3x00 shims...

[Superdave]

So has anyone found a better shim to use with LS6 springs on the newer 3400 heads?

I could use SBC shims again but i'd like something like the originals so that it keeps the springs centered...

[treeZ24]

make a jig and mill them they should be bang on

[AaronGTR]

Been covered before. Why would you use SBC shims if they don't keep the spring centered. You can use LS1 shims and just grind out the center hole so it fits over the guide. Also the shims from a '81-87 toyota land cruiser (engine code 2F) are supposed to have the same diameter hole for the guides. I haven't tested this personally since my heads had the smaller guides, but someone on this site used those and the chrysler 318 valve seals on their heads with the larger guides and said it worked.

[SappySE107]

I use isky seats. The are .060 thick and fit the guides perfect. I machine the heads down .060 for them as well. I just bought a set (they come in 16s) and now have finished up another set from my leftovers. They aren't cheap though so even at a fair price for 12 Id have to sell them for $50 shipped. Part number is 950-VSL, perhaps you can find them cheaper.

[Superdave]

Meh, i just re-used the .015 SBC shims again.

I tried some shims from a set of 2.8 heads, they're so close that it's not funny...

I didn't have a problem with the SBC ones and my LS1 springs, i'm sure they'll be fine with the LS6's...