SBM Edelbrock/Speedmaster Head Data
Here's some recent test results on the Speedmaster head. First modification is a small 75 degree bowl cut between the factory 90 degree bowl hog and 60 degree bottom cuts. Results are shown with an Edelbrock 1 angle valve.
Second test was just experimenting with the shape of the stock combustion chamber. Clay was added in the combustion chamber to form a 35 degree top cut 'cone' around the perimeter of the intake valve. The picture shows the clay in the chamber with a 35 degree plastic 'squeegee' that was used to form the clay. Where shrouded (the cylinder wall side), a 4mm radius was also added to smooth the transition to the chamber wall. The spark plug was completely covered, and clay was also extended over the quench pad. Obviously not a usable design, but it made for an interesting test. Results shown with Edelbrock 1 angle valve.
Last test was adding a Ferrea 30 degree back cut valve to the head with the 75 degree bowl cut and the clay chamber.
This post is for information sharing only. I am not qualified to interpret the results.
Here's some recent test results on the Speedmaster head. First modification is a small 75 degree bowl cut between the factory 90 degree bowl hog and 60 degree bottom cuts. Results are shown with an Edelbrock 1 angle valve.
Second test was just experimenting with the shape of the stock combustion chamber. Clay was added in the combustion chamber to form a 35 degree top cut 'cone' around the perimeter of the intake valve. The picture shows the clay in the chamber with a 35 degree plastic 'squeegee' that was used to form the clay. Where shrouded (the cylinder wall side), a 4mm radius was also added to smooth the transition to the chamber wall. The spark plug was completely covered, and clay was also extended over the quench pad. Obviously not a usable design, but it made for an interesting test. Results shown with Edelbrock 1 angle valve.
Last test was adding a Ferrea 30 degree back cut valve to the head with the 75 degree bowl cut and the clay chamber.
This post is for information sharing only. I am not qualified to interpret the results.