Ask those car questions you were always afraid to ask

Même dans les petits moteurs je met de l'ordinaire

Chainsaw
Weed eater
Tondeuse
Tracteur a pelouse
Scie a beton
Compacteur
Generatrice.

A la fin de l'automne je draine tous les reservoirs et je leur met un peu de gaz mix husqvarna ( bon 2-3 ans et 95 octane ) et je les fais virer une couple de secondes.

Sa doit faire 5 ans que je fais ça et je n'ai plus de trouble de carbu.



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Mes coilovers pour mon e36 sont commandé. Est-ce qu'il y a des pièces que je devrais commander ''tant qu'a faire'' ? Le garage m'a parlé de tête de shock qui change presque assurément. Mais je ne comprend pas trop c'est quoi lol est-ce un ''suspension strut mount'' ?
 
jeep22 said:
Même dans les petits moteurs je met de l'ordinaire

Chainsaw
Weed eater
Tondeuse
Tracteur a pelouse
Scie a beton
Compacteur
Generatrice.

A la fin de l'automne je draine tous les reservoirs et je leur met un peu de gaz mix husqvarna ( bon 2-3 ans et 95 octane ) et je les fais virer une couple de secondes.

Sa doit faire 5 ans que je fais ça et je n'ai plus de trouble de carbu.



Sent from my SM-A515W using Tapatalk
Click to expand...

le 10$ la canne de gas premix te coute plus cher que de mettre du super tout le temps et pas avoir a drainer.

meme de l'ordinaire: tu a juste a faire viré avec la valve a gaz a off pour vidé le carbu that's it. si ben stressé tu ajoute un peu de stabilisateur.
Les moteur 2 t rien besoin de faire meme avec de l'ordinaire.

Tes machines vire beaucoup des le debut du printemps...le peu qui peut "gommé" va se cleaner tout seul. (et c'est pas en 5mois qui se gomme grand chose)
 
maxpat82 said:
le 10$ la canne de gas premix te coute plus cher que de mettre du super tout le temps et pas avoir a drainer.

meme de l'ordinaire: tu a juste a faire viré avec la valve a gaz a off pour vidé le carbu that's it. si ben stressé tu ajoute un peu de stabilisateur.
Les moteur 2 t rien besoin de faire meme avec de l'ordinaire.

Tes machines vire beaucoup des le debut du printemps...le peu qui peut "gommé" va se cleaner tout seul. (et c'est pas en 5mois qui se gomme grand chose)
Click to expand...
Sa me coûte 60$ de pre-mix, je full pas les tink.

Les restants de tink que je vide finissent en allume-feu ou dans le beater

Une machine qui fuck au printemps sa coûte beaucoup + que 60$

J'en garde en stock anyway parce que en pleine canicule les trimmer a haie, chainsaw, scie a beton ont de la misère. ( le gaz ordinaire bouille dans la tink)

Pour la paix d'esprit sa ne coûte pas cher.


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Snail said:
I read a piece on the E46 M3 CSL, which has a 3.2L L6 (S54) and it doesn't use a mass airflow sensor, which according to the article makes for a quicker throttle response. Instead, air flow is calculated "directly by the DME" (ECU - disney's magical experience).

What is the trade-off? ie, if you get better throttle response, but no one else is doing it, why? Also the E46 is 20 years old now, I'll assume tricks that worked back then can't work today because of emissions regulations. Should I assume this be the case? I find today's "mainstream car engines" have diesel-like throttle response due to combustion control and limiting the amount of fuel that gets sent in to improve lean burning. Could you run without a MAF in today's engines? Would it change absolutely nothing? (I'm gonna guess likely)
Click to expand...

It's how most performance cars were calibrated back then.

With a MAF the logic goes: measure the air coming in with the MAF, check throttle opening, check the engine's RPM, calculate and inject amount of fuel for the measured amount of air coming in.

The CSL or a lot of N/A cars are calibrated with Alpha-N method: i.e. For a set RPM and throttle opening it injects a set amount of fuel, there's no calculation. It's just a lookup table of throttle opening and RPM that gives a set value of ignition timing and fuel for that RPM and throttle opening. It's essentialy just a lookup table with some mofifyers for ambient air temp, air pressure, etc, so there's no calculation involved, hence it's more responsive if you have limited computing power.

Modern cars are mapped on a torque request. The torque request is the throttle pedal (0-100%), then the ECU calculates how much boost, ignition, throttle opening you need to achieve that torque at this specific RPM. So 100% throttle pedal is not necessarily 100% boost, or maximum ignition, or 100% throttle opening at the engine. it's just a combinaison of those factors to give you the best torque in the most efficient way. The delays in throttle ''rev hang'' are for emissions to burn fuel that would be unburnt in sudden changes of throttle or RPM, and also for vibration and harshness.

Fun fact: even with 100% throttle pedal, some cars run at part throttle body opening to put load on the turbo to be in a more efficient zone.
 
oldschoolZ said:
It's how most performance cars were calibrated back then.

With a MAF the logic goes: measure the air coming in with the MAF, check throttle opening, check the engine's RPM, calculate and inject amount of fuel for the measured amount of air coming in.

The CSL or a lot of N/A cars are calibrated with Alpha-N method: i.e. For a set RPM and throttle opening it injects a set amount of fuel, there's no calculation. It's just a lookup table of throttle opening and RPM that gives a set value of ignition timing and fuel for that RPM and throttle opening. It's essentialy just a lookup table with some mofifyers for ambient air temp, air pressure, etc, so there's no calculation involved, hence it's more responsive if you have limited computing power.

Modern cars are mapped on a torque request. The torque request is the throttle pedal (0-100%), then the ECU calculates how much boost, ignition, throttle opening you need to achieve that torque at this specific RPM. So 100% throttle pedal is not necessarily 100% boost, or maximum ignition, or 100% throttle opening at the engine. it's just a combinaison of those factors to give you the best torque in the most efficient way. The delays in throttle ''rev hang'' are for emissions to burn fuel that would be unburnt in sudden changes of throttle or RPM, and also for vibration and harshness.

Fun fact: even with 100% throttle pedal, some cars run at part throttle body opening to put load on the turbo to be in a more efficient zone.
Click to expand...

very cool, thanks for the response! so if I take, for example another higher-performance naturally aspirated engine of that era, why would the manufacturer choose to calculated air flow with a sensor as opposed to a table of presets? more accurate I suppose (so cleaner and more power) but with a little more lag?
 
Snail said:
very cool, thanks for the response! so if I take, for example another higher-performance naturally aspirated engine of that era, why would the manufacturer choose to calculated air flow with a sensor as opposed to a table of presets? more accurate I suppose (so cleaner and more power) but with a little more lag?
Click to expand...

IIRC, the E46 M3 use an ITB system, which means a "traditional" MAF setup is harder to use.
 
Snail said:
very cool, thanks for the response! so if I take, for example another higher-performance naturally aspirated engine of that era, why would the manufacturer choose to calculated air flow with a sensor as opposed to a table of presets? more accurate I suppose (so cleaner and more power) but with a little more lag?
Click to expand...

More accurate, better for emissions, cleaner running since it's a ''closed loop'' system with constant feedback. For an ecu with a set lookup table you need to have a very good lookup table for every RPM and every throttle opening, the smaller the RPM and throttle steps in the lookup, the better the resolution.
 
IIRC only reason MAF was being used on MS S54 was for emissions, especially cold start. CSL had a completely different management system with a shit ton more tables built in. MS S54 achieves 100% efficiency at 95% open throttle

FYI all MAF cars have default tables built in for when and if the maf fails.
 
oldschoolZ said:
It's how most performance cars were calibrated back then.

With a MAF the logic goes: measure the air coming in with the MAF, check throttle opening, check the engine's RPM, calculate and inject amount of fuel for the measured amount of air coming in.

The CSL or a lot of N/A cars are calibrated with Alpha-N method: i.e. For a set RPM and throttle opening it injects a set amount of fuel, there's no calculation. It's just a lookup table of throttle opening and RPM that gives a set value of ignition timing and fuel for that RPM and throttle opening. It's essentialy just a lookup table with some mofifyers for ambient air temp, air pressure, etc, so there's no calculation involved, hence it's more responsive if you have limited computing power.

Modern cars are mapped on a torque request. The torque request is the throttle pedal (0-100%), then the ECU calculates how much boost, ignition, throttle opening you need to achieve that torque at this specific RPM. So 100% throttle pedal is not necessarily 100% boost, or maximum ignition, or 100% throttle opening at the engine. it's just a combinaison of those factors to give you the best torque in the most efficient way. The delays in throttle ''rev hang'' are for emissions to burn fuel that would be unburnt in sudden changes of throttle or RPM, and also for vibration and harshness.

Fun fact: even with 100% throttle pedal, some cars run at part throttle body opening to put load on the turbo to be in a more efficient zone.
Click to expand...


I can't say I've seen a lot of Alpha-N tuned production cars... usually see Speed Density if there isn't a MAF sensor.

I usually only see alpha-N used on race motors that don't pull any vacuum due to the camshaft.
 
Probably a good fancy ECU could blend the best attributes of two airflow estimation schemes for the best overall result:
Good long-term accuracy, but slow response: MAF
Fast response, but low long-term accuracy: speed-density / alpha-n

My MegaSquirt has a 2D RPM/TPS->MAP lookup table, so if the MAP sensor is considered to have died, it can switch to an estimated MAP value. The car basically becomes alpha-n at that point. It works enough to limp home.

Nowadays, there's no need to track and attempt to follow rapid driver-induced airflow changes, since the ECU is running the show...


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Torque request represents the numbing, isolation, and needless complexity of modern cars.

I want throttle angle = pedal position, that's it, not an abstraction layer between myself and reality. As such, DBW gives me zero benefits over cable throttle.
 
pmbrunelle said:
Probably a good fancy ECU could blend the best attributes of two airflow estimation schemes for the best overall result:
Good long-term accuracy, but slow response: MAF
Fast response, but low long-term accuracy: speed-density / alpha-n

My MegaSquirt has a 2D RPM/TPS->MAP lookup table, so if the MAP sensor is considered to have died, it can switch to an estimated MAP value. The car basically becomes alpha-n at that point. It works enough to limp home.

Nowadays, there's no need to track and attempt to follow rapid driver-induced airflow changes, since the ECU is running the show...


********************************************************************************

Torque request represents the numbing, isolation, and needless complexity of modern cars.

I want throttle angle = pedal position, that's it, not an abstraction layer between myself and reality. As such, DBW gives me zero benefits over cable throttle.
Click to expand...

Maybe for a 1995 car, but modern cars with DBW are much better, you can change the pedal map / response to suit different conditions (wet, low grip, high grip, etc.), ''sport mode'' on most cars is just the sensitivity of the torque request (pedal), there's no actual engine map change.

Torque request is the way to go, on modern cars with DCT (Porsche GT3 with PDK, M3 and such), it's the torque request from the pedal that drives the gearbox controller, which then tells the ECU what to do and not the other way around. You always get the best torque for that specific RPM. For example, throttles closing to load the turbo slightly for better response, etc.
 
I started driving in 2006, so growing up with 10-year old used cars, I began driving with stuff from around the 1995 model year era.

The tech/complexity level of cars back then met my needs at the time. Nothing has changed between then and now that I would require (or desire) more tech in my transportation.
 
Yea until you start driving modern cars more often and how they do everything so damn well. Ive always thought the ones against any tech change or wishing for the old days just don't understand how modern systems work

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I understand how the modern stuff works... in my day job I work on the design of electric power steering, and I briefly worked on an automated manual trans.

Understanding how modern stuff works is different from feeling that it brings benefits worth having.

I still attempt to live the "old days".
Toy: 1985 Pontiac Fiero, 3.2 turbo, cable throttle, no cruise, roll-up windows, manual trans, no AC, no ABS, no power steering
Daily: 2007 Ford Ranger, 3.0, cable throttle, no cruise, roll-up windows, manual trans, with AC, with ABS, with hydraulic power steering

I've been forced to drive newer cars for work (rental cars for trips), and I thought they were terrible, but maybe that's because they were rental cars.
 
Even if technology progressed.. a solid manual car still checks the box for me. Don t care about gas consumption, rattle in exhaust and other crap.
Guve me raw power till resline and let me shift. I can do the thinking as i please
 
Are there any gasoline cars that have electric heating? It would be such a simple thing to implement and so useful during winter.
It would push hot air in seconds instead of waiting for coolant to heat up.
Ideas?
 
You might need 1000 W or so of electrical power for a decent heater. On a 12 V electrical system, that's an extra 83 A, on perhaps a 150 A alternator.

So you would need to spend a lot of money to upsize the alternator (and making sure the serpentine belt drive is up to the task), for pretty much the irrelevant Canadian market which will buy your car anyway without the heater.

Also, right after startup, the alternator is busy recharging the battery, so having those two heavy loads at the same time is going to be rough for the alternator.

The heat liberated by burning fuel in a normal car engine goes to three places, approximately like this:
1/3 power to the crankshaft
1/3 heat out the exhaust pipe
1/3 heat dumped into the coolant, then out through the radiator (or heater core)

The heat from the coolant is "free" and needs to lost anyway (if not through the heater core, the main radiator), so that's why it's used.

In principle, I don't see why an electric heater couldn't be implemented, it just seems like a huge waste of money for a small market.
 
Plumb exhaust line into the cabin and recycle the lost 1/3.
Problem solved.

(Problem solved as in the driver is gonna fall asleep and slowly die, so no need to warm him up anymore)
 
I think 1000w is a lot. Probably 300w would be sufficient. I keep thinking of a 300w incandescent bulb that radiates lots of heat.
if the option would be available i would select it and pay extra.
Hell i have heated steering wheel and i would ve loved a heated shifter 😀
 
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