I had my GMPP 1.6 rockers installed. The tech set the lash with the car not running. He said he got it to zero lash and tightened it one full turn. Is this right or do I need to adjust them myself? I want the car to perform at its best so I think you want them as loose a possible without being to loose. Everything is stock except for the rockers and LT4 springs in the engine.

 

1 full turn is the factory specification for most hydraulic lifters, although personally I set them at 1/2 - 2/3 turn as on some rare occasions you can have them pump up a little too much at that setting...depends upon the valving in the lifter, but the oem pieces will be just fine at 1 full turn.

 

I thought anything from 1/2 to 1 turn was ok. I think I did mine about 2/3s because it was mid ground. It would also depend if you have stock 3/8 studs or not too though.

 

They should stay quiet for virtually forever at that preload, but it might run better with less.

 

What would you recommend the minimum be? A safe spot but with the best possible gains. 1/2 turns seems to be the least I have seen.

 

1/2 turn should be fine for a stock lifter.

 

Agreed. Comp cams recommend 1/2 turn preload on my Pro-mags as well. I used it per many recommendations on this site and have had no problems with it.