Cam switching is a form of Variable Valve Timing.
Diesel Tuning - Ignition Advance.....
- Thread starter Virdi
- Start date
Cam switching is a form of Variable Valve Timing.
not quite as diesels are naturally lean running, essentially lambda 8. this is far away from a petrol engines necessity of a 14.7:1 (lambda 1) ratio which must always be maintained for clean combustion.
there is always plenty of air as a diesel engine always draws max air regardless (unless egr is in use which can recirculate upto 90% of the air content in modern engines) its fuel that limits power and fuel quantity that controls engine speed.
combustion advance will gain you more upto a point but it has to be set inline with engine load and speed.
sadly you can even bypass the egr anymore as its measured by the maf which will very quiclkly throw you into run home mode.
Which engines measure the EGR by MAF? Mine's blanked and it works a charm - a lot smoother lower down, only downside is it takes a bit longer to warm up on a cold day
mainly newer stuff 01 on depends on what each manufacturer desired, new cars with the tighter euro rules are forced to run with maf monitoring of the egr to stop naughty boys like you and me.
Actually you're right - mine's the Euro 3 but the slightly later Euro 4 ones throw up the EM light if you blank them completely (not limp home though) - you can get around it by putting a small hole in the blanking plate though.
I didn't do mine to get phat powa y0, have you seen the mess they make of the intake?
After 50k miles, there was so much crud in my inlet manifold that there was only about a 0.5cm hole between the main chamber and cylinder 4 port..i have had to chisel out many a inlet manifold over the years due to egr systems.
lets just say that our company loan car runs a now fairly limited egr system.
and for the love of all things holy please no one buy a car with a exhaust particulate filter.
lets just say that our company loan car runs a now fairly limited egr system.
and for the love of all things holy please no one buy a car with a exhaust particulate filter.
Soldato
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Or buy a petrol if you want to go quickly
Diesels are easier tuned, turbo diesels anyway, they're so overbuilt most of the time you can replace the injectors and turbo, give it a map and add a serious amount of power without significant problems.
They also get significant gains from just remaps.
Don't go for a tuning box if you ask me, waste of time and money, a real remap will yield much better, smoother results.
Undoubtedly there's good gains to be had, I'm just saying if I wanted to go fast, I'd buy a petrol car that was fast in the first place 
I'm not anti-diesel, my car's a 2.0 TDCI - plenty power for my needs at the moment, but if I wanted a car for a good hoon I'd just trade it in for an ST220
I'm not anti-diesel, my car's a 2.0 TDCI - plenty power for my needs at the moment, but if I wanted a car for a good hoon I'd just trade it in for an ST220
Soldato
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If I won the lottery I'd buy a load of fast petrol cars, ferraris, lambos, bugattis and all sorts.
But in the current climate my next car is going to be tdi, i love the way they drive, and they're relatively easy engines to work with.
But in the current climate my next car is going to be tdi, i love the way they drive, and they're relatively easy engines to work with.
Same with a diesel, still needs air mixed in, my point was 'In Diesels - The fuel is what gives power' also applies to petrol engines.
Wrong again
less fuel gives more power on a petrol engine as the mixture burns hotter.
Soldato
As I said in the post you quoted; no.
At worst you could over-compress and so some damage, probably crush a bearing.
Wrong again
less fuel gives more power on a petrol engine as the mixture burns hotter.
while lean running does produce more heat it does not give you more power, in fact you can get a substantial torque reduction, theres not much point having a extremely hot point of ignition if there isnt enough fuel to produce a big enough bang to move the piston.
recently went to a technical evening with bosch where they showed their new piezo injector which can pulse inject up to 9 per power stroke*
*or power cycle i should say as pre and post injections now run well into the compression and exhaust stages.
coupled with 2000bar cp3 pumps should make some nice engines.
*or power cycle i should say as pre and post injections now run well into the compression and exhaust stages.
coupled with 2000bar cp3 pumps should make some nice engines.
Soldato
If I have a turbo car running at lambda 0.74 I can make more power by taking away some fuel, usually up to about 0.82 at which point making it leaner will cause excessive heat and lead to melted things
but that's still running 'rich', it has simply been mapped to run a rich mixture to keep the temperatures in the chambers down a bit. so you're not making more power by running it lean, you are making more power by returning it nearer stoich.
Read my original post, I said "LESS FUEL"
Dalin was the one that started using rich and lean comments first.
My original post stands.
Oh and anything above about 0.90 L is classed as lean in 90% of engines whether its still on the "rich" side of stoich or not!
Dalin was the one that started using rich and lean comments first.
My original post stands.
Oh and anything above about 0.90 L is classed as lean in 90% of engines whether its still on the "rich" side of stoich or not!
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Soldato
it doesn't stand.. it's giberish.
taking the statement to the extreme, a petrol engine produces more power using no petrol.
who is it that has classed anything less than 0.90 as lean??
more power is made by more air / higher VE, correct mixture and correct timing.
taking the statement to the extreme, a petrol engine produces more power using no petrol.
who is it that has classed anything less than 0.90 as lean??
more power is made by more air / higher VE, correct mixture and correct timing.
The original post I made was in reply Invader regarding making more power out of a given engine by adding more fuel.
It is correct for diesels, it is incorrect for petrol engines.
Which is what I stated and that is all I stand by.
You can twist the semantics around all you like.
The key here is "correct mixture" as you stated. in 90% of engines that will be 0.90 lambda or richer..
It is correct for diesels, it is incorrect for petrol engines.
Which is what I stated and that is all I stand by.
You can twist the semantics around all you like.
The key here is "correct mixture" as you stated. in 90% of engines that will be 0.90 lambda or richer..