Decking Height checking the head?

[DeadLastRacing]

The white piece Im measuring is clay. I clay tested the turn over of the Valves and the piston. They pushed down to 3/16 of an inch )4.66mm or .1835"). Isn't this gap WAY to big?

What head gasket should I buy? Or is my decking way the f outta wack?

 

[87warrior917]

Did you put it together with no gaskets tocheck this? Your gonna have clearance for sure, it may seem like alot but once the motor is hot and everything zingin high rpms its gonna stretch and make the clearance tighter. I say run it and get you damn quad together hah!

 

[Gen1Pat]

Cometic EST is .007-.010" thinner than stock. I don't know what the base thickness is.

 

[jasonp]

Really making this out to be harder then it is.

Simple way is to take a straight edge across the cylinder with no gaskets installed. Take your feeler gauge and measure the top of the piston right at the piston pin location on the side where the piston is flat.

Take that measurement, say it sits above the cylinder sleeve .010". Then you would order a .010" base gasket and .040" head gasket.

If the piston sits above the cylinder then you will have to measure, straight edge off the piston to cylinder which might be harder.

With no gaskets does and your piston installed with the cylinder how far does your piston come up to the top of the cylinder?

You can also you a dial digital caliper.


Anything more then .040" you will loose compression and performance.

 

[jasonp]

Cometic EST is .007-.010" thinner than stock. I don't know what the base thickness is.

What is the stock gasket thickness?


Just an FYI EST gaskets can be ordered in what ever thickness you want. Same goes for the base gasket. If you are spending the mone you might as well get the correct ones.

 

[DeadLastRacing]

Really making this out to be harder then it is.

Simple way is to take a straight edge across the cylinder with no gaskets installed. Take your feeler gauge and measure the top of the piston right at the piston pin location on the side where the piston is flat.

Take that measurement, say it sits above the cylinder sleeve .010". Then you would order a .010" base gasket and .040" head gasket.

If the piston sits above the cylinder then you will have to measure, straight edge off the piston to cylinder which might be harder.

With no gaskets does and your piston installed with the cylinder how far does your piston come up to the top of the cylinder?

You can also you a dial digital caliper.


Anything more then .040" you will loose compression and performance.

OK, I'll try this again. I always though we were talking about valve to piston clearance (which is what I measured).

ANYWAYs, the .40mm that I want, is the gap from the top of the cylinder to the top of the piston at TDC. NOW I get it.

I do this measurement with NO gaskets at all (base or head) correct? (What I measured here still has the base gasket on it, no head gasket)

Its my first "Real" go around at this and I just want to get the max power out of it all that I can. I have rebuild 5 warrior engines in my life and never really checked deck or valvel heights before. just bought parts and put it all together and go. Hahaha

ON a side note, what is the minimum valve to piston clearance? Just as close as you can get without hitting?

 

[DeadLastRacing]

get you damn quad together hah!

Soon very soon. Still waiting on shocks! :argh:

 

[jasonp]

OK, I'll try this again. I always though we were talking about valve to piston clearance (which is what I measured).

ANYWAYs, the .40mm that I want, is the gap from the top of the cylinder to the top of the piston at TDC. NOW I get it.

I do this measurement with NO gaskets at all (base or head) correct? (What I measured here still has the base gasket on it, no head gasket)

Its my first "Real" go around at this and I just want to get the max power out of it all that I can. I have rebuild 5 warrior engines in my life and never really checked deck or valvel heights before. just bought parts and put it all together and go. Hahaha

ON a side note, what is the minimum valve to piston clearance? Just as close as you can get without hitting?

Check the cam manufacture on p to v clearance. I believe it's .060" for most.

Yes the distance for the non raise portion of the piston (wrist pin area) to the top of the sleeve or cyclinder with no base or head gasket so you can calulate how thick the base and head gasket need to be. I've run, .033" total no problems until you start advancing cam timing but with your cam I wouldn't worry about it.

 

[DeadLastRacing]

Check the cam manufacture on p to v clearance. I believe it's .060" for most.

.060mm?? HOLY YIT im still way off. My gap is huge (im a whore, hahaha). But seriously, is something messed up if I have a 3/16 gap from valve to piston gap?

 

[MidwayUSA]

.060mm?? HOLY YIT im still way off. My gap is huge (im a whore, hahaha). But seriously, is something messed up if I have a 3/16 gap from valve to piston gap?

Nothing is messed up. As long as it is not less than the minimum, it is fine. They cut the pockets on the pistons deep so that people who just put them together without checking won't hit. Ultimately you would want it tighter to keep the compression up. Short of ordering a custom piston, you really have no choice. Even if you were to order a custom piston, the measuring process to get them the info would give you a headache for sure.

Next issue is if you use thinner gaskets then you need to get an adjustable cam gear. That is another headache because you would need a degree wheel to get the cam timing back where it should be.

I would put it together and run it.

 

[MidwayUSA]

Check the cam manufacture on p to v clearance. I believe it's .060" for most.

Yes the distance for the non raise portion of the piston (wrist pin area) to the top of the sleeve or cyclinder with no base or head gasket so you can calulate how thick the base and head gasket need to be. I've run, .033" total no problems until you start advancing cam timing but with your cam I wouldn't worry about it.

Minimum piston to valve is on line one of this link:

Cam setup