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What's the ideal injector trajectory angle?

General engine tech -- Drag Racing to Circle Track

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MadBill
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Re: What's the ideal injector trajectory angle?

Post by MadBill » Sun Sep 01, 2019 8:48 pm

gmrocket wrote:
Sun Sep 01, 2019 12:37 am
...Doesn't our gas have to meet pretty high minimum standard?
Per: https://en.wikipedia.org/wiki/Top_Tier_ ... t_Gasoline , the EPA sets the bar pretty low. In addition many suppliers are non-conforming and illegal disposal of waste chemicals in '"gasoline" is a significant issue.
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.

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Re: What's the ideal injector trajectory angle?

Post by peejay » Mon Sep 02, 2019 11:04 am

gmrocket wrote:
Fri Aug 30, 2019 7:05 am
This is the reason I'm asking ...this is a head I done recently which was one of the worst for carbon build up in the intake port...1/4" thick which had to be chiseled out .

It was a low mile clean well cared for engine, ran great. 2002 6ltr LQ9 #317 heads. The backside of the intakes also had really thick buildup.

The chamber burn looks clean and good top of piston was a nice tan color with no hard deposits

So why did this thing have such a buildup..one of the worst I've seen
It wasn''t well cared for.

Cheap oil, cheap fuel, lots of idle time instead of WOT.

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Re: What's the ideal injector trajectory angle?

Post by j-c-c » Tue Sep 03, 2019 5:28 pm

mk e wrote:
Sun Sep 01, 2019 7:37 am
I just read Dollar Tree (iirc) has to pay $1.2M in restitution in new york state for selling motor oil that "isn't appropriate of any engine manufactured after 1930" I think is what it said. When money is involve people will cheat and lie about anything.
But in all fairness, since that is likely legal munbo jumbo to exact maximum penalty from the defendant, that could only mean they for example they had an incorrect label on the container, rather then the oil itself was inferior. For example, I believe the public is in sheep mode with the thinking a higher rated oil "SN" vs say "SL" is automatically "better". Newer, more extensively tested, etc, but "better" might just be rather subjective to the application. Same applies to public understanding of "regular" fuel vs "Premium" Your last comment however is spot on. =D>

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Re: What's the ideal injector trajectory angle?

Post by midnightbluS10 » Wed Sep 04, 2019 7:08 am

j-c-c wrote:
Tue Sep 03, 2019 5:28 pm
mk e wrote:
Sun Sep 01, 2019 7:37 am
I just read Dollar Tree (iirc) has to pay $1.2M in restitution in new york state for selling motor oil that "isn't appropriate of any engine manufactured after 1930" I think is what it said. When money is involve people will cheat and lie about anything.
But in all fairness, since that is likely legal munbo jumbo to exact maximum penalty from the defendant, that could only mean they for example they had an incorrect label on the container, rather then the oil itself was inferior. For example, I believe the public is in sheep mode with the thinking a higher rated oil "SN" vs say "SL" is automatically "better". Newer, more extensively tested, etc, but "better" might just be rather subjective to the application. Same applies to public understanding of "regular" fuel vs "Premium" Your last comment however is spot on. =D>
How do you conclude from "isn't appropriate in any engine after 1930" that they didn't have inferior oil but wrong labels?

Are we reading the same thing? I'd suspect both, if anything. Shitty oil labeled as something better. Or knowing them, it likely wasn't even API approved oil. I've seen that in plenty of convenience stores, etc... No API Starburst anywhere on the label with something like an SA rating.
JC -

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Re: What's the ideal injector trajectory angle?

Post by adam728 » Wed Sep 04, 2019 12:48 pm

According to what I found, the oil is labeled as API-SA (30W) and API-SF (10W-30), and contains a warning against using in newer vehicles. The reason they got sued was for putting the oil next to other name brand, modern oils, which is claimed to be a misrepresentation.

https://clark.com/story/dollar-general- ... motor-oil/
Dollar General was sued June 5 by the Attorney General of the state of New Mexico for “wrongfully representing” that its store brand of oils are comparable to brand-name products. At issue is the rating of the oils (aka service classification), which is determined by the American Petroleum Institute (API). There are three groupings of service classifications: Current, obsolete or obsolete/can cause equipment harm.

Dollar General also sells SAE 30 oil with the following disclaimer: “Caution – This oil is rated API SA. It contains no additives. It is not suitable for use in most gasoline powered automotive engines built after 1930. Use in modern engines may cause unsatisfactory engine performance or equipment harm.” Using that stuff in a modern engine would likely cause equipment harm, according to the API’s service classification.

Here’s what is at issue:
Clearly, it’s an indisputable fact that Dollar General sells some outdated oil that won’t work in many cars on the road today.What is up for dispute is whether or not the company is guilty of “wrongfully representing” that its store brand of oils are comparable to brand-name products because of their placement in stores.
“Positioning its DG Auto obsolete motor oil immediately adjacent to the more expensive brand-name motor oil, wrongfully [represents] that its obsolete motor oil is lower-priced but comparable to the brand-name products,” the Attorney General’s complaint alleges.

The Attorney General also alleges that the dollar store has “done significant harm to New Mexico’s pristine air quality by selling obsolete motor oil that was unknowingly used by its customers in modern vehicles, damaging engines and deactivating emission control equipment that is required to reduce and control the emission of harmful pollutants.”

New Mexico joins 14 other states in suing the retailer over its motor oil, according to MousePrint.org.
oil2.png
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gmrocket
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Re: What's the ideal injector trajectory angle?

Post by gmrocket » Thu Sep 05, 2019 5:08 am

Internally the engine was really clean, no goop in the oil pan or valley area. The block and heads internally was not dark or discolored. Bearings all looked like new.

Just the intake ports has a heavy build up.

Is there an ideal or best spray pattern?

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Re: What's the ideal injector trajectory angle?

Post by Belgian1979 » Thu Sep 05, 2019 6:23 am

gmrocket wrote:
Fri Aug 30, 2019 7:05 am
This is the reason I'm asking ...this is a head I done recently which was one of the worst for carbon build up in the intake port...1/4" thick which had to be chiseled out .

It was a low mile clean well cared for engine, ran great. 2002 6ltr LQ9 #317 heads. The backside of the intakes also had really thick buildup.

The chamber burn looks clean and good top of piston was a nice tan color with no hard deposits

So why did this thing have such a buildup..one of the worst I've seen
Doesn't look like fuel to me. I have a far from optimal injector angle and the only thing it does is wet the walls. It shows a a yellowish type color on the walls of the runner. Maybe oil is seeping in that then gets baked onto the walls ?

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Re: What's the ideal injector trajectory angle?

Post by gmrocket » Thu Sep 05, 2019 11:53 am

Belgian1979 wrote:
Thu Sep 05, 2019 6:23 am
gmrocket wrote:
Fri Aug 30, 2019 7:05 am
This is the reason I'm asking ...this is a head I done recently which was one of the worst for carbon build up in the intake port...1/4" thick which had to be chiseled out .

It was a low mile clean well cared for engine, ran great. 2002 6ltr LQ9 #317 heads. The backside of the intakes also had really thick buildup.

The chamber burn looks clean and good top of piston was a nice tan color with no hard deposits

So why did this thing have such a buildup..one of the worst I've seen
Doesn't look like fuel to me. I have a far from optimal injector angle and the only thing it does is wet the walls. It shows a a yellowish type color on the walls of the runner. Maybe oil is seeping in that then gets baked onto the walls ?
Oil seeping into all 8 intake ports?

We have tail pipe emissions testing here so I don't know how it could have passed with that big of a problem.

It wasn't oil build up, it looks black in the picture but it was tan under the surface, just like buildup in a combustion chamber.

The thickest buildup was on the deflection wing beside the valve guide.

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Re: What's the ideal injector trajectory angle?

Post by magwillfl » Thu Sep 05, 2019 12:33 pm

gmrocket wrote:
Thu Sep 05, 2019 11:53 am
Belgian1979 wrote:
Thu Sep 05, 2019 6:23 am
gmrocket wrote:
Fri Aug 30, 2019 7:05 am
This is the reason I'm asking ...this is a head I done recently which was one of the worst for carbon build up in the intake port...1/4" thick which had to be chiseled out .

It was a low mile clean well cared for engine, ran great. 2002 6ltr LQ9 #317 heads. The backside of the intakes also had really thick buildup.

The chamber burn looks clean and good top of piston was a nice tan color with no hard deposits

So why did this thing have such a buildup..one of the worst I've seen
Doesn't look like fuel to me. I have a far from optimal injector angle and the only thing it does is wet the walls. It shows a a yellowish type color on the walls of the runner. Maybe oil is seeping in that then gets baked onto the walls ?
Oil seeping into all 8 intake ports?

We have tail pipe emissions testing here so I don't know how it could have passed with that big of a problem.

It wasn't oil build up, it looks black in the picture but it was tan under the surface, just like buildup in a combustion chamber.

The thickest buildup was on the deflection wing beside the valve guide.
The early LS engines had a terrible PCV system that sucked a lot of oil into the intake manifold, which tended to create the build up due to heat. Around 2003 a PCV valve with a smaller opening was used, and in subsequent years the PCV system was revised even more.

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Re: What's the ideal injector trajectory angle?

Post by gmrocket » Thu Sep 05, 2019 2:40 pm

Ok, what does hardened oil deposits look like if you break them up? All black and like a soft charcoal, or light tan color and very hard?

Hard to believe it's oil since the combustion chamber and piston crown look good...clean and nice tan color.

It looks black and wet, yet just under that surface is very hard , like a rock ,tan colored

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