I was shoting for zero deck hight.. Well I got the block back and I got zero deck height...and above deck height. depending on what side of the piston I am checking. Not by much, but some. Also I don't have enough rod bearing clearance. So I'll remeasure after I buy new bearings. Is the extra 10 thou going to drop the piston in the bore.

 

Is your piston to cylinderwall clearance correct? If it is too large the piston will "rock" back and forth and not be straight up at top unless you manually straigthen it. New bearings + oil will not "lower" the piston but you can use a slightly thicker head gasket if you like. Make sure you measure rod bearing clearance with your new bearings before you button it up. Good Luck!

 

How far off are you on the rod bearing clearance? If it is under a thousandth, consider polishing the journals instead. On my engine, we plastigauged all rods and mains, then polished the crank to get everything matched down to a ten thousandth.

 

What gasket/squish were you planning on?

 

Here is a list of just about every head gasket available for Chevy engines. Includes bore, compressed thickness and the CC's for computing compression ratio.


PART #.......... BORE.....THICKNESS........CC's

FEL-PRO
Small-Block
1003.............. 4.166........... 0.041........ 9.1
1004.............. 4.190........... 0.041.........9.2
1010...............4.166........... 0.039........ 8.9
1014.............. 4.200............0.039........ 9.0
1034.............. 4,200........... 0.041........ 9.3
1043............... 4.080.......... 0.039......... 8.2
1044............... 4.200...........0.051.........11.2
1094............... 4.100...........0.015..........3.2
Big-Block
1012................4.640...........0.03 9.........10.0
1017-1.............4.540...........0.041..... ....10.9
1027............... 4.370...........0.039.......... 9.7
1037............... 4.370...........0.039...........9.7
1047................4.540...........0.03 9..........10.5
1057............... 4.630...........0.041..........11.3
1067................4.630...........0.03 9..........11.0
VICTOR REINZ
Small-Block
3514SG......... 3.840............0.045..........8.4
5746.............. 4.100............0.026..........5.4
+1178SSB..... 4.100........... 0.020..........4.1
+1178SG....... 4.160............0.045..........9.8
3432SG..........4.190............0.045.. ........10.0
1178SCR........4.190............0.044... .......9.8
3512.............. 4.190............0.040..........8.8
Big-Block
3884SG......... 4.520........... 0.045..........11.5
5950SC..........4.370............0.042.. ........10.0
5946SC......... 4.630............0.042..........11.2
4886.............. 4.578............0.042..........11.0
4918...............4.578........... 0.042..........11.0
5951 SC........ 4.370............0.042..........10.6
McCORD
Small-Block
94-2010.......... 4.140............0.042..........9.3
94-2011.......... 3.840............0.042..........8.0
94-2017.......... 4.190............0.042..........9.5
Big-Block
94-2013...........4.370............0.042... ......10.3
ROL
Small-Block
HG31010HT...3.825............0.051...... .....9.6
HG31600........4.090........... 0.020.......... 5.4
HG31000HT... 4.175.......... 0.044.........11.4
HG31250HT....4.200 .......... 0.051.........11.6
Big-Block
HG31170HT... 4.345 ...........0.044..........12.4
MR. GASKET
Small-Block Solicor
5727................4.190........... 0.044..........9.8
5728................4.220........... 0.042......... 9.3
Big-Block Solicor
5730............... 4.370............0.042..........10.2
5731............... 4.630............0.042..........11.2
5732............... 4.370............0.042..........10.6
5733............... 4.540............0.042..........10.8

 

I think things are better now. I didn't account for piston rock since i thought the rings eliminated it. The guys at www.chevelles.com clued me in. I ran out and did the measurments again using your method. i am much more happy now. Still one hole seems a little high but nothing that i would think is out of range.

 

The reason I ask about the squish is that's what limits the static CR you can have with the parts you have available.

If you are drag racing, I agree with Mr Vizard, you can run a 25 to 28 thou squish with a well built engine. For fast street or endurance engines, 35 thou is more like it. Knockabout shade tree rebuilds, stick to 40+.

The tighter the squish, the better the engine will be for the quality of burn, knock resistance, volumetric efficiency and thus torque. My 327 is going to run as little as I can get away with above 30thou because my heads have quite large chambers for a 327 and I don't particular want to machine them to get the CR up. I think I'm fighting a losing battle there, but we'll see when I measure the heads.

Low squish was also a reason for me to stick with 23deg heads - I wanted to use a relatively plain-Jane piston with 23deg recesses already cut. I'm still going to have to clearance check each one, but since my short-block is being done by a race shop, I expect very tight grouping on the CHs in the bores.

I am so looking forward to being where you are now with your block. It looks soooo funky.

Mark.
(I love this hobby.)

 

I will play it safe and shoot for minimum.035 squish on this engine. Maybe a touch under depending on my gasket choices. This should be a high reving street engine making about 11 to 1 compression with a healthy lunati solid cam, shaft rockers and free flowing exhaust ( I hope ) . I don't care if i need to mix in race gas so that gave me some more leeway..

 

Thanks Buns your a wealth of information!