how does milling the cylinder head affect the valve timing??

Bru · 06-04-2022, 07:18 PM

Here are some photos of a uncut and a cut head. The more you cut a head the flatter that rounded part under the thermostat standpipe connection gets. It's something to look for when buying a head. I had my head and block resurfaced and ended up using an old school metal shim gasket under the Toyota factory gasket. I sprayed the bottom of the shim gasket That contacts the block with Prematex copper spray. After 7 years and 35K miles, I haven't had any issues. Alternatively, you could use a thicker stacked metal head gasket alone but you really need to prepare the surfaces first. Here is a link to a company that can supply most any thickness of shim gasket you want. I wouldn't go of more than 0.040" though. It's been discussed in other forums that a 0.020" cut is a small fraction of a degree out of timing. The Toyota manual allows 0.010 but doesn't say anything more than that.

Innovative machine & supply: https://innomach.com/cylinder-head-shims

cre · 06-06-2022, 03:03 AM

WOW! Resurrected after over 11 YEARS!?!

06-04-2022, 07:18 PM	#1
Bru Bone Stock w Upgrades ;-) Join Date: Apr 2010 Location: Tampa Bay Posts: 215	Here are some photos of a uncut and a cut head. The more you cut a head the flatter that rounded part under the thermostat standpipe connection gets. It's something to look for when buying a head. I had my head and block resurfaced and ended up using an old school metal shim gasket under the Toyota factory gasket. I sprayed the bottom of the shim gasket That contacts the block with Prematex copper spray. After 7 years and 35K miles, I haven't had any issues. Alternatively, you could use a thicker stacked metal head gasket alone but you really need to prepare the surfaces first. Here is a link to a company that can supply most any thickness of shim gasket you want. I wouldn't go of more than 0.040" though. It's been discussed in other forums that a 0.020" cut is a small fraction of a degree out of timing. The Toyota manual allows 0.010 but doesn't say anything more than that. Innovative machine & supply: https://innomach.com/cylinder-head-shims Attached Thumbnails Last edited by Bru; 06-04-2022 at 07:24 PM.

06-06-2022, 03:03 AM	#2
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	WOW! Resurrected after over 11 YEARS!?! __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

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