The 1.7 liter positive displacement blower certainly is compact and although it is smaller than the C6 ZR1's supercharger it spins to a higher 20k rpm. GM argues that the blower comes on power quicker due to the lighter weight rotors but a bigger blower will certainly make more power more efficiently without needing to be spun as hard. It's a bit of a give and take.
Here are some additional specifications on the motor from GM:
The new LT4 engine is based on the same Gen 5 small block foundation as the Corvette Stingray’s LT1 6.2L naturally aspirated engine, incorporating several unique features designed to support its higher output and the greater cylinder pressures created by forced induction, including:
- Rotocast A356T6 aluminum cylinder heads that are stronger and handle heat better than conventional aluminum heads
- Lightweight titanium intake valves
- Machined, forged powder metal steel connecting rods for reduced reciprocating mass
- High 10.0:1 compression ratio – for a forced-induction engine – enhances performance and efficiency and is enabled by direct injection
- Forged aluminum pistons with unique, stronger structure to ensure strength under high cylinder pressures
- Stainless steel exhaust manifolds and an aluminum balancer that are lighter than their LT1 counterparts
- Standard dry-sump oiling system with a dual-pressure-control oil pump.
The 1.7L Eaton supercharger is more compact than the one found on the LS9 and it spins at up to 20,000 RPMs – 5,000 more than the ZR1 too. The smaller rotors spin up faster which enables the boost earlier in the RPM band.