Nice topic, Nigel !Yes of course, it's a very complicated subject.Here is what a very good intake port for a Bullet(by Mondello) looks like, as seen in the Fireball.Viewed from the chamber with the valve outAnd viewed from the other end at the manifold junction, with the valve inYou may notice a few rough or uneven spots remaining, but the aim is to flow best, and we worked with the original casting, and did minimal enlargement. So it was found that removing those areas resulted in poorer flow, so they were not removed. It flowed better with them there, than to smooth them down, because it would have changed the port shape too much, and reduced the desired results.Also, note the concentric rings cut into the valve seat area. This is the most critical flow area, and every one of those angles that are cut, have specifically designed angles to improve the flow. They are not "standard angles". This set of seat angles was developed for this head, and a special seat cutter tool made for Mondello's Serdi valve machine, so that all the angles are machine-cut in a single pass, and are perfectly concentric, and have sharp transitions to effect fuel-shearing for improved atomization of the fuel as it enters the combustion chamber."Wet-flow" technicqus were used in this head design, which takes the wet fuel mixture into account, and not just the air. This can make radical improvements in combustion efficiency, because the fuel is better dispersed into the air, and burns more evenly and efficiently, resulting in better power and economy.This is the rest of the intake system, showing the flow-matched connection of our custom hand-matched alloy manifold to the Mikuni TM32 flat-slide carburetor.You can notice that the flange end of the manifold has holes drilled in it that match the holes drilled into the head, and it is pinned in place, and hand flow-matched to the port entry also. this creates minimum flow disturbance all the way thru the intake tract, and keeps the bulk flow rate even from beginning to end.On the exhaust port with the valve out, you can see a similar treatment for the valve seat area here, and also the special Thermal Barrier ceramic coating inside the exhaust port to minimize heat transfer to the head, which helps prevent overheating of the head from the hot exhaust gases in the port, and speeds up exhaust flow.All of these features are on every Fireball made. It is all standard practice on the Fireballs.These are the kind of things that are needed to bring the power up to the levels that we get. Similar things would need to be done to the UCE, but done specifically for the individual needs of that engine, in order to bring it up to a similar higher power level.
Page created in 0.135 seconds with 32 queries.