Recent content by The Chase

  1. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    I would agree with those corrections for sure.
  2. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    If an engine is running 'lean' there is a more abundant amount of oxygen present under combustion than is necessary for a stoichiometric burn, being as compression ignition engines (generally) have a higher presence of oxygen than is needed for a stoichiometric burn (see my results earlier) then...
  3. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    @ Mylarcapsrock Great paper! I've read that one recently, let me quote a few things from it for you; "NOx emissions are associated with high gas temperatures and fuel lean conditions and, in contrast to most other pollutants, are usually observed to increase when biodiesel is used [4]."...
  4. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    If a generalisation, would you not agree it is at least usually true in most situations? Would you also agree it's more accurate than suggesting compression ignition engines cannot run lean at all? I'm unsure what data you would like to see, perhaps you could tell me what data you would like to...
  5. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    Appologies, that was poorly written. I was trying to demonstrate how NO2 production is increased in comparisson to NO production at higher loads due to the more abundant amount of oxygen present when the engine is leaning further. I have a BMEP vs NOx specific results but these are more likely...
  6. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    *Sigh* Yet another test on an older diesel engine with direct injection and no throttle valve. Note how NO and NOx production increases as air to fuel ratio becomes more LEAN. Really, all I have heard so far is how your experience as a technician for 35 years is a far more valid proof than...
  7. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    Traditionally no they don't, modern designs are trending to do so however in order to achieve suitable intake manifold vacuum for EGR operation and to avoid excessive lean out and therefore NO and NOx production at higher loads. Now please, let this lie here and allow the thread to die like...
  8. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    The tests were conducted within an enclosed engine test cell, which includes vast amounts of digital measurement equipment (yes, including digital measurement of intake manifold pressure). I'm not here to get into conflict, only share knowledge with like minded people, if you have data to prove...
  9. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    / Did you check the picture I posted? Clearly, pumping losses are NOT at the most extreme at mid-cruising load, throttle angle is further reduced at zero load under tickover situations, therefore pumping losses are the most extreme here.
  10. T

    Automotive Electric go kart conversion. battery question?

    Glad to be of help, good luck with your project.
  11. T

    Automotive Electric go kart conversion. battery question?

    I'm not too sure why you are using cold cranking amps here. If you are asking 'how long will these batteries power the kart for' then you should be looking for amp-hours. I'm also not too sure where you have this constant of 12.6 but the Watts provided to your circuit should follow basic Ohm's...
  12. T

    Automotive HELP: High Performance Free Flow Exhaust For Single Cylinder (153cc) Engine

    Hello Hertz! Impressive CAD drawing for a first attempt! Helmholtz resonance tuning is what that article is all about, as far as I can tell you're on the right track here but some further reading on Helmholtz theorems certainly won't hurt. Hopefully one of the local geniuses on here will pick...
  13. T

    Automotive Fuel Efficiency: Car #1 vs Car #2 | Ask an Expert

    The answer has been given here already, but as a little addition it is worth noting that VERY low loads can cause poorer specific fuel consumption due to immense pumping losses experienced due to an almost completely closed butterfly valve on the throttle. Though in this example I'm sure this...
  14. T

    Automotive Are Twin Turbos on a 4 Cylinder Engine Worth it for High Performance?

    Twin turbo systems would be classed as an odd choice for a performance small 4 cylinder engine used for automotive use. Twin turbos are (in general) phasing out due to modern turbine development of multi-vane or variable-nozzle turbines which allow for a single turbine to operate over a far...
  15. T

    Automotive Power train calculations question

    I think Chris has answered this for the most part. Remember torque is simply a force across a length, therefore if you have documentation and/or technical papers for the engine you should be able to find out the engines peak torque and at what operational speed it is made at. Assuming peak...
Back
Top