20V shim Micrometer

User avatar
oldeskewltoy
Club4AG MASTER
Posts: 2180
Joined: Wed Jan 09, 2013 4:44 pm
Location: Portland, Oregon

20V shim Micrometer

Postby oldeskewltoy » Tue Feb 21, 2017 12:06 pm

Image

Fowler 1/2" caliper 52-230-000-0

• 0-1/2" micrometer by .001", Satin chrome finish.
• Forged steel frame
• Anvil and spindle hardened and precision ground with microlapped ends
• Clear, crisp graduations on barrel and thimble.
Diameter of measuring faces: .197"
• Flatness: .00003"
• Parallelism: .00005"
• Accuracy: .001"
• Range: 0-1/2"
• Includes case


The diameter of the measuring faces of this caliper =.197", which = 5mm. So if you are doing valve adjustment on 20V head[s], you may want this tool to check shim thicknesses.
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

allencr
Club4AG Expert
Posts: 394
Joined: Thu Jan 10, 2013 9:59 pm

Re: 20V shim Micrometer

Postby allencr » Thu Mar 02, 2017 6:32 pm

Drop a ball bearing in there, it sure saves winding that thing back & forth.

User avatar
oldeskewltoy
Club4AG MASTER
Posts: 2180
Joined: Wed Jan 09, 2013 4:44 pm
Location: Portland, Oregon

Re: 20V shim Micrometer

Postby oldeskewltoy » Tue Dec 19, 2017 9:20 am

works for me.... managed to get this clients 20V to the tighter side of the spec, then the looser side it had been.



Image


Exhaust were .018"-.020", they are now much closer to the tight end with 7 between .015", and .016", and a single one @ .017" - because I didn't have another shim that was either .001", or .002" thicker then the one in there, and while a tiny bit looser, it is still .003" tighter then it was when it came to me. On the intake side - all the clearances are between .007 and .008, they ALL had been .011"


Biggest problem I need to solve - a method to mark the shims so I don't have to constantly remeasure... also.... Need to get more shims... AND a 20V shim box ;)
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

jdm86gtz
Club4AG Expert
Posts: 307
Joined: Fri Jan 11, 2013 10:13 pm
Location: Ireland

Re: 20V shim Micrometer

Postby jdm86gtz » Tue Dec 19, 2017 4:12 pm

oldeskewltoy wrote:Biggest problem I need to solve - a method to mark the shims so I don't have to constantly remeasure... also.... Need to get more shims... AND a 20V shim box ;)



I tape each shim and write on the masking tape