Freeze plug in a LS water pump

[85toyo]

I'm trying to find the correct size freeze plug to go in my 2001 LQ4 water pump. After searching around at Advance Auto and Napa, I found a steel 32mm that seems like it will work. From what I can see the rounded edge barely sits down inside the hole. The only other size I could find that was close was a 1 1/4 and it's just small enough to slide through. I've never messed with a freeze plug before so I am trying to make sure its not going to crack my pump. Does anyone know if this is the right size? Should I use a brass plug instead of steel to reduce the chance of cracking the pump?

 

[jmh78]

31 mm with a 1/4" hole drilled in it. You only need to do this if you are deleting the thermostat and running a speed density tune.

 

[85toyo]

31 mm with a 1/4" hole drilled in it. You only need to do this if you are deleting the thermostat and running a speed density tune.

How does that have anything to do with a speed density tune? I thought a density tune was for deleting the MAF sensor ???

 

[jmh78]

Speed density tune is kind of dumbing the system down from my understanding and pretty much putting it in closed loop all the time. Your temperature normally is what would tell the system it is time to go to closed loop. If your are not running that tune and you have the thermostat deleted then you probably will not get it hot enough to go into closed loop operation.

 

[crawler nut]

So I have a Jims Performance tune. All I know is, it is the 93 octane premium tune from him. Do I need to take out my thermostat an go with the freeze plug? Or stick with a thermostat? Thanks for the help.

 

[85toyo]

Speed density tune is kind of dumbing the system down from my understanding and pretty much putting it in closed loop all the time. Your temperature normally is what would tell the system it is time to go to closed loop. If your are not running that tune and you have the thermostat deleted then you probably will not get it hot enough to go into closed loop operation.

From everything that I have read, engine temps should be 180-210 when using the freeze plug which would be normal operating temps.

 

[jmh78]

Should be good to go then. I talked with Schwanke engines about a harness and they use the thermostat delete along with speed density tune on a harness that does not use O2s or knock sensors. We used one on a friends buggy and it seamed to bounce from running extremely rich to lean alot.