when taking off the head do you NEED to change your headgasket? just wondering if its something you MUST do.

 

I would if it was my car, but many people just spray both sides of the gasket with copper spray and put it back in without any problems, its up to you

 

yes. don't be cheap. do it once, do it right.

 

Yes, thats a must. You might as well if your taking the time to remove the head. Plus its a good idea anyway to prevent future problems.

 

is it no longer good once it has been torqued?

 

think of it this way, you remove it, make a few changes and put it back on, and it fits the same. Suppose you had a grilled cheese sandwich, and you pry it apart and remove the cheese (assuming you can do so without the bread). Then when putting the sandwich back together you can either used the cheese already formed to the bread, of a new slice of cheese that will conform to the slices of bread again

 

Wasn't a must on my car. I pulled my head on my B18A to replace a bent rod from a hydro-lock incedent, and re-used the same headgasket with 250K miles on it. No problems so far at 294K.

If I wasn't so poor at the time, I would have swapped it, but sometimes you have to do what you have to do. I am curious if anyone else has ever re-used a headgasket and what the result were.

I have heard that head studs must be replaced also, mine seem to be fine.