that hose connects to... this may be the "steam line" that was mentioned, but I'm not sure of its technical name. As for the fitting coming off of the water pump right below the upper hose connection I had removed that connection from the water pump and put in a freeze plug.... right now I forget what that fitting was for, but it goes to a part off of a 4th gen LT1 rad, not used for the 3rd gen rad.... its been a while since i did all my research on the rads and the connections so I'm just going off what I remember from the top of my head... this might also help, here is a thread i posted of my LTx swap showing off some pictures, https://www.thirdgen.org/forums/ltx-...-ltx-swap.html , check them out and some of the photos maybe able to help you out. And as for the not using the heater core just do like i did for the connection on the water pump and remove the connections and put freeze plugs in their place. the heater core isnt necessary if your not worried about getting cold haha. But hopefully I was able to clear some stuff up and sorry I dont rememer what that lower connection was used for? I just can't remember lol, but it might come to me. Any other ?'s just lemme know and hopefully I can help.

 

1. Heater Core
2.Upper Rad hose connection
3.this is the connection I forget, but it was eliminated and a freeze plug was put in its place. (you can see the freeze plug in my other photos)
4.This is where the coolant temp. sensor goes
5.Heater Core
And at the top of the water pump is where your neck goes and that connection is for your lower rad hose.

 

The radiator I have is supposed to fit just as a stock 3rd gen replacement but has the fittings of a 4th gen radiator. So technically its a 4th gen radiator...

 

so this looks pretty easy then... I can just plug connections 1, 3, and 5 and be good. What kind of freeze plugs did you use? Are they the same types used for the engine block? How did you get a good seal?

I still need to figure out what the top right hole on my radiator is for... because if I do what I said above all I will have is two hoses to and from the radiator and one hose for the overflow and I am good to go.