E92 M3 Engine
- Thread starter Physicist
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centurion
Well-Known Member
Re: E92 M3 Engine
I've never really thought about it - Audi isn't much a competitor to BMW in my book, but this is a natural comparison I guess.
The M3 V8 has borrowed some tech from race tech, like the cracked conrods, and borrowing the individual throttle bodies (instead of Valvetronic) from the older engines. One criticism of the M3's V8 is that it doesn't employ the buzzword direct injection technology, but in fact, it's a high rev engine and being able to already reach 12:1 compression ratio, a big part of DI's advantage - temperature reduction - already not required here. So the disadvantages of DI need not be introduced to this engine, like the reliability and consistency of DI injectors not here yet for 8000rpm engines.
It has a optimal size - 8x500cc - to balance fuel consumption and power generation, but the Audi isn't far off.
But my choice engine is based on something far from technical - the M3's V8 is a screamer, and light as hell, the Audi's is not. Based on these 2 points alone, I would take the M3's V8 as the king. We've a lot of limo engines, praise him who dares to make something closer to a race engine.
I think Shaun is more an authority on thisWelbo;202012 said:
I've never really thought about it - Audi isn't much a competitor to BMW in my book, but this is a natural comparison I guess.
The M3 V8 has borrowed some tech from race tech, like the cracked conrods, and borrowing the individual throttle bodies (instead of Valvetronic) from the older engines. One criticism of the M3's V8 is that it doesn't employ the buzzword direct injection technology, but in fact, it's a high rev engine and being able to already reach 12:1 compression ratio, a big part of DI's advantage - temperature reduction - already not required here. So the disadvantages of DI need not be introduced to this engine, like the reliability and consistency of DI injectors not here yet for 8000rpm engines.
It has a optimal size - 8x500cc - to balance fuel consumption and power generation, but the Audi isn't far off.
But my choice engine is based on something far from technical - the M3's V8 is a screamer, and light as hell, the Audi's is not. Based on these 2 points alone, I would take the M3's V8 as the king. We've a lot of limo engines, praise him who dares to make something closer to a race engine.
centurion
Well-Known Member
Re: E92 M3 Engine
At first I was thinking whether they have some space technology or whatever to achieve 12:1 compression without DI. Then I read that they have the weird thing called Ion Flow ignition. So many complicated explanations, but my one should be simplest:
The coil sends a weak current to the plug, let some ions flow inbetween the plug contents. Voila! This ion flow become like a probe to the engine cylinder to test resistance. Now, it seems that God says that, in his textbook of physics, the higher the density of air inside the cylinder, the higher the resistance.
So in normal operation:
1) Ion flow measures the resistance in the cylinder
2) Once the air density is optimal, the resistance increases, the coil sends an ignition charge igniting the mixture.
In `detonation' situation:
1) Ion flow measures that ... WOW, the increase of resistance is OUT of parameters.
2) sends signal to ECU - Hey, don't send the ignition signal, retard timing, this is gonna blow!
3) Timing retarded, all is safe.
Now this method is MUCH BETTER than the method of putting microphones on the engine to listen to knocks. What an idiotic method that seems like compared to this sweet elegant method.
This wonderful method also means that you can use CRAP 92 fuel and still achieve some optimal fuel economy, at the expense of power generation. Because while the traditional microphone system requires some detonation to actually occur first, this trionic system NEVER has detonation at all because it detects pre-detonation pressure surge, and retards timing before detonation occurs.
This technology is not BMW's tech, it's based on Bosch equipment. Bosch does not own this tech, they licensed it from Saab Trionic, remember? For Saab fans, this sounds familar, right?
Thanks for the question Phil. It makes me able to con some more.
At first I was thinking whether they have some space technology or whatever to achieve 12:1 compression without DI. Then I read that they have the weird thing called Ion Flow ignition. So many complicated explanations, but my one should be simplest:
The coil sends a weak current to the plug, let some ions flow inbetween the plug contents. Voila! This ion flow become like a probe to the engine cylinder to test resistance. Now, it seems that God says that, in his textbook of physics, the higher the density of air inside the cylinder, the higher the resistance.
So in normal operation:
1) Ion flow measures the resistance in the cylinder
2) Once the air density is optimal, the resistance increases, the coil sends an ignition charge igniting the mixture.
In `detonation' situation:
1) Ion flow measures that ... WOW, the increase of resistance is OUT of parameters.
2) sends signal to ECU - Hey, don't send the ignition signal, retard timing, this is gonna blow!
3) Timing retarded, all is safe.
Now this method is MUCH BETTER than the method of putting microphones on the engine to listen to knocks. What an idiotic method that seems like compared to this sweet elegant method.
This wonderful method also means that you can use CRAP 92 fuel and still achieve some optimal fuel economy, at the expense of power generation. Because while the traditional microphone system requires some detonation to actually occur first, this trionic system NEVER has detonation at all because it detects pre-detonation pressure surge, and retards timing before detonation occurs.
This technology is not BMW's tech, it's based on Bosch equipment. Bosch does not own this tech, they licensed it from Saab Trionic, remember? For Saab fans, this sounds familar, right?
Thanks for the question Phil. It makes me able to con some more.
centurion
Well-Known Member
Re: E92 M3 Engine
Phil, take it from my dad, engineer for half a century, spanning from valve>transistor>IC
'Comptuer Electronics is Progress. Progress is NEVER bad. Reliability with the new electronics increased a millionfold. Incredible levels of performance made possible. Now please don't bother me I'm working on this magneto'
Taking from me, who lived his whole young life with crap `classic' cars my dad had:
1) I never had much time with my dad. His head always in the engine bay, front or rear depending on car.
2) He never hugged me - how could he? His hands always were black with grease.
3) My eyes were damaged after staring into a strobe light
4) I thought Lucas was a surname and Fuck was a first name, after all, my dad always threw away boxes with `Lucas' on them and shouted `Fuck Lucas'.
8000rpm with old school rotating distributor = change contact every 200 metresphil;202185 said:
Phil, take it from my dad, engineer for half a century, spanning from valve>transistor>IC
'Comptuer Electronics is Progress. Progress is NEVER bad. Reliability with the new electronics increased a millionfold. Incredible levels of performance made possible. Now please don't bother me I'm working on this magneto'
Taking from me, who lived his whole young life with crap `classic' cars my dad had:
1) I never had much time with my dad. His head always in the engine bay, front or rear depending on car.
2) He never hugged me - how could he? His hands always were black with grease.
3) My eyes were damaged after staring into a strobe light
4) I thought Lucas was a surname and Fuck was a first name, after all, my dad always threw away boxes with `Lucas' on them and shouted `Fuck Lucas'.
phil
Well-Known Member
Re: E92 M3 Engine
hahaha, you are definetly a pom if your dad used Lucas parts, for sure a Vauxhall or similar?
awwwwww, come here big boy, i will give you a hug.
Isnt working on a crap classic car part of the fun, if not the major fun? I'm not talking about those old girls, I was more reminiscing about soem race casr and boats etc. ah yes, blown injected iron big blocks on alcohol. sob sob, better go to the drag boat site for a catch up.
hahaha, you are definetly a pom if your dad used Lucas parts, for sure a Vauxhall or similar?
awwwwww, come here big boy, i will give you a hug.
Isnt working on a crap classic car part of the fun, if not the major fun? I'm not talking about those old girls, I was more reminiscing about soem race casr and boats etc. ah yes, blown injected iron big blocks on alcohol. sob sob, better go to the drag boat site for a catch up.
centurion
Well-Known Member
Re: E92 M3 Engine
Working on cars for 5 hours a weekend is fine, but working on cars EVERY waking hour is ... tiresome ... especially if they break down ALL the time. Valve burned, etc.
my dad had crap british cars, not only Poms buy them, remember? The old empire spanned the world! Lucas was the Bosch of the past!phil;202195 said:
Working on cars for 5 hours a weekend is fine, but working on cars EVERY waking hour is ... tiresome ... especially if they break down ALL the time. Valve burned, etc.
centurion
Well-Known Member
Re: E92 M3 Engine
Their best effort, the S2000 engine has 11.1 compression ratio.
Not bad, but most of Honda's performance indeed comes from precision manufacturing and rpm oriented design - which gives them the ability to rev really high.
rpm rpm and more rpm. Honda has 10.2 compression ratio on the 1.6 170HP SiR.MRacer77;202198 said:
Their best effort, the S2000 engine has 11.1 compression ratio.
Not bad, but most of Honda's performance indeed comes from precision manufacturing and rpm oriented design - which gives them the ability to rev really high.
