So I checked my valve lash

[Stretch]

I checked the lash on my valves today, and found my intake side to be running a pretty tight ship. What sort of problems could arise from leaving the clearances so tight? I have many with only 5 thousanths clearance, where the minimun is recomended to be 6, so I wanted to know what if any problems running it at 5 like it is would cause me. Btw, stock cams, stock head.
eric

 

[Nick M]

In theory, the valve wont seal. But you arent way outside the boundries either. When the valve heats up, it will expand. Just like everything. The lash is there to take up that expansion. When you are too loose, besides being noisy, the valve wont open as far as it is supposed to.

 

[IJ.]

If it were really tight you'd run the risk of hanging a valve open during the power stroke and torching the edge off and this as you can imagine is a bad thing!

 

[Supracentral]

Aside from potentially burning up the valves (and the possible detonation issues when you have something in the combustion chamber that is glowing hot), the other issue would be excessive cam wear. One thousandth too tight is likely ok, but if you have some thinner shims, it can't hurt to back them off, but you likely don't have to.

I'm psychotic when it comes to tolerances, so I'd probably reshim the head, but that's me, and I'm pretty goofy when it comes to this stuff... :aigo:

 

[Stretch]

Alright, thanks for the words guys, I wanted to hear what a bunch of the intelligent supra owners had to say, you guy were the best I could have asked for. I'll check my shims, I do have a whole other head that's garbage I can salvage for shims, so we'll see if I can increase some of those gaps back within spec a bit.
eric

 

[Nick M]

Those shims retail something like $10.00 each.

 

[Stretch]

So are you saying you want to buy my extras then Nick? :icon_razz
eric

 

[IJ.]

Alright, thanks for the words guys, I wanted to hear what a bunch of the intelligent supra owners had to say, you guy were the best I could have asked for. I'll check my shims, I do have a whole other head that's garbage I can salvage for shims, so we'll see if I can increase some of those gaps back within spec a bit.
eric

DOH and you got us !

 

[Nick M]

If I had extras, I would be pleased.

 

[billspreston01]

the question is...did you measure it when the engine was still warm? It's supposed to be 100% cold when you measure. If it was warm then you'd probably be within spec when it's cold

 

[Stretch]

Yeah, I measured when the engine was dead cold. I haven't fire this engine ever yet, so it's pretty cold :icon_razz
eric

 

[billspreston01]

well that takes care of that problem. I don't think you'll have a problem with such a small difference. Mine are way out of spec...but the gaps are too large so my problem is different.

Speaking of which...anybody got any spare valve shims (all the larger sizes) cuz I should fix mine