TheRobSJ
Korvettekapitän
You really think that's why the bore space is still 4.4?
Almost three decades ago, when the ZR-1 was in development, GM owned Lotus. Lotus was tapped to engineer the new high tech powerplant for the ZR-1. Why they didn't keep it in country and just use the GM Powertrain division will be a mystery. Then they tapped Mercury Marine to build it for them too. Anyways, the GM brass had several design parameters that had to be adhered to. Must be overhead cam, must output at least X horsepower, must not be any less efficient than current small block (at the time it was decreed that no GM vehicle would be subject to gas guzzler tax), and must have 4.4" bore centers so they could still call it a "small block" Chevy V8.
Lotus came back and said, yeah we can totally give you the power and the fuel efficiency...and even more if you want...just let us use different bore spacing (they wanted to use fatter pistons and go oversquare I assume). At that time it was good ol' Roger Smith in the big chair at GM that told them a big fat no because it wouldn't sell since traditions mattered.
Nowadays we're on the GenV small block. It's not a Chevy small block anymore, it's simply the small block. But they still use those 4.4" centers. I think the traditionalists are all gone out of GM. For years, thy also had a standing policy that no other GM vehicle will make as much power as the Corvette. This is why the LT1 F-Body was rated at 285(?)hp while the Corvette got the full 300 even though we know full well they dynoed almost identical. But now we have a 650hp Camaro and a 650hp Corvette.
The upcoming DOHC engine for the super duper Corvette is supposed to be 6.2L just like the existing GenV small block, which leads me to believe it's still 4.4" centers. So maybe there's more to it than tradition and Lotus was just stupid?
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