I got the radiator lines already in but I won't be using my heater for quite some time am going to skip it. What are the three small outlets for? I think the bottom two on the drivers and passenger are heater, but what is the one on the top side of the Passenger? Thanks.

 

On the passenger side, the top is the heater outlet and the bottom is the heater inlet.
The tube on the drivers side of the pump the one that sticks out of the front and is kind of pointed down is for the optional oil cooler, wich also requires a LT1 radiator with an outlet on the bottom drivers side to hook into. If you are not running this option it can be capped off.

 

I was wondering this same question a while ago. Would it be possible to use a third gen radiator and the factory port for the heater return? This way there would only be one heater hose on the water pump.

 

That is intersesting could be a possibility, as long is it doens't effect the pressure and air bleeding capability. Wonder if anyone has routed there system that way?

 

I'm using a replacement 3rd gen radiator and using the heater valve. However I am using both ports on the pump. I don't see why you couldn't use just the one, as long as you had a way to vent the lines if need be.

 

Hmmm, was the oil cooler water pump outlet only on certain years or packages? I've seen other lt1 water pumps and never seen the extra outlet for the oil cooler.

 

It was an option and not all cars had it. Not sure what years or critera are assocated with it. I heard it was part of the heavy duty cooling package upgrade. Probably used on police cars. From what I have read the oil cooler was phazed out with the LS1's due to the synthetic oil helping the engine run cooler.
The LT-1 I bought for my swap came with the extra hookup and oil cooler but I took it off and replaced it with the cleaner looking Corvette water pump.

 

Cool, nice to know I got a little UNF in this lt1 I bought. Ah well, i'll check out that lt1 water pump you spoke about, I might look into getting a oil cooler.

 

Could you use the 3rd gen oil cooler and hook it to the LT1 Water pump oil cooler outlet?..


TEX...how did you route your heater lines

 

I don't see why you couldn't use it, although I've never seen one so I'm not sure how it hooks up.

f-crazy, I'll have some photos of the heater lines coming sometime next week.

 

how did you hook the heater valve up? Did you bypass the TB?

 

f-crazy:

This is how I routed my heater lines.

The top one is a cut-down 4' long Gates brand hose with a 90 bend at the end (seen beside the TB)..like a hockey stick.

The lower hose still uses my car's original hard line above the passenger frame rail, then goes to rubber and curves to go to the waterpump (seen under the radiator puke line).

I capped off the drivers side outlet on the WP and the one on the 3rd gen radiator. The WP is from an F-body.