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Thank you everyone who chimed in. Gave me a lot to think about and made me realize I may have made a few mistakes and false assumptions when bolting the heads on, so I've decided to take a step back and verify some of the critical measurements before going any further with the rebuild.

One mistake was in a suggestion from a friend...who btw is a great mechanic & he meant well, but he's not much on the engineering side. He suggested the Fel Pro 0.037" composite gasket to reduce compression to run on pumped gas. I now realize this is most likely a bad choice at the sacrifice of quench, not knowing for sure if the heads were surfaced, and whether the CC's are equal across all chambers.

The plan is to remove the heads and cc all 8 chambers. A question I have is... once I know this, how close to each other should they be, and what is the best approach to equalizing them?

The second step is to measure the actual quench area across all 8 pistons (both ends and center of piston) to head using the rosin core solder method I've read a lot about. I believe once I know this, I can select the appropriate compressed head gasket thickness.
A few questions;
1) should I make the measurement without gaskets and the heads completely or lightly torqued?
2)Once I have this measurement, where in the 0.035"-0.040" quench area should I strive for...the 0.035" minimum or stay on the safer side of 0.040"? For instance, if I measure 0.018" quench without a head gasket, by using the compressed steel 0.020" gasket, I would be at 0.038" Considering the KB236 pistons, Eagle rods, average rod bearing clearance, and a rev limit of 6000-6500, this would be a good choice.



I wouldn't worry too much about making the chambers equal unless they are really far apart , the IMPORTANT measurement is the distance from the head deck to the cast area that is the open part of the chamber , they are NEVER the same or even flat in any direction ... at least not that I have ever measured on any of the heads I have machined.

As far as the .037 Felpro composite , no such animal , they are .040ish and you do not have a bunch of different thicknesses to choose from. Steel shim head gaskets run .021 for the most common gasket , Cometic has one that is .027 $$$$

You need to know how far above the block deck the step of the piston is sitting , no gasket.

Was the block SQUARED during any of the rebuild processes ? If not that will add to the fun. Don't be surprised to see the steps not all at the same height , even if the block was squared.


Shoot for . 040 , and hope for between .035 and no more than .045, if the heads were never cut you'll need a step that is roughly .0080 above the deck ... assuming a .021 head gasket and .100 chamber depth.

Measure the head bolt boss under the exh ports , uncut heads will be basically 1.000 , if the heads have not been surfaced they should be so you know they are flat, you can take material off the head decks to get quench , but that is going to raise your compression ratio. don't be surprised to get chamber volumes of 90-92 cc.

also make note that KB , and most aftermarket piston makers for mopar think everyone has blocks that have been decked about .020 when calculating compression ratios and picking a compression height.