Volumetric efficiency
- Thread starter SammoHung
- Start date
Micra 110
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This might help 
http://en.wikipedia.org/wiki/MA10S#MA10_engine_specifications
whoops...bit big....:laugh: ..ah well at least you can see it! :grinning:
http://en.wikipedia.org/wiki/MA10S#MA10_engine_specificationswhoops...bit big....:laugh: ..ah well at least you can see it! :grinning:
frank
Club Member
sammohung
the ve of a f1 engine is 117%, so with a bit of redesign to your MA with components like these :grinning:
http://picasaweb.google.com/hansderbe/Formula1/photo#5139782620541450482
the ve of a f1 engine is 117%, so with a bit of redesign to your MA with components like these :grinning:
http://picasaweb.google.com/hansderbe/Formula1/photo#5139782620541450482
OP
OP
dude thay IS usefull and quite interesting....much lower than I was guessing at (may be 75% I guessed)....but I'm still digging so I'll come back if nobody elce beats me to it
VE and Torque graphs are not exactly the same. Increasing Volumetric Efficiency will give more power because there is more fuel to burn, however it also increases the temperature of the engine (energy wasted) and so a 10% increase in VE will not achieve a 10% increase in Torque.
Graphs would be a similar shape, depending on the thermal characteristics of the engine, amongst other things, such as friction, engine timing, fuel mixture, perhaps air temperature!
Sammo, the only way to find out the engines VE is to measure the flow rate at the intake, which I don't think anyone will have done before, apart from in the design phases of the engine. So you're looking for some documents that are 20 years old and were probably kept private by Nissan.
So in fact, yes the most accurate way to calculate the VE would be to work backwards from the torque, using some calculation, like Ed says.
The reason I think its probably quite low (65%), is because the engine only has one inlet valve per cylinder.
Graphs would be a similar shape, depending on the thermal characteristics of the engine, amongst other things, such as friction, engine timing, fuel mixture, perhaps air temperature!
Sammo, the only way to find out the engines VE is to measure the flow rate at the intake, which I don't think anyone will have done before, apart from in the design phases of the engine. So you're looking for some documents that are 20 years old and were probably kept private by Nissan.
So in fact, yes the most accurate way to calculate the VE would be to work backwards from the torque, using some calculation, like Ed says.
The reason I think its probably quite low (65%), is because the engine only has one inlet valve per cylinder.
OP
OP
HEHE!
another tenants super strength fuelled exercise….lol
Here’s some MA10 results from a simulator (Engine Analyser Version 3.5 demo version)
I plugged as many facts into this program as I could, but of course I entered some data that was either ‘approximation’ or ‘best educated guess’…lolz (you have to have some fun in life)
Sadly, I couldn’t overlay VE against torque in the graph plotter
The points on the graphs are 1,2,3,4,5 & 6 K rpm only…so the graphs aren’t so smooth
Power & torque
http://www.roadar-northeast.co.uk/K10/stock simulaion BHP Torque.JPG
VE:
http://www.roadar-northeast.co.uk/K10/volumetric efficiency.JPG
But amazingly the fundamentals don’t seem too far away from the book specs…although the absolute levels are lower across the board…
This sort of thing could be useful for predicting the fundamental changes of certain planned mods….
Im goanna have a bash at plugging in the values for my 4-2-1 exhaust and see what the main differences are in the simulation compared with the simulated stock results….
another tenants super strength fuelled exercise….lol
Here’s some MA10 results from a simulator (Engine Analyser Version 3.5 demo version)
I plugged as many facts into this program as I could, but of course I entered some data that was either ‘approximation’ or ‘best educated guess’…lolz (you have to have some fun in life)
Sadly, I couldn’t overlay VE against torque in the graph plotter
The points on the graphs are 1,2,3,4,5 & 6 K rpm only…so the graphs aren’t so smooth
Power & torque
http://www.roadar-northeast.co.uk/K10/stock simulaion BHP Torque.JPG
VE:
http://www.roadar-northeast.co.uk/K10/volumetric efficiency.JPG
But amazingly the fundamentals don’t seem too far away from the book specs…although the absolute levels are lower across the board…
This sort of thing could be useful for predicting the fundamental changes of certain planned mods….
Im goanna have a bash at plugging in the values for my 4-2-1 exhaust and see what the main differences are in the simulation compared with the simulated stock results….
Can I just say that in you trying to be clever there you first disagree with what I say and then agree with me. Its all very well regurgitating what you learnt elsewhere, but in real life keeping things simple is a much better option. Many external factors have very little effect or in fact ones that cannot be measured by any normal person (airflow for instance, which you would then need to divide by engine RPM to produce your graph)
Bottom line is it would be acceptable to use the torque curve to assess what the VE map would look like.
"Sammo, the only way to find out the engines VE is to measure the flow rate at the intake"
You can use other factors such as monitoring the fuel consumption, AF ratios and working backwards to calculate air flow.
One thing that is for sure is that significant torque gains could in theory be produced with the MA10 engine if anyone was to bother. It only produces around 58lbft/litre which is average at best. Its possible to get 2vpc engines to get in excess of 70lb/ft with the correct engine development.
Something of interest: BMEP (break mean effective pressure) something by which you can compare all engiens:
BMEP = 150.8 x TORQUE (lb-ft) / (DISPLACEMENT cc / 16.393)
Stock MA10s = 143 psi (very low)
Stock March ST = 259 psi (very high)
Ill let any interested parties work out the rest. If you get a NA tuned engine above a BMEP of 200, you are doing very very well.
You want to concentrate more on the intake side than the exhaust. Its much harder to get the air into the engine than it is to get it out.
OP
OP
Hells teeth, that sounds like a huge jump...impressive potential
eye, that's where I'm going with this.
I was interested to see if a simulator would be of any usefull assistance by looking at stock and my current setup (stock plus headers)...models to see if the simulated results were anywhere near what would be expected....to kind of get a rough bench-mark.
I ran the sim last night with the headers fitted & it looks like the curves have changed in the right directions (less low to mid torque but slightly higher high RPM power)....the VE got a huge dent at 3000 RPM with the headers fitted...lol
http://www.roadar-northeast.co.uk/K10/Stock plus headers BHP and TORQUE.JPG
http://www.roadar-northeast.co.uk/K10/Stock plus headers VE.JPG
