valve setting SS

[nhradave]

After great debate on valve setting with fellow racers, this is the conclusion. Super Stock SB Chev.
When the intake opens and is half way to close, set the exhaust. When the exhaust starts to open (50%) set the intake.
This appears to be the best way????
If the valves are set at 22 thou. I am told the 30 thou. is faster but harder on parts (does this not remove lift from the cam)?

[randy wilson]

Yes, it removes lift from the cam And, all cams are different. Some react well from card settings, some like a little looser, some tighter. I had one 292 that loved the intake .05 tighter, to the tune of a tenth. Not kidding, but does not help all engines, or cams. Just try different settings and see. Hope this helps.

[1320racer]

EO/IC...when the exhaust valve just starts to open, you adjust the intake valve lash on that cylinder. When the intake valve has fully opened and is almost closed, you adjust the exhaust lash on that cylinder and you check your settings using the go/no-go method. If your setting .020 lash then .019 goes and .021 no goes.

As for lash adjustments outside of spec...you can safely go .008 either side of spec. Lash loops...opening/closing lash is worth power/ET. Looser maybe be harder on the valvetrain depending on the cam profile.

http://www.harveycrane.com/lashloop.htm

[buzzinhalfdozen]

The very best way to set your valves is to turn the engine using a rachet by hand... turn it in very small increments near the Exh. opening measuring the lash as you move the engine. You will see a point where you measure the MAX. lash, remember this point (maybe jot down the degree off the balancer and what the lash is) when you move it further in the rotation your lash will decrease. The point at which you measure your MAX lash is where you want to check it, as stated earlier some cam profiles are unique and require a different approach. When you have the Int. point of movement figured out, simply use the same method on the Exh. of course at the point the valve has pasted max lift and is closing. I've spent a fair amount of time trying to show my son how to properly (at least in my mind) set valves...he's starting to get the idea of the importance of selecting the proper time to check the lash.

[Mike Pearson]

Depending on your cam selection and rocker arm arrangement your car will probably want a looser valve setting. Mine likes .035 on the intake and .028 on the exhaust. You need to run a good high pressure lubricated lifter to make them live. The lifters are the weak link. I check mine every race and if anything is loose the lifters need to be checked. Use a good quality oil and let the engine run at idle for a while before you rev it up. this proceedure has helped with extending my lifter life. Weak valve springs will kill your lifters as well.

[nhradave]

Thanks for the input guys. This Super Stock stuff is tough, I have bracket raced forever but this is a real brain pain.
My first NHRA event is New England Dragway July, 20 and we are trying to get the set up. The folks at the track have been great, we go for chassis certification on Friday of the event.

Dave Garland
#1000
SS/HA

[Alex Denysenko]

in my ss 289 i have found power on the dyno and et at the track by ruuning the lash as much as .015 looser than spec we've been doing it for years we use only ultra premium lifters and push rods as well as springs retainers etc as this practice can be hard on parts