Because of the difference in “STOCK” piston configurations between the Ecotec 2.4 LE5 flat top 10.5:1 compression ratio and the other engines that are currently allowed in D-2 racing, are at lower compression, the Gator Dirt Nationals sanctioning body sees the need to allow all engines to run a “Flat Top” 4 eyebrow piston, stock or aftermarket, so no 1 engine has a compression ratio (HP) advantage. This also will help ease any piston tech issues by pulling a plug and looking with a scope.
Case in point:
LE5 Ecotec 2.4 L - 2,384 cc (145.5 cu in) Flat Top piston
2006–2009 - Saturn Sky - 177 hp @ 5800 rpm - 173 lb·ft @ 4800 rpm - Comp: 10.5-1 - Rev Limit: 7000 rpm
Honda 2.4 L - 2,354 cc (143.6 cu in) Dish piston
2005-2006 - Honda CR-V - 156 hp @ 5900 rpm - 160 lb·ft @ 3600 rpm - Comp: 9.6:1 - Rev Limit: 6500 rpm
Ford: 2.3 L - 2,261 cc (138.0 cu in) Dish piston
2001–2011 - Ford Ranger - 164 hp @6000 rpm - 144 lb·ft @ 4000–4500 rpm – Comp: 9.7:1 - Rev.: 6500 rpm
Chrysler: 2.4 L - 2,360 cc (144 cu in) Flat top piston
2013- present - Dodge Dart - 184 hp @ 6250 rpm - 174 lb·ft @ 4800 rpm - Comp: 10.0-1 – Rev.: 6800
Toyota: 2AZ-FE - 2.4 L 2,362 cc (144.1 cu in) Dish piston
2002–2011 Toyota Camry - 160 hp @ 5600 rpm - 162 lb·ft @ 4000 rpm – Comp: 9.6:1 Rev.: 6500
GM Quad 4: 2.4 L - 2,390 cc (146 cu in) Dish piston
1988–1994 - Pontiac Grand Am - 150 hp @ 5600 rpm - 155 lb·ft @ 2400-4400 rpm - Comp: 9.7:1
This is "NOT D-2" making this change.... this is for the Gator Dirt Nationals
complete rules at www.ssmidgets.com/gd-nationals.html