Hamilton Cams
ignorant
- Joined
- Jun 28, 2007
- Messages
- 2,639
it is nice to see some discussion on these subjects.
From what I have seen in my time working with diesels. It appears that the advanced timing depending on the rpm, injector, compression ratio etc. , allows more time for the fuel to be burned in the cylinder instead of fuel that is still trying to burn in the exhaust stream.
For people running low compression, the timing has to be advanced even further to get the same peak pressure number at TDC. Of course that is made up at higher boost pressures pulling engines typicall run. This uses a lot of energy and oxygen up prematurely in the cylinder before the piston is at TDC and ready to do some work. Guys running low compression and 40 degrees of timing make things work with mass amounts of air and fuel. I know the same could be done with much less if efficiency was given considerations.
A higher compression piston, in theory would allow you to run less timing(less wasted energy/oxygen before TDC) to get the same peak cylinder pressure. This allows more energy potential for after TDC. A few issues with this school of thought is that you would need a very fast rate of injection to get all of the fuel in the cylinder very soon after TDC since you started later. This is where our new pump cams come in. Another problem is timing that is good for higher rpm would be too much at the lower rpm for drivability, this is where our new 13mm plungers play into the equation. Hopefully after testing is finished, they will allow a few degrees of advancing based on rack travel. One last problem is that cylinder pressures will be phenominal at low rpm/high load. This will require a cam that will bleed off a bit of cylinder pressure at low rpm and gain it back at higher rpm , as the timing starts to advance. If all of this works out this year
I hate the common inefficient engines out there. I hope discussions like these will really help, a new school of thought on building engines. Of course, before now there has never been much options on cams, pistons, heads, stroke length, rod length etc. I really think we are just getting started.
From what I have seen in my time working with diesels. It appears that the advanced timing depending on the rpm, injector, compression ratio etc. , allows more time for the fuel to be burned in the cylinder instead of fuel that is still trying to burn in the exhaust stream.
For people running low compression, the timing has to be advanced even further to get the same peak pressure number at TDC. Of course that is made up at higher boost pressures pulling engines typicall run. This uses a lot of energy and oxygen up prematurely in the cylinder before the piston is at TDC and ready to do some work. Guys running low compression and 40 degrees of timing make things work with mass amounts of air and fuel. I know the same could be done with much less if efficiency was given considerations.
A higher compression piston, in theory would allow you to run less timing(less wasted energy/oxygen before TDC) to get the same peak cylinder pressure. This allows more energy potential for after TDC. A few issues with this school of thought is that you would need a very fast rate of injection to get all of the fuel in the cylinder very soon after TDC since you started later. This is where our new pump cams come in. Another problem is timing that is good for higher rpm would be too much at the lower rpm for drivability, this is where our new 13mm plungers play into the equation. Hopefully after testing is finished, they will allow a few degrees of advancing based on rack travel. One last problem is that cylinder pressures will be phenominal at low rpm/high load. This will require a cam that will bleed off a bit of cylinder pressure at low rpm and gain it back at higher rpm , as the timing starts to advance. If all of this works out this year
I hate the common inefficient engines out there. I hope discussions like these will really help, a new school of thought on building engines. Of course, before now there has never been much options on cams, pistons, heads, stroke length, rod length etc. I really think we are just getting started.
Me likey.