Augusto,

For the Brazilian Chevrolet 250 with carburetors and 3 siamesed intake ports, the pistons for the Chevrolet small block 307 V8 work. They have the proper bore 3.875" and compression height. Forged pistons for the Chevrolet 307 usually are not stocked by the major piston manufacturers anymore. They can be special ordered or found in smaller companies individual inventories. For example, here's a link:

http://www.12bolt.com/250292_inline_products/pistons


The later '92 to '95 fuel injected Brazilian 250's use 6" connecting rods versus the earlier engine's 5.7" connecting rods. So the piston compression height is shorter on the later engines. There is not a stock USA piston available for the later 250 series Brazilian engine.

The 17º and 23º you mentioned refers to the valve stem inclination angle, related to the wedge combustion chamber used on small block V8 engines. The Chevrolet 250 cylinder head combustion chamber is more of a bath tub shape with much less valve inclination than a wedge cylinder head used on small block V8 engines.

Last edited by Winter; 08/19/11 07:48 AM.