Porting, can more be done to this?
- Thread starter ruairiyblaster
- Start date
From just looking at the intake there is alot more that can be done to it.Can't say for the rest without pics.The piece in the middle is called the intake bridge.
The bridge can be made a little narrower to match the piston windows, and the flat surface can be ground as you say to a v, or knife edge to split the air.
YES! More can be done to that intake,but remember that its only one piece of a whole. Big intake windows don't make the power,but they do look cool. The exhaust port is where most of the power is made. The larger intake lets the crank case take a bigger gulp of air/fuel mix,but the transfers have to feed it to the cylinder. How do the transfers look? This is why matching the transfer ports to the case is so important. A nice "matched" connection between the transfer ports and case is what your looking for. And......... once all that air/fuel mix is burned in the combustion chamber it has to make an "easy" and fast exit out of the cylinder. How does the exhaust port look? The exhaust port also lets the un-burnt air/fuel mixture,that was drawn into the pipe on "blow down" return just before the piston closes the port. This is why the exhaust port design is so important. That is where the power is made.
It can be, but have you ever looked at an airplane wing?
All the engineering in the world and if it is subsonic, they round the front of the wing.
Only supersonic aircraft get vee'd wing leading edges. Round is better.
Remeber, what ever metal you take off is lowering your primary compression.
Thin it to match the piston bridge, no more.
Steve
A 2s has primary and secondary compression. The actual cylinder is the secondary. Primary is the intake, crank, and all transfer passages. This is the reasoning behind the stuffer blocks on Vitos cranks. The smaller the volume is in primary tract, the higher psi the piston on down stroke before port open can generate. Tho a small volume, it will add up. On a drag motor it's of little concern because lo-mid rpms don't matter, and volumetric eficiency and pipe come more into play.
I am hoping this crude sketch can show the reasons to go rounded rather than sharp on any leading edge port dividers.
If the air flow hits the leading edge at any angle other than perfectly straight on, the sharp divider has flow separation and vorticies that block flow on the leeward lead edge. The rounded edge encourages smooth flow.
The parallel sides of the rounded edge encorage smooth flow into the cylinder. The tapered edges of the wedge create a blockage and make the bridge seem larger than it is to the airflow.
Steve
If the air flow hits the leading edge at any angle other than perfectly straight on, the sharp divider has flow separation and vorticies that block flow on the leeward lead edge. The rounded edge encourages smooth flow.
The parallel sides of the rounded edge encorage smooth flow into the cylinder. The tapered edges of the wedge create a blockage and make the bridge seem larger than it is to the airflow.
Steve
