Hello frens,

I've got the car apart swapping out the exhintake cam back to the stock intake cam (because I failed to drill the cam gear correctly and don't want to bother with it anymore), and since I'm in there I'm checking the valve lash. Most of the exhaust was ok or close to it (able to get it all in spec by moving shims around except on one lifter), and the intake was way too tight with the stock intake camshaft being used for measurement so I've got to buy all 8 shims (the exhintake cam was used for setting up the valve lash). Right now I've got a big *** excel spreadsheet trying to figure out what exactly I'm wanting to do.

On the intake side, I'm in between sizes since the shims only come in .05mm increments, which is conveniently the same size as the allowable tolerance window (.18mm - .23mm). I pretty much have to go with either .18x mm or .23x mm of valve lash because of this. So should I chose the bottom limit or the upper limit? The proposed intake valve lashes would be as follows:

Shim 8: 0.231mm or 0.183mm
Shim 7: 0.231mm or 0.183mm
Shim 6: 0.212mm
Shim 5: 0.212mm
Shim 4: 0.237mm or 0.189mm
Shim 3: 0.212mm
Shim 2: 0.234mm or 0.186mm
Shim 1: 0.234mm or 0.186mm

I'm personally leaning towards going with the loose option/0.23x mm. My idea is that the stock valve lashes are recommended for stock cars. This one is turbocharged although 95%+ street driven. Furthermore, wouldn't excess lash only cause the valves to not open as far as possible while not enough valve lash could burn up a valve? Is there any reason to not go with the loose route? The tiny drop in power from valves not opening an extra 0.05mm can easily be offset with more boost.

Lastly just since I'm already here, for the exhaust side the lashes will be as follows (using 0.28 mm - 0.34 mm):
Shim 8: 0.303 mm
Shim 7: 0.316 mm
Shim 6: 0.305 mm
Shim 5: 0.294 mm
Shim 4: 0.326 mm
Shim 3: 0.305 mm
Shim 2: 0.319 mm
Shim 1: 0.326 mm

Does this check out? Hoping to buy the new shims tomorrow, but since I can't find shims for less than $16 each I figured I'd look for a second opinion (or more). Also, if you all know of anywhere cheaper in the US I'd love to be informed. I'm currently using trackprepperformance.com. Thanks

 

https://www.precisionshims.com.au/products/flat - provided in 0.02mm increments. Most likely more expensive to your door with shipping and tax etc.

If you have had a valve job then I would err on the looser side as the valve job will most likely bed in a little depending on tooling used, chatter etc. when cutting. This bedding in may decrease your set clearances slightly.

 

Worth a question, exchange rate is in your favour, and freight should be three fifths of stuff all.

 

Unfortunately I went ahead and ordered them the other day (the 0.23x mm route). Also this engine has ~10k miles on it already so hopefully the valve lash doesn’t change much more. I went with the Manley +1mm valves since supertech valves have worn down too quickly for other people in the past.

However this is a good resource for anyone else in the future if they stumble across this thread. Also, if I’m not happy with where the lashes end up I’ll order the next few lashes on that site for more control. Thanks!

 

Another option is to have a local machine shop surface grind any larger than required sizes down to the size you need.
I put the surface ground side down into the cap, but I don't really know if the surface ground side will wear quicker.
I have seen others manually sand as well, as long as it's just a small amount.