How close is good enough regarding installed height

[siuauto]

I have a set of aluminum heads that I am building, and when measuring for Installed Height, I get 1.920; the spring recommended for my cam has an installed height of 1.8", So I am off by .120", but I will use a .060 spring locator, which leaves me .060 left. Can I run a shim with a locator? Is .060 worth messing with? what would you all do?

Thanks as always,

 

[TT5.9mag]

Setting installed height

Some info here.

 

[PRH]

The “easy to obtain” shims come in .015”, .030”, .060”, ……so, fundamentally you should be able to get within .015”.

I’d want to be way closer than .060” ………. Assuming the height you’re targeting provides the desired/correct spring force.

 

[siuauto]

The “easy to obtain” shims come in .015”, .030”, .060”, ……so, fundamentally you should be able to get within .015”.

I’d want to be way closer than .060” ………. Assuming the height you’re targeting provides the desired/correct spring force.

Is it acceptable to run shims with locators?

 

[RustyRatRod]

On my slant 6 unicorn head, I am within .010" from the shortest to the tallest.

 

[Bewy]

No problem running shims + locators..............but.......make sure the v/stem seal doesn't bottom out on the locator. Could happen with some heads & a lot of shims.

 

[7e5hangten360]

comp sells +.050 and -.050 locks. they have it for 3/8 and 11/32 stems. for 10 degree retainers. inexpensive. this may be your best bet.

 

[Bewy]

I have never found that the '050' locks give you the full 050...more like 035.

 

[Dave999]

You could also get offset retainers, i think crane used to do them, not sure if they are still available.

offset lock and retainer will get you there, and leave more space for the "armpit" of the rocker.
the offset retainer sat at the same position on the stem but the rim/ spring contact area, was for want of a better word, lower, basically the centre of the retainer didn't sit lower on the locks the offset was in its rim.... this you avoided a stack up of offsets that caused you to hit the stem seal at full lift which is what would happen if you moved it all physically down the valve stem.

 

[earlymopar]

I have a set of aluminum heads that I am building, and when measuring for Installed Height, I get 1.920; the spring recommended for my cam has an installed height of 1.8", So I am off by .120", but I will use a .060 spring locator, which leaves me .060 left. Can I run a shim with a locator? Is .060 worth messing with? what would you all do?

Thanks as always,

The spec that seems to be universally accepted by many engine builders is +/- .010" of the target installed height.