Modded Mustang Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
34 Posts
Discussion Starter · #1 ·
.







anyone know what the difference between Dished and Flat Top pistons?:sorry







.
 

·
Registered
Joined
·
2,817 Posts
they are exactly what they sound like. A dish piston actually has a small dish to it. A "flat top" piston actually is just that, a flat top on it. It is all used for compression ratios mostly. The deeper the dish, the less the compression. Flat tops will yield a higher compression ratio. Stock pistons IIRC are 6.5cc dish, which produces a 9.8.1 compression ratio with our cylinder heads. If you are building a supercharged/turbo motor, you want a lower compression than a naturally aspirated motor.

There are OTHER things that help determine compression ratios. The cylinder head also plays a big role in it. A 50cc cylinder head will have a higher compression than a 60cc head. The combustion chamber is made up of the cylinder head and piston area......(both play a role in compression ratios).

Pistons will also sometimes (ALOT of times with modular motors) have valve reliefs cut into the tops of them. These are provisions cut out of the top of the piston for extra valve clearance.
 

·
Registered
Joined
·
6,471 Posts
they are exactly what they sound like. A dish piston actually has a small dish to it. A "flat top" piston actually is just that, a flat top on it. It is all used for compression ratios mostly. The deeper the dish, the less the compression. Flat tops will yield a higher compression ratio. Stock pistons IIRC are 6.5cc dish, which produces a 9.8.1 compression ratio with our cylinder heads. If you are building a supercharged/turbo motor, you want a lower compression than a naturally aspirated motor.

There are OTHER things that help determine compression ratios. The cylinder head also plays a big role in it. A 50cc cylinder head will have a higher compression than a 60cc head. The combustion chamber is made up of the cylinder head and piston area......(both play a role in compression ratios).

Pistons will also sometimes (ALOT of times with modular motors) have valve reliefs cut into the tops of them. These are provisions cut out of the top of the piston for extra valve clearance.

repped
 
1 - 11 of 11 Posts
Top