The swap is complete, so when i'm driving the roc around and on the highway my temp hits 220(sometimes higher).

For cooling I'm using the following combo:

3rd gen radiator
305 temp switch
1 Linclon Mark 8 electric fan(must be like 17" or so)
Didn't change the thermostat(using what came with the engine)
Bled the system twice
Havoline 100k mile coolant

My 95 ecm was programmed to have the fan come on at 180 degrees(ecm & wire harness was reprogrammed from howell industries). Even when the LT is at idle I noticed the fan comes on at just above 100 degrees. When the temp is at about 120 -150 the upper hose is pretty hot and the lower one is cool.

Was wondering if anyone else is having the same issue?
It's puzzling me.

any idea what I should be looking for?

thanks

 

Try replacing the thermostat with a lower temp one. Sounds like it may not be functioning properly and since you seem to need one....a lower temp one would be ideal. I have Hypertech 160 and mine never gets past 145 or so with only a single fan working from a dual 3rd gen fan setup. I am also using a 3rd gen radiator that I bought new. Let me know what happens.

 

definitely try a new thermostat. If that doesnt work, before you do anything else take your radiator and get it rodded out. If it is your original radiator you'd be surprised how much crap can build up in those. With a brand new radiator and a 160 thermostat with Hypertech fan switch, my fans are never coming on, the temp stays around 165 all day long.

 

is your coolant really getting dark ?? if so check for blown head gasket.


is the steam line running in the back of the engine plugged correctly ???

do you get alot of pressure inside the rad after driving it for a while ???

Do you still have the wind deflector under the car ???

 

would you know if the 305 thermostat fit the LT1?

 

it will fit but its the wrong one. The LT1 therm. is a 2 stage one, whereas the regular SBC therm is a single, makes a pretty big difference.

 

thanks texaslt1!

 

anytime