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5.0 and 5.7 cyl. heads

jrwms said:
Are 5.0 and 5.7 cyl heads interchangeable
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Short answer.... yes!

Long answer...... DO NOT arbitrarily change to a different cylinder head without knowing full well what the piston profile is!

The cylinder head combustion chamber volume must compliment the piston dish volume and visa-versa.

Also, there are many different valve diameters, light and heavy castings, intake running sizes, intake manifold bolt angle changes, Vortec -vs- Non-Vortec, etc.


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Accidentally took the wrong head of the shelf and put the 305 head on my 5.7 it's done it runs I didn't check the casting numbers am I going to run into problems down the road. I can go back to my.sons shop and check casting numbers.
 
Here's an example of what may become an issue:

GM starting using the SBC full dished piston in cars/trucks in the early 70's.
It solved emmission control issues, and they learned that one single piston part number fits all eight bores.
The GM bean counters loved this idea!

The high performance engines did not receive this piston.

With the full dished piston, the cylinder head's combustion chamber became smaller to accomodate the piston deck volume.
Many were 64/65cc in volume.

Unfortunately, this carried over into the Marine SBC.

With the earlier flat top pistons, the cylinder head chamber volume was commonly larger... around 76cc or so, depending on the intended use.

So.... if you installed 76cc chambers over full dished pistons, the static compression ratio will be too low.

Conversely, if you installed a 65cc chambers over a flat top pistons, the static compression ratio would be too great for Marine Cruiser use.

If you installed only one cylinder head, and if that cylinder head's chamber volume was not the same as the other head, you may have an additional problem.


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