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Why DIrect Injection is really bad!
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Originally Posted By: UncleDave
Intake track and valve deposits are one of the reasons Ford designed the 2017 Ecoboost with a dual fuel system DI, and port injection.
You know this how? It most likely was a combination of many factors with intake deposits being low on the list as in the past 8 years of the EB 3.5 it doesn't really have issues with the deposits that affect performance. It could very well be fuel economy, performance, emissions, or a bunch of other reasons. Doubtful anyone will find the real reason though.
Intake track and valve deposits are one of the reasons Ford designed the 2017 Ecoboost with a dual fuel system DI, and port injection.
You know this how? It most likely was a combination of many factors with intake deposits being low on the list as in the past 8 years of the EB 3.5 it doesn't really have issues with the deposits that affect performance. It could very well be fuel economy, performance, emissions, or a bunch of other reasons. Doubtful anyone will find the real reason though.
Major Engineering decisions are rarely made due to any one factor these days. There is always the aim for more... power, efficiency, cleanliness, happiness, smoothness...
I just thought I would add one more thing before this becomes a dead thread...
In my first post, I said that whilst oily intake deposits don't particularly look good, they aren't anything like as harmful as the oil that makes it through the intake and into the cylinders to be burnt. Burnt oil makes for dirty pistons, stuck rings and all sorts of bad stuff you don't want to experience in real life.
Well I stumbled upon some nice, illustrative piston photographs in the blurb for Eneos's Sustina engine oils. Please have a look at these by clicking on the link below...
http://www.eneos.us/products/sustina-enhanced-performance-motor-oil/
These pictures are of pistons taken from the industry standard Sequence IIIG test. The test uses a 1996 GM V6 engine which runs for 100 hours continuous at 3600 rpm and with the engine bulk oil temperature kept at the relatively high temperature of 150°C.
Three pistons are shown. The bottom one is very dirty representing GF-4 quality. The middle one is still dirty but marginally better and supposedly represents GF-5 oil quality. The top piston is very clean and represents what you purportedly see with Eneos's synthetic oil. In terms of Weighted Piston Deposits (where 0 is God awful and 10 is pristine), I'd guess you are looking at ratings of 3.5, 4.0 and about 7.5.
Now you're going to have to trust me on this but what I would say you're actually looking at is...
a) a Group II oil with a Noack of 14 - 15%
b) a Group II/II+ oil with a Noack of 12 - 14%
c) a Group III/IV oil with a Noack of below 10%
This should give you some idea of how Noack potentially impacts on piston cleanliness and why it's a good idea to go with a low Noack oil.
As an aside, you might ask yourself the question why the API & ILSAC ever got it into their stupid heads that the bottom & middle pistons represented an 'acceptable' level of oil performance for GF-4 & GF-5? (especially when you realise that this extreme level of deposit was laid down over just one OCI!) You might also ask, if this is what high Noack oil does to pistons, why the API & ILSAC haven't taken steps to further reduce the Noack spec from 15%? After all, European PCMOs have limited Noack to 13% max for years and dexos oils have also moved to this limit. From what I've read, the 15% Noack max limit will carry over into GF-6. It's insane!
In my first post, I said that whilst oily intake deposits don't particularly look good, they aren't anything like as harmful as the oil that makes it through the intake and into the cylinders to be burnt. Burnt oil makes for dirty pistons, stuck rings and all sorts of bad stuff you don't want to experience in real life.
Well I stumbled upon some nice, illustrative piston photographs in the blurb for Eneos's Sustina engine oils. Please have a look at these by clicking on the link below...
http://www.eneos.us/products/sustina-enhanced-performance-motor-oil/
These pictures are of pistons taken from the industry standard Sequence IIIG test. The test uses a 1996 GM V6 engine which runs for 100 hours continuous at 3600 rpm and with the engine bulk oil temperature kept at the relatively high temperature of 150°C.
Three pistons are shown. The bottom one is very dirty representing GF-4 quality. The middle one is still dirty but marginally better and supposedly represents GF-5 oil quality. The top piston is very clean and represents what you purportedly see with Eneos's synthetic oil. In terms of Weighted Piston Deposits (where 0 is God awful and 10 is pristine), I'd guess you are looking at ratings of 3.5, 4.0 and about 7.5.
Now you're going to have to trust me on this but what I would say you're actually looking at is...
a) a Group II oil with a Noack of 14 - 15%
b) a Group II/II+ oil with a Noack of 12 - 14%
c) a Group III/IV oil with a Noack of below 10%
This should give you some idea of how Noack potentially impacts on piston cleanliness and why it's a good idea to go with a low Noack oil.
As an aside, you might ask yourself the question why the API & ILSAC ever got it into their stupid heads that the bottom & middle pistons represented an 'acceptable' level of oil performance for GF-4 & GF-5? (especially when you realise that this extreme level of deposit was laid down over just one OCI!) You might also ask, if this is what high Noack oil does to pistons, why the API & ILSAC haven't taken steps to further reduce the Noack spec from 15%? After all, European PCMOs have limited Noack to 13% max for years and dexos oils have also moved to this limit. From what I've read, the 15% Noack max limit will carry over into GF-6. It's insane!
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Toyota stated way back when they built the intake system for the BRZ that an extra injector or two in the intake for a DI engine was for part throttle cylinder filling issues. Porsche has also acknowledged part throttle issues with DI. There is obviously a learning curve here.
And that engine looks fine other than the cracked ports!
And that engine looks fine other than the cracked ports!
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Originally Posted By: SteveSRT8
And that engine looks fine other than the cracked ports!
They are not cracked, it is a casting mark. They all look like that.
And that engine looks fine other than the cracked ports!
They are not cracked, it is a casting mark. They all look like that.
Originally Posted By: mightymousetech
Originally Posted By: SteveSRT8
And that engine looks fine other than the cracked ports!
They are not cracked, it is a casting mark. They all look like that.
Judging from the pictures, I don't think these are casting marks. For one they all look a bit different and second, a structural area like that would not have two die halves meet in that spot.
Originally Posted By: SteveSRT8
And that engine looks fine other than the cracked ports!
They are not cracked, it is a casting mark. They all look like that.
Judging from the pictures, I don't think these are casting marks. For one they all look a bit different and second, a structural area like that would not have two die halves meet in that spot.
Those cast marks are definitely 100% normal and NOT a reason for concern.
It's a J35A4, yes it has 202k miles, no this has nothing to do with DI.
My main point was that the new J35's just slapped in DI injectors in place of Port injectors. None of the PCV system was changed much at all, so while I love Honda - I am rather unhappy that the cars have no foreseeable future after the warranty period expires.
These pics look great for 202k miles; but even with 25% the amount of [censored] in there - the new engines will start to get ignition failures from caked over intake valves. Intake valves need to be completely clean to seal the cylinder completely.
I'm not moaning and complaining - this post was just to show people who are contemplating a DI engine what kind of buildup exists on the intake side of the motor, and that they shouldn't listen to the whole "technology is advancing, you'll have no problems!" hullabaloo that salesmen use to lie to you and get you to buy the garbage they have on the lots. This sentiment does not apply to DI engines with port injectors though. Toyota, you are the industrys' hero!
My main point was that the new J35's just slapped in DI injectors in place of Port injectors. None of the PCV system was changed much at all, so while I love Honda - I am rather unhappy that the cars have no foreseeable future after the warranty period expires.
These pics look great for 202k miles; but even with 25% the amount of [censored] in there - the new engines will start to get ignition failures from caked over intake valves. Intake valves need to be completely clean to seal the cylinder completely.
I'm not moaning and complaining - this post was just to show people who are contemplating a DI engine what kind of buildup exists on the intake side of the motor, and that they shouldn't listen to the whole "technology is advancing, you'll have no problems!" hullabaloo that salesmen use to lie to you and get you to buy the garbage they have on the lots. This sentiment does not apply to DI engines with port injectors though. Toyota, you are the industrys' hero!
Originally Posted By: JDMHero47
It's a J35A4, yes it has 202k miles, no this has nothing to do with DI.
My main point was that the new J35's just slapped in DI injectors in place of Port injectors. None of the PCV system was changed much at all, so while I love Honda - I am rather unhappy that the cars have no foreseeable future after the warranty period expires.
These pics look great for 202k miles; but even with 25% the amount of [censored] in there - the new engines will start to get ignition failures from caked over intake valves. Intake valves need to be completely clean to seal the cylinder completely.
I'm not moaning and complaining - this post was just to show people who are contemplating a DI engine what kind of buildup exists on the intake side of the motor, and that they shouldn't listen to the whole "technology is advancing, you'll have no problems!" hullabaloo that salesmen use to lie to you and get you to buy the garbage they have on the lots. This sentiment does not apply to DI engines with port injectors though. Toyota, you are the industrys' hero!
Just one last thing to say...
If you have an intake system where there are a lot of visible oily deposits, you should in one respect be glad that this crud didn't make it to the cylinders to get burnt. One of the lesser known features of MPI gasoline detergents is whilst they reduce Inlet Valve Deposits (IVDs), they INCREASE Combustion Chamber Deposits (CCDs). What gets washed off must go somewhere!
In a normal MPI engine, this increase in CCDs isn't such a big deal. However, for TGDI engines, CCDs aren't going to good for LSPI. Also, although the official line is Noack doesn't impact on LSPI, I'm not convinced. If you don't want CCDs, run a low Noack oil.
It's a J35A4, yes it has 202k miles, no this has nothing to do with DI.
My main point was that the new J35's just slapped in DI injectors in place of Port injectors. None of the PCV system was changed much at all, so while I love Honda - I am rather unhappy that the cars have no foreseeable future after the warranty period expires.
These pics look great for 202k miles; but even with 25% the amount of [censored] in there - the new engines will start to get ignition failures from caked over intake valves. Intake valves need to be completely clean to seal the cylinder completely.
I'm not moaning and complaining - this post was just to show people who are contemplating a DI engine what kind of buildup exists on the intake side of the motor, and that they shouldn't listen to the whole "technology is advancing, you'll have no problems!" hullabaloo that salesmen use to lie to you and get you to buy the garbage they have on the lots. This sentiment does not apply to DI engines with port injectors though. Toyota, you are the industrys' hero!
Just one last thing to say...
If you have an intake system where there are a lot of visible oily deposits, you should in one respect be glad that this crud didn't make it to the cylinders to get burnt. One of the lesser known features of MPI gasoline detergents is whilst they reduce Inlet Valve Deposits (IVDs), they INCREASE Combustion Chamber Deposits (CCDs). What gets washed off must go somewhere!
In a normal MPI engine, this increase in CCDs isn't such a big deal. However, for TGDI engines, CCDs aren't going to good for LSPI. Also, although the official line is Noack doesn't impact on LSPI, I'm not convinced. If you don't want CCDs, run a low Noack oil.
Originally Posted By: zzyzzx
3 pages an no suggestions to use Seafoam?
Made for Mitsubishi GDI engines.
3 pages an no suggestions to use Seafoam?
Made for Mitsubishi GDI engines.
Originally Posted By: KrisZ
Originally Posted By: mightymousetech
Originally Posted By: SteveSRT8
And that engine looks fine other than the cracked ports!
They are not cracked, it is a casting mark. They all look like that.
Judging from the pictures, I don't think these are casting marks. For one they all look a bit different and second, a structural area like that would not have two die halves meet in that spot.
I have had hundreds of these engines apart, they all look exactly like that.
Originally Posted By: mightymousetech
Originally Posted By: SteveSRT8
And that engine looks fine other than the cracked ports!
They are not cracked, it is a casting mark. They all look like that.
Judging from the pictures, I don't think these are casting marks. For one they all look a bit different and second, a structural area like that would not have two die halves meet in that spot.
I have had hundreds of these engines apart, they all look exactly like that.
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