Recent content by jnnx

yes, explanation that hydraulic clutch is actually torque converter and the engine is powering the car from (almost) standstill would make lots of sense, and solve this problem.

we know that it reaches 400kmh at 8250rpm with final gear of 2.85:1. from that we can calculate wheel radius of aprox 0.367m thing is, that until 45-50kmh the engine should be disengaged from powering the wheels. so we have only 600Nm of electric motors, and the power output scales with revs...

hi guys did you noticed announcement of new koenigsegg regera? http://jalopnik.com/how-the-1-500-hp-koenigsegg-regera-hits-248-mph-without-1689181377 1500hp, two electric motors driving wheels, and one connected to engine. no transmission, only hydraulic clutch and final drive. interesting...

- with more cylinders you have more friction losses. no way around it. - if I remember old japanese/bmw low volume 6 cyl. engines (2.0-2.5) had bit lower specific torque, but higher specific power output... fuel consumption was always worse than any 4cyl. if I - from lots and lots of engine...

majority of standard production engines idles at 600-800rpm. does not matter if 1.0 four banger or 6.0 v12. I think it is about oil pressure, and bearings construction and load on them

somewhere I have read, that tuners of high performance cars are drilling little holes (like on golf ball) onto intake ducts of cylinder head. it creates turbulent flow near the walls and results in higher flowrate. and they were measuring the results with flowbench so it was not some placebo...

one way how EGR can help fuel consumption is when modern EGR are water cooled. EGR in new cars can recirculate quite large amounts of exhaust fumes and they are cooled by water. so it helps to warm up engine and thus decrease fuel consumption. and some people may think this is not big deal, but...

SteamKing: so weight alone is the only reason? I'm not sure about it. and cummis is probably not ideal comparison. these engines are cast iron, and modern diesel engines are usually made from aluminium (head and block). so there probably wouldn't be that much difference between 3l and 3.5l V6...

modern diesel engines have CR as low as 14:1 (mazda) 15-16 is common... petrol engines go as high as 14:1. also mazda engines...

not really sure about this, but it may be because petrol burns much much faster than diesel. that is why diesel could only rev about 4-5k rpm. petrol burn so fast engines could rev 15'000+ so if diesel burns slowly, the explosion has not much power. petrol will explode much faster and because...

Fuel economy is quite a difficult question. Yes, the engine will probably achieve highest efficiency ( = lowest BSFC) somewhere around revs of highest torque. that is when you are using your fuel most efficiently, but not when you use least of it ! trouble is, that with that load (80-90%) and...

this is thing I'm thinking about for few years. why standard passenger car diesel engines are so limited in engine capacities range? if we take petrol engines, there are anything from 1.0 liter to 3.0l Inline 4 cylinders, 2.0-4.0l 6 cylinders (or even bigger in USA), 4-7l V8 etc. but take...

honestly, if you want engine reving 15k, most likely it would not even IDLE below 1500 rpm... second thing, you want 550hp at 13000rpm. you need 300Nm for that. most engines produce around 100Nm/l so you want the 3.0l V8 ? that really don't sound very low-rpm streetable. cam profiles, intake...

sorry to say that, but I don't think one person can design car from scratch. not what we currently understand as "car". if you find right internet discussion forums you can learn a lot. so read, read, read...

if you want to match 100hp, then you need 100hp. and from what you say, that is almost exactly what you have at 7750rpm. from your dyno graph, you already have that. it is the reduced power map (the red line on graph) just don't rev it over 9000rpmif you want to exactly match the acceleration at...