I think it’s pretty good with the flowing and porting that you’re doing. I reckon the factory V6 heads would flow roughly the same so it would be a good comparison to see the difference between your porting and then flowed.
Good video i just cleaned casting dags and bumps on my VN heads in the ports, Got neway cutters, what do you recommend the 45deg seat in/ex width to be on a street engine? Thanks
I try and aim for 0.060in seat touch, checked by machining blue for both in/ex. It's small, but with today's unleaded fuels, the seats are going to widen over time. I also used this as it was a starting point from Mr. Vizards' books about porting. So far, on the heads I have done, there are no troubles.
How much power are you trying to make with the std size valve, cracks between the valve seats on VN cast iron heads aren’t a problem just run them as is
Last (and only) set sits on a 60tho over 308 (317Cu In) and made 300hp@6000 on a hub dyno, using a 218@0.050in cam and 0.478in lift. It also has a ported Edelbrock AirGap to complement airflow. In a VC Commy it recently went 14.111sec on an unpreped country road (Car Club 1/4 Mile Sprint).
I disagree. On a flowbench, velocity (which is a restriction causing an increase in vacuum) is not the best for flow numbers. What changed is how the air enters the port, which had the effect of reducing flow through to the cylinder. Since I was only measuring a port without an intake manifold, this situation can be changed. I couldn't prove it due to not having access to a manifold.
Pretty good demonstration to watch. I’d like to see you do an L67 supercharged V6 head.
I don't have access to the supercharged one, but I do have an n/a one kicking around...
I think it’s pretty good with the flowing and porting that you’re doing. I reckon the factory V6 heads would flow roughly the same so it would be a good comparison to see the difference between your porting and then flowed.
Good video i just cleaned casting dags and bumps on my VN heads in the ports, Got neway cutters, what do you recommend the 45deg seat in/ex width to be on a street engine? Thanks
I try and aim for 0.060in seat touch, checked by machining blue for both in/ex. It's small, but with today's unleaded fuels, the seats are going to widen over time. I also used this as it was a starting point from Mr. Vizards' books about porting. So far, on the heads I have done, there are no troubles.
@@crd-nz_001 thanks for that info
How much power are you trying to make with the std size valve, cracks between the valve seats on VN cast iron heads aren’t a problem just run them as is
Last (and only) set sits on a 60tho over 308 (317Cu In) and made 300hp@6000 on a hub dyno, using a 218@0.050in cam and 0.478in lift. It also has a ported Edelbrock AirGap to complement airflow.
In a VC Commy it recently went 14.111sec on an unpreped country road (Car Club 1/4 Mile Sprint).
Look at the flow go backwards after the injector boss was squared off. Probably made port to big and affected the port velocity
I disagree.
On a flowbench, velocity (which is a restriction causing an increase in vacuum) is not the best for flow numbers. What changed is how the air enters the port, which had the effect of reducing flow through to the cylinder.
Since I was only measuring a port without an intake manifold, this situation can be changed. I couldn't prove it due to not having access to a manifold.
Alot of the cnc porters leave the injector boss alone. Early heads didn't have injector boss. And apparently flow better om low lift.
Just have a look at the results in your video they are down easy 5% when the boss was removed.
Aftermarket heads have absolutely nothing on these, up to 600-620hp you simply cannot beat a cast VN