1990 L98 engine heads question

[jjudy]

I sent my L98 1990 aluminum heads to shop for valve and machining work. When they came back my markings for left/right were no longer visible. Looking at them they appear to be symmetrical, same water/oil/bolt/valve/... locations. Are the heads the same and can be used on left or right side on block?

 

[redvett]

All Gm heads fit RH side or LH of the block.

I sent my L98 1990 aluminum heads to shop for valve and machining work. When they came back my markings for left/right were no longer visible. Looking at them they appear to be symmetrical, same water/oil/bolt/valve/... locations. Are the heads the same and can be used on left or right side on block?

 

[vetteoz]

Are the heads the same and can be used on left or right side on block?

But check if you have a plug blocking one threaded hole between the spark plugs
If you do ,you want that one the drv side as the empty hole is for the temp gauge sender on pass side as shown below
PITA to get the plug out later it you swap heads to wrong side

 

[DaveP85C4]

All Gm heads fit RH side or LH of the block.

Is this also true for DOHC heads like Northstar and LT5 ?

 

[redvett]

Is this also true for DOHC heads like Northstar and LT5 ?

Yes on the LT5 but i am not sure on the Northstar but knowing GM i would say yes.

 

[DaveP85C4]

This was kind of a trick question. I assumed you would know that the DOHC heads are indeed NOT the same left and right because the cam drive end is on the front of the engine, and the two ends of the head are configured differently because of the cam drive requirements.

Look at this pic. Pretty obvious that the Left and Right are different, and NOT interchangeable. Northstar is very similar.