Are those pistons flat topped or do they have any
dome,Larry? Most standard 396 pistons of the 1966-1970 era were at least 10.25:1
compression and weren't flat topped. The 375hp L78 units were 11.0:1
compression. Anything over 10.0:1 with cast iron heads is pushing it with
regards to detonation. Aluminum heads allow you to run a half to full point
higher. Anyway,getting back to your L78 heads,,those are rectangular port
units that aren't very efficient below 5,000 rpm. If I were building a pure
street motor,I would sell or trade them for a good pair of 781 or 049 oval port
castings. These would really improve the engine's street manners by flattening
the torque curve,work well with the lower compression needed for pump gas,and
will improve the fuel mileage over the rectangular units,too.
Something else to consider is the rpm limits of
those rectangular port heads will tax the limits of that two bolt 396 block,if
you decided to build a screamer BBC to take advantage of the superior high-rpm
power of the heads.
However,it all boils down to what you want to do
with that 396.
Clint Hooper
H&H Custom,owner 1969 El Camino ProTourer 2001 H-D FLHR custom bagger http://dalesplace.com/misc/friends/clint/clint_hooper.htm
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- Re: [Chevelle-list] 396 Rebuild - Piston Question Clint Hooper
- Re: [Chevelle-list] 396 Rebuild - Piston Question Larry Shouse
- Re: [Chevelle-list] 396 Rebuild - Piston Question Clint Hooper
- Re: [Chevelle-list] 396 Rebuild - Piston Questio... Larry Shouse
- Re: [Chevelle-list] 396 Rebuild - Piston Que... Clint Hooper
- RE: [Chevelle-list] 396 Rebuild - Piston Question Dale
- Re: [Chevelle-list] 396 Rebuild - Piston Questio... Clint Hooper