F/I strains engine?
06-15-2016, 11:35 AM
#41
Registered User
Thread Starter
06-15-2016, 11:37 AM
#42
Registered User
Thread Starter
FI engine will make relatively the same power even as altitude changes. The altitude means the pressure outside is less...14.7psi at sea level i believe. Thats why NA are dogs in the mountains since less pressure outside to push air into the cylinders.
(while out of boost the FI engine will be down a bit on power as well)
(while out of boost the FI engine will be down a bit on power as well)
06-15-2016, 11:39 AM
#43
No. But there will be increased pressure in the cylinders, and increased force from the higher combustion energy released by the denser cylinder charge. This results in more force on the pistons, rods, bearings, crank, etc. That's the point of FI - more energy released in the same displacement - so the engine "feels" larger than it is.
06-15-2016, 11:43 AM
#44
Registered User
Thread Starter
No. But there will be increased pressure in the cylinders, and increased force from the higher combustion energy released by the denser cylinder charge. This results in more force on the pistons, rods, bearings, crank, etc. That's the point of FI - more energy released in the same displacement - so the engine "feels" larger than it is.
If the NA and FI theoretically has the same amount of air molecules, does the FI see a bigger increase in cylinder pressure?
06-15-2016, 11:49 AM
#46
The point of FI is to force more air and fuel into the cylinder without increasing the size of the cylinder. More fuel and air = more energy released during combustion = more power. The air/fuel ratio still has to be about the same, so there's more of both in an FI engine. You could do the same thing in an NA engine by making the cylinders larger.
Imagine if your car always lived on Mt. Everest, and was designed to run at that altitude. Now you drive it down to sea level, and the air is much denser. Assuming the injectors could pump in enough fuel, it would feel like your engine now had FI.
Imagine if your car always lived on Mt. Everest, and was designed to run at that altitude. Now you drive it down to sea level, and the air is much denser. Assuming the injectors could pump in enough fuel, it would feel like your engine now had FI.
06-15-2016, 11:53 AM
#47
This is basic chemistry. P1 x V1/T1 = P2 x V2/T2. That's why you need an intercooler, because the compressed charge has more molecules, holding more heat. BTW, that's also how refrigeration (A/C) works.
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CK_32 (06-15-2016)
06-15-2016, 11:57 AM
#48
Registered User
Thread Starter
THEY DON'T. The FI engine has more molecules of air, because a larger volume of atmospheric air is compressed to fit into the same volume of the cylinders.
This is basic chemistry. P1 x V1/T1 = P2 x V2/T2. That's why you need an intercooler, because the compressed charge has more molecules, holding more heat. BTW, that's also how refrigeration (A/C) works.
This is basic chemistry. P1 x V1/T1 = P2 x V2/T2. That's why you need an intercooler, because the compressed charge has more molecules, holding more heat. BTW, that's also how refrigeration (A/C) works.
06-15-2016, 03:45 PM
#51
Registered User
Thread Starter
But my main question was exactly how can a boosted car be more stressed than an NA if everything else is identical.
06-15-2016, 05:20 PM
#52
350Z/370Z Tech Moderator
MY350Z.COM
MY350Z.COM
I find this a VERY interesting topic because of my own experiences with turbocharging, both from a factory and an aftermarket standpoint. FTR, I've owned something like 8-10 turbo cars, two built with aftermarket components and the rest factory FI cars - including two in my stable currently.
So here's my as-close-to-a-Reader's-Digest-style assessment as I can make it. (But it's still way lonnnnnnng as this is a complex topic.) - You are warned.
________________________________________
Number one, fact versus fallacy:
Wear and tear between a 400bhp normally aspirated engine and a 400bhp forced induction engine are NOT the same. Fact.
Start by examining the basic principles of a normally aspirated engine:
An NA engine producing that much power relies on many components but the one area that is primarily being discussed here is how said engine gets it's air in and out of the engine - how it "breathes" as it were.
NA relies on a number of different-from-FI aspects: compression ratio, valve sizing, intake path design, cylinder size/volume, camshaft lift and duration, combustion chamber size, and overall displacement. And so on.... The bottom line here is that it relies on the engines "natural breathing" (no external help) to move air in and out.
Like an olympic runner or swimmer, big, highly conditioned lungs can move air in/out more effectively and efficiently than "mere mortals". So, to bring out more efficiency and effectiveness (mo' power) from your engine, increasing the size, design, specifications, of any of the above mentioned components can yield higher breathing capabilities. (Should be noted that a properly designed combination of all of the above are required to make the most effective changes throughout the engine's operating cycle.)
In order for a NA engine to take in an amount of air equal to what a turbo or supercharger does - to keep things "equal", it would require increases in all of the above.
So, the initial question of "How does the engine know if the air is sucked in by piston action or if it's mechanically forced in?" is actually a very astute question.
With a simple answer...
It doesn't.
However....
The NA engine, due to its generally more sizable displacement and upsized/tuned components will generally have a lower specific output (the engine size to power ratio; say, "one hp per cubic inch" or "82 hp per liter") than a forced induction engine.
But it is also designed to not exceed it's physical limitations. And, any changes to any of the components referenced merely help it breath better ON IT'S OWN and NOT with the use of an external charge mechanism.
In other words, the NA engine does not, can not exceed it's own natural breathing limitations. Hence, the engine works under a "designed stress load" - generally speaking at a much lower or tempermental level than an FI motor. Not to say it can't break, of course it can; but not to the type and extent of damage generally, of a forced induction engine. Read on....
________________________________________
Now, let's examine what happens when you put a blower on an engine.
But we need to confirm another thing (myth or fact) first:
Turbocharging and Supercharging (forced induction) both induce more stresses on an engine than a like-for-like (powered) normally aspirated engine. We can all agree on that.
But why?
1. Heat
2. Pressure
3. Components and algorithms not designed to handle #1 and #2.
That's pretty much it.
T'bo, you likened the engine to an air pump. That's essentially true. More in, more out.
But an engine, like any pump, is a mechanical device and as anyone knows (and Dean likened this to a weightlifter in his excellent example earlier), you push said device - be it an engine or a human) past its physical limits and stuff is going to break.
Let's examine what can go funky in a blown engine:
Gaskets - rudimentary, right?
Let's use head gaskets, amongst the many, as an example. They're there to seal the surfaces between the heads and the block and keep stuff that needs to be inside on the inside. What happens when you add pressure (due to a higher concentration of air/fuel resulting in a larger explosion inside the cylinder).
You exert many times the pressure it may have been designed for. Simple, obvious result: blown head gasket - which can lead to every kind of failure known to an internal combustion engine....cooling failure, oil starvation from loss of oil pressure, combustion gasses blowing out the side of the motor, etc.
I don't think I need to expand on the resulting mechanical chaos in the event of oil starvation or overheating do I?
Valvetrain stress - every component of the valve train has to work harder to maintain valve sealing AND there's even more undue stress on the cam(s), followers, springs, etc. in opening and closing of the valves going against the increased cylinder pressures.
In a heavy boost, high rpm incidence, valves may start to float, springs get overworked trying to keep the valves closed, opening them becomes a chore and strain on the cam actuators and this can lead to premature failure of the cam - and any of cam followers componentry.
Cylinder wall, piston, damage- Think of these items as if they were balloons. Fill them with something - water, air, or in this case a very dense air/fuel mix leading to higher cylinder pressures upon ignition, well, it's plain to see that these items (and all surrounding components) may suffer a similar fate as the balloon. They can stress and ultimately crack or break if forced to work beyond their design.
As David (dkmura) pointed out earlier, the VG series engines in the Z32 (and other non-US-spec cars) are built much more stout being designed specifically for forced induction (times two). How? Through thicker cylinder walls, more internal block webbing, better main bearing caps, stronger bearings. And perhaps, no, make that for sure, the biggest difference, the construction material of the block itself, cast iron (VG) versus aluminum (VQ).
While aluminum is lighter and very strong, it doesn't have the heat resistance properties that cast iron does and to make an aluminum block last as long as cast iron in an FI application, the addition of iron sleeve liners are sometimes recommended to resist the higher heat generated within the cylinder.
Note: This is NOT saying aluminum is unsuitable for FI applications at all. However, contemporary all-aluminum engines that are designed to be turbocharged are engineered from the design phase through production with higher grade aluminum, different sizing and densities, and in general, designed to withstand turbo/supercharged applications.
Saved the "best" for last.... THE biggest enemy of an FI engine (any engine actually but many fold worse in an FI engine) and perhaps the most highly overlooked when building a forced induction engine is DETONATION.
This can come from many things; but the two biggest culprits are:
- Insufficient fuel to properly match the incoming pressurized air charge ("lean out" or, slightly more scientifically, the stoichiometric A/F mix is askew... higher than 14.7:1) and...
- Insufficient or mistimed spark.
So you have this engine that is now receiving a super dense air entering the engine thanks to the air-charger(s). The resulting what-ifs that can lead to premature failure or outright destruction:
- What if the spark isn't hot enough to ignite it properly and fully?
- What if said spark occurs during the wrong portion of the combustion cycle, e.g., too early, too late?
- What if there's more air than fuel? (Meaning, the builder hasn't upsized the volume of fuel delivery or it's not functioning properly.... higher capacity pump, larger injectors.)
Disaster happens.
Any/all of these lead to detonation, which, I don't need to tell anyone who's taken Auto Shop 101, is deadly and will likely cause massive engine failure from these mini-hand-grenades going off in rapid sequence internally if left unchecked.
To properly prevent this, ALL of the mechanical ignition components (coilpacks, wiring, distributor/magneto (in such applications), plugs, etc.) ALL need to be upgraded to match the new parameters the engine is forced (no pun intended) to run under.
Generally speaking, when factories design their cars with factory turbo engines, you can bet these components are all upgraded (and often carried "down" to their normally aspirated brethren to cut overall costs by keeping the components consistent) before testing.
AND, more importantly, in addition to the hardware, the brain mapping (ECU parameters) - the software side - is all different. Timing curves (advance and retard points - and all facets of spark control) need to be mated to all of the engine's new different-from-stock operating conditions: boost pressure, engine speed, fuel pressure, MAF readings, knock sensor(s), O2 readings, all happening simultaneously to interpret and maintain what's going on inside the engine.
--------------------------------------
I could go on and on and on but this is a cursory look at why a turbo or supercharged engine - especially one done after the fact like any/all aftermarket systems - are more stressful to an engine.
Hope this helps to answer the question, T'bo (and any other interested parties).
The following 3 users liked this post by MicVelo:
06-15-2016, 07:02 PM
#54
Registered User
Thread Starter
Well, the main point here is that everything is NOT equal between the two so I'll weigh in here.
I find this a VERY interesting topic because of my own experiences with turbocharging, both from a factory and an aftermarket standpoint. FTR, I've owned something like 8-10 turbo cars, two built with aftermarket components and the rest factory FI cars - including two in my stable currently.
So here's my as-close-to-a-Reader's-Digest-style assessment as I can make it. (But it's still way lonnnnnnng as this is a complex topic.) - You are warned.
________________________________________
Number one, fact versus fallacy:
Wear and tear between a 400bhp normally aspirated engine and a 400bhp forced induction engine are NOT the same. Fact.
Start by examining the basic principles of a normally aspirated engine:
An NA engine producing that much power relies on many components but the one area that is primarily being discussed here is how said engine gets it's air in and out of the engine - how it "breathes" as it were.
NA relies on a number of different-from-FI aspects: compression ratio, valve sizing, intake path design, cylinder size/volume, camshaft lift and duration, combustion chamber size, and overall displacement. And so on.... The bottom line here is that it relies on the engines "natural breathing" (no external help) to move air in and out.
Like an olympic runner or swimmer, big, highly conditioned lungs can move air in/out more effectively and efficiently than "mere mortals". So, to bring out more efficiency and effectiveness (mo' power) from your engine, increasing the size, design, specifications, of any of the above mentioned components can yield higher breathing capabilities. (Should be noted that a properly designed combination of all of the above are required to make the most effective changes throughout the engine's operating cycle.)
In order for a NA engine to take in an amount of air equal to what a turbo or supercharger does - to keep things "equal", it would require increases in all of the above.
So, the initial question of "How does the engine know if the air is sucked in by piston action or if it's mechanically forced in?" is actually a very astute question.
With a simple answer...
It doesn't.
However....
The NA engine, due to its generally more sizable displacement and upsized/tuned components will generally have a lower specific output (the engine size to power ratio; say, "one hp per cubic inch" or "82 hp per liter") than a forced induction engine.
But it is also designed to not exceed it's physical limitations. And, any changes to any of the components referenced merely help it breath better ON IT'S OWN and NOT with the use of an external charge mechanism.
In other words, the NA engine does not, can not exceed it's own natural breathing limitations. Hence, the engine works under a "designed stress load" - generally speaking at a much lower or tempermental level than an FI motor. Not to say it can't break, of course it can; but not to the type and extent of damage generally, of a forced induction engine. Read on....
________________________________________
Now, let's examine what happens when you put a blower on an engine.
But we need to confirm another thing (myth or fact) first:
Turbocharging and Supercharging (forced induction) both induce more stresses on an engine than a like-for-like (powered) normally aspirated engine. We can all agree on that.
But why?
1. Heat
2. Pressure
3. Components and algorithms not designed to handle #1 and #2.
That's pretty much it.
T'bo, you likened the engine to an air pump. That's essentially true. More in, more out.
But an engine, like any pump, is a mechanical device and as anyone knows (and Dean likened this to a weightlifter in his excellent example earlier), you push said device - be it an engine or a human) past its physical limits and stuff is going to break.
Let's examine what can go funky in a blown engine:
Gaskets - rudimentary, right?
Let's use head gaskets, amongst the many, as an example. They're there to seal the surfaces between the heads and the block and keep stuff that needs to be inside on the inside. What happens when you add pressure (due to a higher concentration of air/fuel resulting in a larger explosion inside the cylinder).
You exert many times the pressure it may have been designed for. Simple, obvious result: blown head gasket - which can lead to every kind of failure known to an internal combustion engine....cooling failure, oil starvation from loss of oil pressure, combustion gasses blowing out the side of the motor, etc.
I don't think I need to expand on the resulting mechanical chaos in the event of oil starvation or overheating do I?
Valvetrain stress - every component of the valve train has to work harder to maintain valve sealing AND there's even more undue stress on the cam(s), followers, springs, etc. in opening and closing of the valves going against the increased cylinder pressures.
In a heavy boost, high rpm incidence, valves may start to float, springs get overworked trying to keep the valves closed, opening them becomes a chore and strain on the cam actuators and this can lead to premature failure of the cam - and any of cam followers componentry.
Cylinder wall, piston, damage- Think of these items as if they were balloons. Fill them with something - water, air, or in this case a very dense air/fuel mix leading to higher cylinder pressures upon ignition, well, it's plain to see that these items (and all surrounding components) may suffer a similar fate as the balloon. They can stress and ultimately crack or break if forced to work beyond their design.
As David (dkmura) pointed out earlier, the VG series engines in the Z32 (and other non-US-spec cars) are built much more stout being designed specifically for forced induction (times two). How? Through thicker cylinder walls, more internal block webbing, better main bearing caps, stronger bearings. And perhaps, no, make that for sure, the biggest difference, the construction material of the block itself, cast iron (VG) versus aluminum (VQ).
While aluminum is lighter and very strong, it doesn't have the heat resistance properties that cast iron does and to make an aluminum block last as long as cast iron in an FI application, the addition of iron sleeve liners are sometimes recommended to resist the higher heat generated within the cylinder.
Note: This is NOT saying aluminum is unsuitable for FI applications at all. However, contemporary all-aluminum engines that are designed to be turbocharged are engineered from the design phase through production with higher grade aluminum, different sizing and densities, and in general, designed to withstand turbo/supercharged applications.
Saved the "best" for last.... THE biggest enemy of an FI engine (any engine actually but many fold worse in an FI engine) and perhaps the most highly overlooked when building a forced induction engine is DETONATION.
This can come from many things; but the two biggest culprits are:
- Insufficient fuel to properly match the incoming pressurized air charge ("lean out" or, slightly more scientifically, the stoichiometric A/F mix is askew... higher than 14.7:1) and...
- Insufficient or mistimed spark.
So you have this engine that is now receiving a super dense air entering the engine thanks to the air-charger(s). The resulting what-ifs that can lead to premature failure or outright destruction:
- What if the spark isn't hot enough to ignite it properly and fully?
- What if said spark occurs during the wrong portion of the combustion cycle, e.g., too early, too late?
- What if there's more air than fuel? (Meaning, the builder hasn't upsized the volume of fuel delivery or it's not functioning properly.... higher capacity pump, larger injectors.)
Disaster happens.
Any/all of these lead to detonation, which, I don't need to tell anyone who's taken Auto Shop 101, is deadly and will likely cause massive engine failure from these mini-hand-grenades going off in rapid sequence internally if left unchecked.
To properly prevent this, ALL of the mechanical ignition components (coilpacks, wiring, distributor/magneto (in such applications), plugs, etc.) ALL need to be upgraded to match the new parameters the engine is forced (no pun intended) to run under.
Generally speaking, when factories design their cars with factory turbo engines, you can bet these components are all upgraded (and often carried "down" to their normally aspirated brethren to cut overall costs by keeping the components consistent) before testing.
AND, more importantly, in addition to the hardware, the brain mapping (ECU parameters) - the software side - is all different. Timing curves (advance and retard points - and all facets of spark control) need to be mated to all of the engine's new different-from-stock operating conditions: boost pressure, engine speed, fuel pressure, MAF readings, knock sensor(s), O2 readings, all happening simultaneously to interpret and maintain what's going on inside the engine.
--------------------------------------
I could go on and on and on but this is a cursory look at why a turbo or supercharged engine - especially one done after the fact like any/all aftermarket systems - are more stressful to an engine.
Hope this helps to answer the question, T'bo (and any other interested parties).
I find this a VERY interesting topic because of my own experiences with turbocharging, both from a factory and an aftermarket standpoint. FTR, I've owned something like 8-10 turbo cars, two built with aftermarket components and the rest factory FI cars - including two in my stable currently.
So here's my as-close-to-a-Reader's-Digest-style assessment as I can make it. (But it's still way lonnnnnnng as this is a complex topic.) - You are warned.
________________________________________
Number one, fact versus fallacy:
Wear and tear between a 400bhp normally aspirated engine and a 400bhp forced induction engine are NOT the same. Fact.
Start by examining the basic principles of a normally aspirated engine:
An NA engine producing that much power relies on many components but the one area that is primarily being discussed here is how said engine gets it's air in and out of the engine - how it "breathes" as it were.
NA relies on a number of different-from-FI aspects: compression ratio, valve sizing, intake path design, cylinder size/volume, camshaft lift and duration, combustion chamber size, and overall displacement. And so on.... The bottom line here is that it relies on the engines "natural breathing" (no external help) to move air in and out.
Like an olympic runner or swimmer, big, highly conditioned lungs can move air in/out more effectively and efficiently than "mere mortals". So, to bring out more efficiency and effectiveness (mo' power) from your engine, increasing the size, design, specifications, of any of the above mentioned components can yield higher breathing capabilities. (Should be noted that a properly designed combination of all of the above are required to make the most effective changes throughout the engine's operating cycle.)
In order for a NA engine to take in an amount of air equal to what a turbo or supercharger does - to keep things "equal", it would require increases in all of the above.
So, the initial question of "How does the engine know if the air is sucked in by piston action or if it's mechanically forced in?" is actually a very astute question.
With a simple answer...
It doesn't.
However....
The NA engine, due to its generally more sizable displacement and upsized/tuned components will generally have a lower specific output (the engine size to power ratio; say, "one hp per cubic inch" or "82 hp per liter") than a forced induction engine.
But it is also designed to not exceed it's physical limitations. And, any changes to any of the components referenced merely help it breath better ON IT'S OWN and NOT with the use of an external charge mechanism.
In other words, the NA engine does not, can not exceed it's own natural breathing limitations. Hence, the engine works under a "designed stress load" - generally speaking at a much lower or tempermental level than an FI motor. Not to say it can't break, of course it can; but not to the type and extent of damage generally, of a forced induction engine. Read on....
________________________________________
Now, let's examine what happens when you put a blower on an engine.
But we need to confirm another thing (myth or fact) first:
Turbocharging and Supercharging (forced induction) both induce more stresses on an engine than a like-for-like (powered) normally aspirated engine. We can all agree on that.
But why?
1. Heat
2. Pressure
3. Components and algorithms not designed to handle #1 and #2.
That's pretty much it.
T'bo, you likened the engine to an air pump. That's essentially true. More in, more out.
But an engine, like any pump, is a mechanical device and as anyone knows (and Dean likened this to a weightlifter in his excellent example earlier), you push said device - be it an engine or a human) past its physical limits and stuff is going to break.
Let's examine what can go funky in a blown engine:
Gaskets - rudimentary, right?
Let's use head gaskets, amongst the many, as an example. They're there to seal the surfaces between the heads and the block and keep stuff that needs to be inside on the inside. What happens when you add pressure (due to a higher concentration of air/fuel resulting in a larger explosion inside the cylinder).
You exert many times the pressure it may have been designed for. Simple, obvious result: blown head gasket - which can lead to every kind of failure known to an internal combustion engine....cooling failure, oil starvation from loss of oil pressure, combustion gasses blowing out the side of the motor, etc.
I don't think I need to expand on the resulting mechanical chaos in the event of oil starvation or overheating do I?
Valvetrain stress - every component of the valve train has to work harder to maintain valve sealing AND there's even more undue stress on the cam(s), followers, springs, etc. in opening and closing of the valves going against the increased cylinder pressures.
In a heavy boost, high rpm incidence, valves may start to float, springs get overworked trying to keep the valves closed, opening them becomes a chore and strain on the cam actuators and this can lead to premature failure of the cam - and any of cam followers componentry.
Cylinder wall, piston, damage- Think of these items as if they were balloons. Fill them with something - water, air, or in this case a very dense air/fuel mix leading to higher cylinder pressures upon ignition, well, it's plain to see that these items (and all surrounding components) may suffer a similar fate as the balloon. They can stress and ultimately crack or break if forced to work beyond their design.
As David (dkmura) pointed out earlier, the VG series engines in the Z32 (and other non-US-spec cars) are built much more stout being designed specifically for forced induction (times two). How? Through thicker cylinder walls, more internal block webbing, better main bearing caps, stronger bearings. And perhaps, no, make that for sure, the biggest difference, the construction material of the block itself, cast iron (VG) versus aluminum (VQ).
While aluminum is lighter and very strong, it doesn't have the heat resistance properties that cast iron does and to make an aluminum block last as long as cast iron in an FI application, the addition of iron sleeve liners are sometimes recommended to resist the higher heat generated within the cylinder.
Note: This is NOT saying aluminum is unsuitable for FI applications at all. However, contemporary all-aluminum engines that are designed to be turbocharged are engineered from the design phase through production with higher grade aluminum, different sizing and densities, and in general, designed to withstand turbo/supercharged applications.
Saved the "best" for last.... THE biggest enemy of an FI engine (any engine actually but many fold worse in an FI engine) and perhaps the most highly overlooked when building a forced induction engine is DETONATION.
This can come from many things; but the two biggest culprits are:
- Insufficient fuel to properly match the incoming pressurized air charge ("lean out" or, slightly more scientifically, the stoichiometric A/F mix is askew... higher than 14.7:1) and...
- Insufficient or mistimed spark.
So you have this engine that is now receiving a super dense air entering the engine thanks to the air-charger(s). The resulting what-ifs that can lead to premature failure or outright destruction:
- What if the spark isn't hot enough to ignite it properly and fully?
- What if said spark occurs during the wrong portion of the combustion cycle, e.g., too early, too late?
- What if there's more air than fuel? (Meaning, the builder hasn't upsized the volume of fuel delivery or it's not functioning properly.... higher capacity pump, larger injectors.)
Disaster happens.
Any/all of these lead to detonation, which, I don't need to tell anyone who's taken Auto Shop 101, is deadly and will likely cause massive engine failure from these mini-hand-grenades going off in rapid sequence internally if left unchecked.
To properly prevent this, ALL of the mechanical ignition components (coilpacks, wiring, distributor/magneto (in such applications), plugs, etc.) ALL need to be upgraded to match the new parameters the engine is forced (no pun intended) to run under.
Generally speaking, when factories design their cars with factory turbo engines, you can bet these components are all upgraded (and often carried "down" to their normally aspirated brethren to cut overall costs by keeping the components consistent) before testing.
AND, more importantly, in addition to the hardware, the brain mapping (ECU parameters) - the software side - is all different. Timing curves (advance and retard points - and all facets of spark control) need to be mated to all of the engine's new different-from-stock operating conditions: boost pressure, engine speed, fuel pressure, MAF readings, knock sensor(s), O2 readings, all happening simultaneously to interpret and maintain what's going on inside the engine.
--------------------------------------
I could go on and on and on but this is a cursory look at why a turbo or supercharged engine - especially one done after the fact like any/all aftermarket systems - are more stressful to an engine.
Hope this helps to answer the question, T'bo (and any other interested parties).
06-15-2016, 08:29 PM
#55
350Z/370Z Tech Moderator
MY350Z.COM
MY350Z.COM
This is the kind of answer i was looking for. So basically if all things equal, the only extra stress would be the pressure from the force air. But since this is the real world and variable exists, FI stresses the engine due to other variables. And factory FO cars simply have these variable are mimized and there for have less stress, per say, than an aftermarket one.
There's other things I didn't mention like heat stress from one or two hot turbos mounted underhood, extra plumbing for oil and intercooling that introduce new potential points of failure. And I won't here.
The essence is what you distilled in your one paragraph.
06-16-2016, 04:37 AM
#56
General & DIY Moderator
MY350Z.COM
MY350Z.COM
iTrader: (64)
This is the kind of answer i was looking for. So basically if all things equal, the only extra stress would be the pressure from the force air. But since this is the real world and variable exists, FI stresses the engine due to other variables. And factory FO cars simply have these variable are mimized and there for have less stress, per say, than an aftermarket one.
06-16-2016, 05:03 AM
#57
Registered User
Thread Starter
If THIS is the type of answer you're looking for, all I can say is, you're lucky that Mic took a deep breathe and put together a comprehensive answer. For the purposes of this forum, the only thing to add is any variance from factory parameters (think 1000 hp R35s) will also stress the engine even though it was designed for FI. That REALLY applies to users of this forum, who might take a cursory look at this thread and think that FI for their VQ is not stressful. Plenty of early adopters just added FI and found there's a VERY limited shelf life to that plan.
I am lucky and glad not just for mic but for everyone who chimed in. Ive understood that other variables stresses the engine. My main question was about the air being forced in, if that itself stresses the engine. But i do thank everyone who tried to explained it. And especially mic for going wikia on us.
06-18-2016, 05:41 PM
#60
Take your theoretical stock non-FI engine, and run it theoretically at 39,000 feet BELOW sea level in air (not water), which would make the stock engine receive ~65.5 vs ~14.7 atmospheric pressure compared to sea level on stock DE rods. What do you think will happen? Why do you think it happened?
Submit this topic to Mythbusters to petition them to do new episodes, I'd love to see the look on Jaimie's face as he reads thru this thread's compelling arguments, or could be a plot to a prequel to Jim Carey and Jeff Daniel's movie.
Answer to feed the trolls more glorious crap: Oh cheese and crackers, a car engine is designed to meet certain requirements. N/A or FI. Said design is only certified and produced after determined to meet those requirements to a target that from a statistical reliability standpoint is acceptable to said manufacture. Going aftermarket FI on a N/A produced engine leads to a change in requirements, which very likely the original design was not created to meet, AKA can fail a lot quicker, immediately, or later in the future depending on the wider reaching capability of the original design whether intended or unexpectedly. FI engines from factory are typically beefier to handle the added stresses of the operational environment they are targeted for. N/A engines usually are not as beefy as the beefier engines require more/stronger/different materials/solutions which amounts to more cost. The car manufactures want to produce something to the consumer at the cheapest price to maximize profits while maintaining enough reliability to ensure the consumer is happy with their car for the life of the warranty or longer for likely brand purposes. So N/A cars are typically pretty 'weak' in terms of strength in what they can handle because a manufacture is not going to produce a car with an engine that is capable of handling FI and 2,000 WHP if all it needs is 200 BHP to stay competitive with their competition and within a price-point of say $15,000. A engine that can handle that kind of power will likely cost $30,000++++, so way over the cost of the entire car for just an engine as just an example. When you as a consumer go tacking on nitrous/blowers/turbo's on a stock N/A engine, you void the warranty because the manufacture knows the car was not designed for that, aka you are risking your own cars engine health and longevity, and they are not going to risk having to support you using their manufactured product outside of the requirements they original designed it for. What does this mean? Yes, FI is more stressful on a motor than N/A, adding on to that, you can say FI is more stressful for even an FI motor. Why? Because pushing a motor well past even FI engineered requirements still means you are bypassing the intended design, duh. Your trying to get all star trek technical on an otherwise simple concept - something is designed for X, if your trying to use it like Y, do not expect it to always be successful. Design and build for Y if that is your goal. On another note, water is wet.
Submit this topic to Mythbusters to petition them to do new episodes, I'd love to see the look on Jaimie's face as he reads thru this thread's compelling arguments, or could be a plot to a prequel to Jim Carey and Jeff Daniel's movie.
Answer to feed the trolls more glorious crap: Oh cheese and crackers, a car engine is designed to meet certain requirements. N/A or FI. Said design is only certified and produced after determined to meet those requirements to a target that from a statistical reliability standpoint is acceptable to said manufacture. Going aftermarket FI on a N/A produced engine leads to a change in requirements, which very likely the original design was not created to meet, AKA can fail a lot quicker, immediately, or later in the future depending on the wider reaching capability of the original design whether intended or unexpectedly. FI engines from factory are typically beefier to handle the added stresses of the operational environment they are targeted for. N/A engines usually are not as beefy as the beefier engines require more/stronger/different materials/solutions which amounts to more cost. The car manufactures want to produce something to the consumer at the cheapest price to maximize profits while maintaining enough reliability to ensure the consumer is happy with their car for the life of the warranty or longer for likely brand purposes. So N/A cars are typically pretty 'weak' in terms of strength in what they can handle because a manufacture is not going to produce a car with an engine that is capable of handling FI and 2,000 WHP if all it needs is 200 BHP to stay competitive with their competition and within a price-point of say $15,000. A engine that can handle that kind of power will likely cost $30,000++++, so way over the cost of the entire car for just an engine as just an example. When you as a consumer go tacking on nitrous/blowers/turbo's on a stock N/A engine, you void the warranty because the manufacture knows the car was not designed for that, aka you are risking your own cars engine health and longevity, and they are not going to risk having to support you using their manufactured product outside of the requirements they original designed it for. What does this mean? Yes, FI is more stressful on a motor than N/A, adding on to that, you can say FI is more stressful for even an FI motor. Why? Because pushing a motor well past even FI engineered requirements still means you are bypassing the intended design, duh. Your trying to get all star trek technical on an otherwise simple concept - something is designed for X, if your trying to use it like Y, do not expect it to always be successful. Design and build for Y if that is your goal. On another note, water is wet.
Last edited by Juztin; 06-18-2016 at 05:49 PM.