Did you mean 10.10 to 1?

 

No, unless my brain is completely gone this morning.
I was just double-checking my spreadsheets,
I had stock down as 10.44:1, my current setup at 11.10:1

......................(Units).....Stock........... .....Current
........................
Bore....................in........4.000........... .....4.000
Stroke..................in........3.480........... .....3.480
Combustion Chamber......in^3......3.539................3.539
Piston Volume...........in^3......0.275................0. 275
Deck Height.............in........0.015................ 0.015
Head gasket Thickness...in........0.050................0.026
----------------------------------------------------------------
Compression Ratio........:1.......10.44350603........11.101385 29

 

You would be suprised that 11.7:1 SCR works well on pump gas in a LT1.

Bret

 

Sounds like chamber size is not the same for all LE2 applications. My LE2 chambers, set up for a 355, were definately between 54 and 55cc, not 58. After my numbers were widely questioned, the shop verified my measurements. This was on stock heads not previously milled. So, you NEED to check you own heads before planning further; don't just assume. It's easy with the heads off. Or your shop can do it cheap. Mine didn't even charge me, just to verify one chamber.

 

From the looks of my heads, it does not look like Lloyd removed a lot of area. It appears he just smoothed out the existing combustion chamber. I was told he removed .010" of surface from the heads.

I found my heads specs but no mention of the head volume.

There would have to be a lot of metal taken out to get the 58CC chambers like some have said. It is my guess that they are very similar to what they originaly were.

I wish I had a burette or whatever that thing is called right now.

 

You can do it all with a quick run to the hardware store and drugstore. I used a 30CC syringe from the drugstore, but pet shops have them too. Bigger would be better but 30 was all I could find.

Get a piece of sturdy clear plastic, like 1/4 inch plexiglass. You will need to get it to fit flat over the chamber, but the valves will be in the way. So, carve little 'eyebrows' in the plastic to just barely fit over the valves. Dremel is good, use whatever you have. Drill 2 holes in the plastic, one at one end of the chamber for the syringe to fit, and another at the other end to let air out.

Put a spark plug in the chamber you are going to measure.

Put a ring of grease around the chamber so the liquid will not leak out around the edges. It needs to seal completely, but not seep into the chamber or the measurement will be off. This step is important and will probably take a couple of tries to get it just right.

Now, seal the chamber with the plastic piece and a couple of big rubber bands or whatever, and set the head almost level but with the air exit hole slightly higher than the syringe hole. Fill with liquid of choice and measure until completely full. Do it 2 more times and make sure you are getting the same answer. That's it. W/S washer fluid is nice because it is tinted, but I've used plain water.

Have fun.

 

Engine builder measured my LE2 combustion chambers.
They are 50cc on the money.

With the .029 Impala head gasket my CR was 11.6 which is a tad higher than I wanted. I am going with the .039" Fel-pro gaskets to get the CR down to 11.1

 

I had lloyd CC my heads, they came out to 55.6 CC's.

 

My builder cc'd my LE2s at 53-54cc.

 

Back from the dead!!

A lot of people are unsure of the stock specs and I just measured mine myself and I can BARELY get 54 CCs in the stock head. Just thought I'd add that to this thread.

 

thank you because there have been numerous threads on this, but when people measure their heads, they come out to near 54CC. thanks again

 

Maybe Lloyd can chime in here.
If the stock chamber is 54cc, and the head is milled .010" that means that it must now be <54cc. I know Lloyd does some smoothing of the chamber so that should increas the size a tad bit. The engine guy that checked mine swears that they came out at 50c in the end after Lloyd has completed the job.

Edit: They were shaved .010"

 

How much were yours shaved?

 

I wish complete specs would have been included with the heads we receive from Lloyd.

Chamber cc information, flow graphs, spring heights, etc would have been nice to know.

 

The engine should be built around the heads. As in.. once the heads are in your hands you then have the chambers CC'd to make sure they are correct and then you create your desired compression.