head spacer or machine work?
 

so i just got my block and head back from the shop and was told it might be a good idea to either get a head spacer or machine the pistons both options are about the same price. i had to take .020" off my head and .018" off my block so does anyone have any ideas as to what i should do? head spacer machine work or just put the thing together? i just dont know how close Toyota ran the pistons to the valves.

Thanks
Matt

so is there a difference between running a head shim and gasket and just running 2 head gaskets, cause as far as i can tell the head shim looks the same as my head gasket.

Shim is a single layer and generally compresses less (than a composite that is). Running a shim with a metal HG versus running a thicket metal HG is pretty much the same thing. I *think* the shim would be preferable though in your case. A real thick MHG has a lot of layers and that's a lot of potential for gaps and leaks. A solid copper HG would be the cleanest solution, but I hear longevity is an issue, hence why you really only see them on dedicated race cars.

The question I haven't seen asked or answered is what are you running now and what are your plans? What type of HG do you want to run? If your car is turbo'd are you looking to go to a thicker HG to reduce the CR?

i don't plan on doing to much i was thinking 550cc injectors and a lexus afm and may be running 10 psi and 3in exhaust, other then that it will be stock. oh and i got a full set of forged pistons that will now have to be machined down .020 to be below the deck:barf:

You could see if it would be possible increase the dish of the pistons enough to bring down the CR so you could use a thinner HG and no shim... I don't know if I would though.

Do also keep in mind you need to calculate the new CR after shaving the pistons as the dish will be lessened.