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Classic Austin Mini Cooper 73.5mm , 1380 powermax piston 9cc dish - SINGLE

Classic Austin Mini Cooper 73.5mm , 1380 powermax piston 9cc dish - SINGLE

Classic Austin Mini Cooper 73.5mm , 1380 powermax piston 9cc dish - SINGLE
Selected: 73.5cc Powermax with 9cc dish
Part No: 20659-STD-EA
Fits the following:
Classic Mini
Sprite & MG Midget
Morris Minor
Alternate Products
Austin Mini 73.5mm Evolution Piston With 9cc Dish Sold Each
$156.95 Austin Mini 73.5mm Evolution Piston With 9cc Dish Sold Each
For the ultimate in engine performance, these pistons, installed in a 1275cc block, will blow your doors off! You can't beat cubic inches for performance, and the A-Series block can be bored far bigger than the factory ever imagined. The stock bore is 70.6mm, the 1380 bore is 73.5mm. This is .120" oversize and still leaves room in the block to go to 74mm (1400cc), but only if you offset bore prior to going to 73.5mm. These 73.5mm pistons from Nural (Federal Mogul) are great for street and mild racing.
Top ring is 1.47mm height
second ring is also 1.47mm
Oil ring is 4mm in height 73.mm bore size is 2.8973", Pin height is 1.4875. Top 2 rings are 1.5mm height (.0591"), oil ring is 4mm (.1575")
Pin Height- 1.47"
What are the potential compression ratios with this piston?
They are around 9.5 to 10.5 but that depends also on which head.

Mini Mania Tech Team

The Classic Mini Parts and Accessories Experts

Related Technical Articles:
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