Checking valve to piston clearance

[355cid]

O.K., it's time to consult the experts! I'm at the stage of my build where I need to check valve to piston clearance and I'm wonder what is the best method? Im running MTC 78mm, 13:1 pistons and Web cams grind#227-0.383 lift, [email protected] duration, 276 advertised duration so I want to make sure nothing binds. This is my 1st Vmax build so any advise is welcome and appreciated. Thanks.

 

[355cid]

I Don't have a clue why the [email protected] highlighted when I typed it in. Just ignore it.

 

[gamorg02]

the @ and the . think its an email address. just separate with a space

 

[[email protected]]

http://www.carcraft.com/howto/116_0701_valve_to_piston_clearance/index.html

 

[Rusty McNeil]

Clay method +1, works well! I've only done it on Chevy engines like 20 years ago tho'

I'm wondering with the gaskets we're using now a days does torquing them twice, once to check clearance and once for final assembly damage the gasket in any way? I'm more anal than I use to be back then since we didn't have any instructions back then and this thought never occured to me .......Any one know? Or is it even neccesasary to fully torque the head down with a steel gasket? I'm going to be doing this too before too long

 

[[email protected]]

I'd talk to Sean to see if he may be able to provide you with the thickness of the head gasket you intend to use in compressed form. If that is the case you can bolt it together without a gasket and then just add in the figure he gives.

 

[one2dmax]

.027" for the ones we use and .032" or so for the OEM. They can be torqued twice.

Sean

 

[Rusty McNeil]

.027" for the ones we use and .032" or so for the OEM. They can be torqued twice.

Sean

Cool, Thanks Sean.

What kind of piston to valve numbers am I looking for with my set up?
And when doing the plastiguage thing on this motor do I need to torque the whole case or just the "main cap" bolts. And does it mattter if I do or don't use Yamabond between the cases when doing the plastiguage......Does the Yamabond contribute at all?

Thanks!

 

[one2dmax]

You should not need to worry about checking the main bearing clearance though you can if you want. I know these pistons sit closer to the top (stock sits about .050" from the top compared to about .015-.020" for the new ones). We have huge valve reliefs so you should never have an issue with valves clearing.

I would think the sealer would add very minimal amounts (maybe .0005 if that much).

Sean