01
The SB4 7.0 uses the Chevrolet LS7 cylinder block for
its foundation. Note the shaft in the camshaft position
here. It takes the full-length position of the original camshaft, to
ensure proper oiling throughout the engine, but has no lobes.
Instead, it will mount gears to drive the camshafts.
02
The LS7 block makes an excellent foundation for the
engine, as it features strong steel main caps and large
4.125-inch bores. Other 6.2L GM blocks feature smaller, 4.065-
inch bores. The LS7 block is also deck plate-honed from the
factory, for more precise cylinder sealing when the heads are
clamped in place.03
An internally balanced, forged
steel crankshaft with a 4.000-inch
stroke complements the block’s 4.125-
inch bores to give the engine its 7.0-liter
(428 cubic inches) displacement.
06
The engine is set up for a con-
ventional wet-sump oiling sys-
tem, including a GM high-volume pump,
which differs from the LS7’s production
dry-sump system. Note, too, the double-
row timing chain behind it.
04
Lightweight hypereutectic pis-
tons supplied by Mahle Motor-
sports enable the engine to rev quickly
to 8,000 rpm. The unique head pro-
file includes a pair of reliefs for the two
intake valves at each cylinder.07
Mercury Racing designed the
four-valve DOHC cylinder head
in-house, using computational fluid
dynamics to optimize the ports for high-
tumble airflow. Edelbrock handles the
aluminum heads’ casting. Intake air-
flow is around 380 cfm at 0.700-inch lift.
Exhaust port flow is around 240 cfm.05
The SB4 7.0 uses forged H-beam
connecting rods measuring 6.125
inches in length. Their strength and com-
parative low weight is key to the engine’s
high-rpm durability.08
The 71.2cc combustion cham-
bers process the airflow drawn
in and out by 1.70-inch intake and 1.38-
inch exhaust valves. The exhaust valves
are angled a little steeper to reduce the
heads’ overall width. The comparatively
large chambers still support an 11.7:1 com-
pression ratio that enables the engine to
run on premium pump gas.VETTEWEB.COM 53