I have a 90 gta engine in my IROC.......

question ...If I go with true roller rockers...do need to use valve guides?

Seems when I was putting the engine together I tried some but they did not seem to stay on top of the springs...would slide to one side or the other.

Or did I have the wrong ones...can't remember what brand they were now, was awhile ago

 

You sound very confused
Valve guides are the things in the head that valves run
Only touched when head rebuilt.

Are you talking about GUIDE PLATES???
They fit under the rocker studs and align the pushrods
You only need guide plates if you are installing non self aligning rockers ( of any type )

 

guide plates is what I meant...thx

 

Are you fitting self aligning or non self aligning roller rockers?

If you use the self aligning type on your '89 engine you don't need guide plates.
Conversely if you are fitting NSA rockers you need the guide plates and new hardened pushrod to suit