[cr480r]

might catch hell for even mentioning this, but IMO you can figure deck height fairly accurately with a dial caliper. when i originally assembled my engine(350 sbc) i borrowed a friends deck bridge and indicator to check mine. They were found to be .010-.011 in the hole.. the other day just for curiousity i had a degree wheel on and rotated it to bdc. Using the leg on my caliper i measured from the deck surface to the piston edge inline with the wrist pin. 3.491"... - 3.48" stroke = .011" ...thats close enough for gasket selection purposes. Beware if you tried this method at TDC the chamfers would ruin any hope for accuracy..

[techinspector1]

Originally Posted by cr480r

Beware if you tried this method at TDC the chamfers would ruin any hope for accuracy..

As I say often, this stuff ain't rocket surgery
All you would need to get a very accurate measurement at TDC is a small framing square. Maybe I'm saying it wrong, but it's the flat measuring rule that is shaped like an L. Sit one side of the square down on the deck and butt the side of the dial caliper up against the other side of the square and measure with the slider on the caliper. There's room at the tip of the caliper to make contact with the deck and also to reach the crown of the piston with the slider part of the caliper.

[cobalt327]

After rocking the crank/piston to establish that you're at TDC, tap the top of the piston to seat the bearing against the crank journal. It won't make much difference (not more than ~ 0.002"), but it helps w/accuracy if you're measuring the all four corners to get a rough estimate of what the decks look like for being square.

[0trbo4myCHEVUICK]

Okay I will. What if we assumed all were within the. 037 -. 038 range? Just until I get it
to a position to measure all four..

[cobalt327]

Well, it wouldn't be good news, that's for sure. Getting a decent quench w/that much piston deck height isn't going to happen, not as things currently stand.

You have the option of one or more:

• shaving the decks
• using a taller compression height piston. If you have rebuilder pistons w/a 1.54 CH, that can gain you 0.020" (piston closer to deck)
• thinner head gaskets. The thinnest are 0.015" steel shims, they need a flat surface on both sides to seal to. The finish is important, too. That usually means a clean-up skim off the decks and heads for best results.
• You also could build it w/a less-than-perfect quench. Using a thin composite gasket (0.026-0.028") and your pistons you'd end up with about 0.065" quench. Definitely not ideal but I've seen worse. Not saying to do this, just saying.

[techinspector1]

Originally Posted by 1Gary

Technically the chamber volume includes the space between the deck the top of the top ring.In cases where you where right at the rag-get edge of a limit then that would be important. Some piston companies move the top ring down because of the application and heat issues.

The OEM's have been moving the top ring up closer and closer to the crown just because of what you have addressed. The mixture that sits there between the piston and the bore never gets lit, so when the cylinder is evacuated, the unburned mixture contributes to dirty emissions.

[0trbo4myCHEVUICK]

wonderful

[1Gary]

Is your state/area emissions sensitive??.

[0trbo4myCHEVUICK]

Originally Posted by 1Gary

Is your state/area emissions sensitive??.

No. Currently, no.

[0trbo4myCHEVUICK]

Not for a 30 year old antique anyways.

[0trbo4myCHEVUICK]

Just got home with the motor stand, got the motor on the stand. Post measurements soon....

[0trbo4myCHEVUICK]

.038 on all four corners

[cdminter59]

Well looks like you are going to have to use these Fel-Pro head gaskets. Fel-Pro Performance Head Gaskets Q1094 - SummitRacing.com. With these gaskets your quench will be .053. Could be worst. Static compression is 9.701 and DCR is 7.976 with 64cc heads. With 59cc heads 10.263 and 8.426.

[0trbo4myCHEVUICK]

Thats too high of compression isent it? Especially with more than ideal quench distance? I'm not sure what im going to do. Not even sure how hard it would be to disassemble the short block, send it to get decked, then reassemble. Obviously if I dont know how hard it is I have never done it and im pretty nervous about it. Im pretty certain I dont want to put it together like this. Pretty sure I need lower compression as well. Who knows what ill do. Probably end up selling this damn thing and getting something else.

[techinspector1]

Originally Posted by 0trbo4myCHEVUICK

Thats too high of compression isent it? Especially with more than ideal quench distance? I'm not sure what im going to do. Not even sure how hard it would be to disassemble the short block, send it to get decked, then reassemble. Obviously if I dont know how hard it is I have never done it and im pretty nervous about it. Im pretty certain I dont want to put it together like this. Pretty sure I need lower compression as well. Who knows what ill do. Probably end up selling this damn thing and getting something else.

You'll have the same issues with "something else"
Building a motor is not just bolting on a bunch of parts and hoping for the best, not if you want to do it properly and have a quality piece at the end. I have put motors together 3 or 4 times and had them back apart, fixing stuff and making changes and I'll bet other builders will tell you the same thing.