highfigh

highfigh

Audioholic Overlord
"The big disadvantage of direct injection is carbon buildup on the backside of the intake valves. This can throw a computer code, and could result with an engine miss or a ignition failure. The other disadvantage of direct injection is cost. The injector tips are mounted right into the combustion chamber, so the materials of the injector have to be very good quality."
What was the source for this quote?
 
Irvrobinson

Irvrobinson

Audioholic Spartan
While I recognize the benefits of direct injection, I'm still a bit leery. These systems a far more complex than port injection systems and it isn't a free lunch, by any means. The added complexity adds up-front costs as well as more expensive repairs down the road. I just came across this article, which was quite educational:
https://stillrunningstrong.com/car-technology/gasoline-direct-injection/
I had no idea that, while reducing CO2 emissions, GDI actually increases particulate emissions to diesel-like numbers. If I ever end up buying a vehicle with GDI (both of our current vehicles have PFI),I'll install an oil separator. My hope is that by the time we need a new vehicle, going electric will be a practical option.
In the US the supposed dire consequences quoted in these articles, like misfires as early as 20,000 miles, would result in an emissions control recall. I'm not familiar with laws in other countries. So I doubt this is much more than click bait. Also, the article talks about the intake valve coking problem without discussing that this is caused by poor design in some implementations, which I suspect also increases particulates emissions. Retrofitting a maintenance-free air oil separator is probably costly, which is why we''re seeing port/direct combo work-arounds, not to mention cheap high pressure fuel pumps that are very noisy, so when the port injectors are working you can run the lower pressure pump. The combo systems look like a future repair complexity problem.

We are in complete agreement about electric. A superior technology in every way, except recharge times, range, and battery cost.
 
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O

Out-Of-Phase

Audioholic Chief
As a strategy for getting around the limitations of cheap direct-injection designs.
Can you show some examples of your fuel-injection designs and how they were implemented? Are you a mechanical engineer employed by a major automobile manufacturer?
 
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Irvrobinson

Irvrobinson

Audioholic Spartan
Can you show some examples of your fuel-injection designs and how they were implemented? Are you a mechanical engineer employed by a major automobile manufacturer?
You're very funny. It does not take much of an expert to know that leaving off an air oil separator is a really stupid cost savings. Have you ever removed the intake manifold from a vehicle with a PCV system and no separator and seen what the inside of the manifold looks like? In fact, it makes such a mess that what a lot of dummies do when they see the oil on older domestic V8s they replace the PCV system with a vent to the atmosphere, which looks like this:

https://www.amazon.com/Moroso-68811-Valve-Filtered-Breather/dp/B000CON36M/ref=asc_df_B000CON36M/?tag=hyprod-20&linkCode=df0&hvadid=265897533585&hvpos=1o1&hvnetw=g&hvrand=4710752752510687676&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030455&hvtargid=pla-680376865608&psc=1
 
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O

Out-Of-Phase

Audioholic Chief
You're very funny. It does not take much of an expert to know that leaving off an air oil separator is a really stupid cost savings. Have you ever removed the intake manifold from a vehicle with a PCV system and no separator and seen what the inside of the manifold looks like? In fact, it makes such a mess that what a lot of dummies do when they see the oil on older domestic V8s they replace the PCV system with a vent to the atmosphere, which looks like this:

https://www.amazon.com/Moroso-68811-Valve-Filtered-Breather/dp/B000CON36M/ref=asc_df_B000CON36M/?tag=hyprod-20&linkCode=df0&hvadid=265897533585&hvpos=1o1&hvnetw=g&hvrand=4710752752510687676&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030455&hvtargid=pla-680376865608&psc=1
Why am I funny? I'll ask again, are you a mechanical engineer? Or even an ASE certified auto mechanic? Can you share your knowledge and experience with the major auto makers and even local auto mechanics in your area? Have you contacted any auto manufacturers with your research and ideas? The amazon link you provided, did you design that device? The auto industry could use you.

Share your ideas:
https://corporate.ford.com/innovation/innovation-ideas-submission.html
https://www.gmideas.com/gmideas/ideas?action=NewIdea
http://www.ideaincite.com/Chrysler/Ideas
 
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Irvrobinson

Irvrobinson

Audioholic Spartan
Why am I funny?
Because you appear to be trying to make a formal background in a subject a prerequisite for participating in a discussion on this forum. If that happened, this would be a very quiet forum indeed!

I'll ask again, are you a mechanical engineer?
No.

Or even an ASE certified auto mechanic?
No, although by many people's measures I am a pretty decent mechanic. The difference between me and professional mechanics is that by experience they learn efficient methods for certain procedures, whereas I often take several times longer because I'm discovering the efficient ways to do things as I go, and I may not repeat the procedure for years. On the other hand, I seem to have a better grasp of the theory behind how certain subsystems work and why they work like that than most professional mechanics I run into.

Can you share your knowledge and experience with the major auto makers and even local auto mechanics in your area?
I have never discussed anything with an auto manufacturer, and I suspect all of their engineers are more knowledgeable than I am. As for local mechanics, I once made a big bet with a Chevy dealer's service department. We had a 2003 Z06 that was in a head-on collision (with me in it). The insurance company decided not to total it, so it was repaired. The car came back from the dealer's shop making a funny noise emanating from the driver-side front wheel. I took the car back to the dealer and told them the wheel bearing was damaged and needed to be replaced as a safety issue. The mechanic and the service department GM test drove the car and said "no way". I told them to replace it, and if the bearing was damaged the repair was on them, and if I was wrong I'd pay full retail price for it. A job like that usually costs over a thousand dollars on a C5 Corvette at a dealer, even back then. Later that day I got a phone call that the wheel bearing was replaced for no charge. That made me smile.

Have you contacted any auto manufacturers with your research and ideas?
No. They don't need me.

The amazon link you provided, did you design that device? The auto industry could use you.
No, I didn't, and I wouldn't. The part I referenced is an ecological disaster, and causes a car it's installed on to emit more hydrocarbons into the atmosphere than, I would estimate, over one hundred cars with properly functioning PCV systems.
 
O

Out-Of-Phase

Audioholic Chief
No. They don't need me.
Oh come now Irv, you're just being modest. Just think, the next vehicle I buy could have engineering designs and ideas that came from directly from you. That's why I provided those idea links. The big (3) US auto manufacturers don't know how lucky they are to have you.
 
Irvrobinson

Irvrobinson

Audioholic Spartan
Oh come now Irv, you're just being modest. Just think, the next vehicle I buy could have engineering designs and ideas that came from directly from you. That's why I provided those idea links. The big (3) US auto manufacturers don't know how lucky they are to have you.
Thanks, but I know the difference between hobbyist knowledge and real in-depth professional knowledge in a field, and I know that for automotive engineering I'm a poetry reader, not a poet.
 
GO-NAD!

GO-NAD!

Audioholic Ninja
In the US the supposed dire consequences quoted in these articles, like misfires as early as 20,000 miles, would result in an emissions control recall. I'm not familiar with laws in other countries. So I doubt this is much more than click bait. Also, the article talks about the intake valve coking problem without discussing that this is caused by poor design in some implementations, which I suspect also increases particulates emissions. Retrofitting a maintenance-free air oil separator is probably costly, which is why we''re seeing port/direct combo work-arounds, not to mention cheap high pressure fuel pumps that are very noisy, so when the port injectors are working you can run the lower pressure pump. The combo systems look like a future repair complexity problem.

We are in complete agreement about electric. A superior technology in every way, except recharge times, range, and battery cost.
Clickbait? LOL, I don't think so. As a marine engineering technologist, I have a pretty good grasp of ICE operating principles. Although my knowledge of emissions control systems is pretty cursory - the marine diesels I operated and maintained had none, essentially - what the author says makes sense to me.

Maybe I'm going blind, but I read through the article a couple more times and couldn't find any mention of misfires at 20,000 miles. And, although he didn't explicitly state that carbon buildup on intake valves in GDI engines was caused by poor design, he did mention that the problem has been ameliorated in later designs - so he implied it, at least.
 
highfigh

highfigh

Audioholic Overlord
In the US the supposed dire consequences quoted in these articles, like misfires as early as 20,000 miles, would result in an emissions control recall. I'm not familiar with laws in other countries. So I doubt this is much more than click bait. Also, the article talks about the intake valve coking problem without discussing that this is caused by poor design in some implementations, which I suspect also increases particulates emissions. Retrofitting a maintenance-free air oil separator is probably costly, which is why we''re seeing port/direct combo work-arounds, not to mention cheap high pressure fuel pumps that are very noisy, so when the port injectors are working you can run the lower pressure pump. The combo systems look like a future repair complexity problem.

We are in complete agreement about electric. A superior technology in every way, except recharge times, range, and battery cost.
Why do you say the cost for direct injection is high? I find it hard to believe that the cost to use port and direct injection would be cheaper. They're using fuel injection in lawnmowers and small outboard motors.

WRT electric cars- what about the issue of how the charging power is generated?
 
highfigh

highfigh

Audioholic Overlord
I have never discussed anything with an auto manufacturer, and I suspect all of their engineers are more knowledgeable than I am. As for local mechanics, I once made a big bet with a Chevy dealer's service department. We had a 2003 Z06 that was in a head-on collision (with me in it). The insurance company decided not to total it, so it was repaired. The car came back from the dealer's shop making a funny noise emanating from the driver-side front wheel. I took the car back to the dealer and told them the wheel bearing was damaged and needed to be replaced as a safety issue. The mechanic and the service department GM test drove the car and said "no way". I told them to replace it, and if the bearing was damaged the repair was on them, and if I was wrong I'd pay full retail price for it. A job like that usually costs over a thousand dollars on a C5 Corvette at a dealer, even back then. Later that day I got a phone call that the wheel bearing was replaced for no charge. That made me smile.
Why would a wheel bearing replacement cost $1000?
 
Irvrobinson

Irvrobinson

Audioholic Spartan
Why would a wheel bearing replacement cost $1000?
This incident was in 2005, so my memory is being stretched, but the part alone was over $400. Even now if you do a search for a Corvette C5 front wheel bearing from AC Delco (only OEM parts, this was a dealer) you'll see that they go for $185 each from Advance Auto Parts, and dealers don't charge internet prices. Prices have also dropped on these parts since then, since they're not the latest thing and there's aftermarket competition. Then there's dealer labor rates, which were something like $100/hour, and (just guessing) about 3-4 hours of labor. Add in all of the disposal fees and shop fees and I don't think my guess was that far off, if it was at all.
 
Irvrobinson

Irvrobinson

Audioholic Spartan
Why do you say the cost for direct injection is high? I find it hard to believe that the cost to use port and direct injection would be cheaper. They're using fuel injection in lawnmowers and small outboard motors.

WRT electric cars- what about the issue of how the charging power is generated?
The injectors themselves are more expensive than port injectors, because they have to survive inside of a combustion chamber. The real cost difference, however, is in the much higher pressure fuel pump direct injection uses. Cheap high pressure fuel pumps, which are often derivatives of diesel pumps, make a lot of noise, one of the reasons I understand for the hybrid approaches.

Coal power generation in the US is on a fast decline. Even natural gas generation, along with power transmission losses on the grid (about 10%?) are better than the power consumed by oil refineries, pipelines, and last leg truck transport. Gasoline production is a really dirty business.
 
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Irvrobinson

Irvrobinson

Audioholic Spartan
Clickbait? LOL, I don't think so. As a marine engineering technologist, I have a pretty good grasp of ICE operating principles. Although my knowledge of emissions control systems is pretty cursory - the marine diesels I operated and maintained had none, essentially - what the author says makes sense to me.

Maybe I'm going blind, but I read through the article a couple more times and couldn't find any mention of misfires at 20,000 miles. And, although he didn't explicitly state that carbon buildup on intake valves in GDI engines was caused by poor design, he did mention that the problem has been ameliorated in later designs - so he implied it, at least.
The 20,000 mile quote was not from your linked article, it was one of the others. I said "articles", meaning not just yours.
 
GO-NAD!

GO-NAD!

Audioholic Ninja
The 20,000 mile quote was not from your linked article, it was one of the others. I said "articles", meaning not just yours.
OK, thanks for clarifying. I was thinking that I was going blind...
 
NINaudio

NINaudio

Senior Audioholic
Gasoline production is a really dirty business.
The mining of all the precious metals for the batteries is also a really dirty business. That being said, I've yet to see a study that includes the environmental impact of that mining. Are you aware of any?
 

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