Valve Shim Calculator

[IndyMX]

I just put together a simple windows program to calculate valve shims..


http://www.quickinet.net/vsc/publish.htm

For those that don't feel like doing the math.. It's probably not perfect, but it will get you pretty close.

I do not take responsibility for you not inputting the numbers correctly or being a complete moron in general. It's just a helpful tool.

Tell me what you think..

 

[_JOE_]

I've heard the actual thickness of aftermarket shims is less than precise. Several guys have used a similar appliction to select shims and ended up with clearances that weren't where they should be. With the aid of a micrometer it's been found some shims aren't exactly the right thickness. I remove the old ones, bag 'em up, mark the bags with the position and measurement, then take them to the local shop and we measure with a micrometer to select replacement shims. Last time I did one we found a replacement shim that was a thousandth under what it was marked.

For folks who don't have the option of driving to the shop to get 'em, the calculator will give you theoretically correct shim. Whether or not the sweat shop worker in China made that shim to exact tolerances seems to be a crap-shoot any more, but hey, what choice do we have?

 

[IndyMX]

I've heard the actual thickness of aftermarket shims is less than precise. Several guys have used a similar appliction to select shims and ended up with clearances that weren't where they should be. With the aid of a micrometer it's been found some shims aren't exactly the right thickness. I remove the old ones, bag 'em up, mark the bags with the position and measurement, then take them to the local shop and we measure with a micrometer to select replacement shims. Last time I did one we found a replacement shim that was a thousandth under what it was marked.

For folks who don't have the option of driving to the shop to get 'em, the calculator will give you theoretically correct shim. Whether or not the sweat shop worker in China made that shim to exact tolerances seems to be a crap-shoot any more, but hey, what choice do we have?

100% Agreement..

This tool should never replace measuring the shims properly, but will help those that don't trust themselves doing the math once they have the measurements.

I would never recommend that you take the shim sizes printed on the shim for granted.

 

[oscaman]

whatever you do, don't loose track of which shim came out of which valve, so at least you can get back to square one if all else fails. Otherwise you have a REAL problem on your hands !!

 

[IndyMX]

Yeah, that can be a problem...

Which is why you should measure them with a micrometer when you take them out..

If they are the same, it won't matter which one they came out of.

 

[Rich Rohrich]

The shim kits made by Hot Cams have proven to be very accurate. That said, anyone who is attempting to do this type of work without a good quality micrometer to measure the shims should have their head examined. One last thing, unless you are a machinist with lots of experience using them, dial calipers are NOT a substitute for a micrometer.

 

[Rooster]

Thanks, Rich. I was just making a Christmas wish list, I will add the micrometer!