I just got done installing a TPIS ZZ-9 Camshaft in my L98 TPI (1988 GTA 5.7L). I have Comp Cams 1.52 Ratio Self-aligning Roller Rockers. With the increased lift on the camshaft, the rocker arm travels so much more that I can't get a socket on the adjusting nut on the rocker arm. I tried to adjust the valve lash while the engine is running but it is impossible. The socket keeps being thrown from the rocker arm. I called TPIS for some advice but they told me to:
Adjusting lifters is the last of the assembly steps. It is also a good place to get messed up. The following procedure works for all 4-stroke engines:

1. Insert all pushrods.

2. Pick any cylinder to start with.

3. Turn motor over until you just see the exhaust pushrod move.

4. Install the intake rocker arm.

5. Install the rocker arm adjusting nut.

6. Tighten nut until all free play is gone. (Be careful not to collapse lifter)

7. Turn motor over until intake pushrod opens all the way and then just close. Now repeat steps 4 through 6 for the exhaust rockers.

8. Do all the other cylinders.

9. Now tighten all adjusting nuts one more turn.


Should I follow this advice? Will i have to do a readjustment after the engine is running or can I stick to this? Thanks.

Joe

 

Do this,pick any cylinder,#1 for starters,do one at a time,turn motor over clockwise until the exhaust rocker moves down,like the valve is opening ,THEN adjust the intake rocker of that cylinder,don try to adjust the exhaust rocker when it has tension on it from the cam.Tighten nut while spinning the pushrod,it spins freely when no tension is applied from the rocker,as soon as you feel the slightest bit of resistence while turning the pushrod while tightening stop,you now have zero lash,now spin the nut 3/4 to 1 more turn,NO MORE.Now continue turning the motor over until you see the intake rocker open,no do the same for the exhaust.Take your time do 1 cylinder at a time.Just assemble the whole valve train loosly and go from there.One at a time,email me for info if you need it.

 

Moving this to the "Tech/General Engine" forum. This forum is for aftermarket parts review.

Thanks for your understanding.