I know the manual says to let the car sit overnight to let it cool completely but really how important is this step?

I drove it a little this morning, you think it'll be alright if I go ahead with the install 8 hrs later?

 

You'll be more than fine, i drove mine 30 min to a shop and installed it right when i got there.

 

You don't have to, but if you can, do it.

 

the reason i believe they tell you that is because like all metals it expands when hot wand contracts when cold so if you do it when it is hot you might have to go back and retighten the bolts so there is not leaks, or so you dont strip the theads when it is hot due to the metal will be more soft the hard while heated up

 

Its best to do it cold because of the different thermal expansion coefficents of steel bolts and the aluminum plenum.

Aluminum expands more than steel when the temperature is raised. And when the plenum is hot, the bolts are under more tension than when it is cold.
When you try to unscrew bolts from a hot plenum they can snap simply when you try to unscrew them.

I know, I've done it.

 

Didn't want to start a new thread, but I just installed my 1/2" iso thermal spacer. Is it absolutely necessary to install the valve on the coolant hose? It was dark outside by the time I finished and I have work tomorrow morning. I just want to know if it is okay to drive around for a day without installing it or is it totally optional? Thanks. Love the spacer btw!

 

I waited a few hours after driving... and I just went back and retightened the bolts after ~150 miles and then letting the engine cool overnight

 

yea 8 hours is perfect


this step is VERY important, the lightweight aluminum expands and contracts CONSIDERABLY... the instructions have specified torque that would allow expansion once the engine is running. if you torque to 100 inch lbs on a hot engine, the plenum will come loose when the engine cools down!!!

 

^ GUYS I brought this thread back from the dead. I have a new question(post#6). Stop answering the OP's question LOL.

edit: got your PM UR2EZ. My question is answered. Thanks!

 

No, its not necessary to install the valve, but it is better if you do. Install it when you have time.

Tony