Spark Plugs, difference between the Bosch and NGK pre/post facelift?

[infinkc]

Well the time has come for me to finally get new plugs.

According to audi the spark plug for the pre facelift is a Bosch 101905631G
the plug for the post facelift is a NGK 101905611G

My question, is there any reason that the post facelift plug wont work in the pre? there is a $30 difference between the 2 sets.

[PitchS4]

I replaced my OEM Bosch plugs (from the factory) with OEM NGK plugs from the dealer parts department. Same heat range. Go with whatever is cheaper.

[mr shickadance]

if you are tuned, you should consider going one step colder for whatever plug you plan on running.

also, keep to the manufacturer guidelines, slightly off topic, but in the subie world, (and I am sure I will get my companies mixed up but) if OEM called for NGK, and you ran bosch, you would see issues with the install of the bosch due to the washers they used....you had to be oddly specific with plugs and oil filters for subies, but I don't think audi has that issue.

[IanCH]

if you are tuned, you should consider going one step colder for whatever plug you plan on running.

There are no tuners that recommend this.

[mr shickadance]

it would not hurt, running increase boost and leaner conditions a step colder would help ignition.

[integroid]

also, keep to the manufacturer guidelines, slightly off topic, but in the subie world, (and I am sure I will get my companies mixed up but) if OEM called for NGK, and you ran bosch, you would see issues with the install of the bosch due to the washers they used....you had to be oddly specific with plugs and oil filters for subies, but I don't think audi has that issue.

I had a 600whp Subie before my S4 and never heard of this. I used NGK and Nippon without any issues at all. I was pretty deep in the Subaru world and never once heard of an issue with washers on a spark plug causing install problems? Granted most people stuck with NGK or Nippon since they are both OEM to Subaru.

[kielp]

I've been using the NGK 101905611G (PFR8S8EG) for about 10k miles on Stage II. I noticed no difference in performance. They're the same heat range (8) as stock and only about $12/each.

[Vogz]

it would not hurt, running increase boost and leaner conditions a step colder would help ignition.

It actually can hurt fuel mileage and part throttle response. Absolutely zero reason to run 1 step colder plugs in an S4 with just a little more boost.

[mr shickadance]

I had a 600whp Subie before my S4 and never heard of this. I used NGK and Nippon without any issues at all. I was pretty deep in the Subaru world and never once heard of an issue with washers on a spark plug causing install problems? Granted most people stuck with NGK or Nippon since they are both OEM to Subaru.

folks at EFI told me that the Bosch plugs did not seat right, I took them at their word given their high reputation.

[PitchS4]

if you are tuned, you should consider going one step colder for whatever plug you plan on running.

Please back this up with some actual data......

[mr shickadance]

increased boost + leaner conditions + high compression engine = potential pre-ignition problems

solution for this problem colder spark plug.

NGK's website

It depends on the modifications. The term "modified" refers to those engines that have received bolt-on improvements that may or may not raise the engine's total compression ratio. These can include turbocharging, supercharging, nitrous oxide injection, the use of smaller-chambered cylinder heads, modified piston configurations, free-flowing cylinder heads, change of induction components and/or the use of different fuel types and octane. These kinds of modifications generally require a change from stock spark plugs.

Modifications that will typically not require specialized plugs (in most cases the factory installed plug will be more than adequate) include adding a free-flowing air filter, headers, mufflers and rear-end gears. Basically, any modification that does not alter the overall compression ratio will not usually necessitate changing plug types or heat ranges. Such minor modifications will not significantly increase the amount of heat in the combustion chamber, hence, a plug change is probably not warranted.

However, when compression is raised, along with the added power comes added heat. Since spark plugs must remove heat and a modified engine makes more heat, the spark plug must remove more heat. A colder heat range spark plug must be selected and plug gaps should be adjusted smaller to ensure proper ignitability in this denser air/fuel mixture.

Typically, for every 75-100 hp you add, you should go one step colder on the spark plug's heat range. A hotter heat range is not usually recommended except when severe oil or fuel fouling is occurring.


http://www.ngksparkplugs.com/tech_su...d.asp?mode=nml


I know the first part of the FAQ is a bit misleading, but we are with our tunes adding a serious amount of HP, at stage 2, I would figure it's common sense to run a step colder but apparently not on this platform.

[mr shickadance]

another article calling for spark plug tuning, albeit lengthy, a good read.

if you are lazy, read from the bolded "heat range"

http://www.carcraft.com/techarticles/spark_plugs_tips/

[westwest888]

NGK OEM replacement plugs are what you should do. Don't change the temperature. If you want to go high end, you can replace the coil packs with Ignition Projects for $900 for a set of 6.
Sent from my Nokia 1520 using Tapatalk

[chaos2984]

If they changed manufacturer of the plug all together then audi didn't like what was going on. My guess was a lot of warranty for plugs was happening and even though audi probably wasn't paying for it they didn't wanted less warranty complaints. Either they wouldn't seat right like guy said that could leads towards them coming loose over time and cause other issues. Or they wouldn't last and need replacement under warranty and not as a cash job. NGK are just better all around plugs in general i believe.

[SwankPeRFection]

if you are tuned, you should consider going one step colder for whatever plug you plan on running.

also, keep to the manufacturer guidelines, slightly off topic, but in the subie world, (and I am sure I will get my companies mixed up but) if OEM called for NGK, and you ran bosch, you would see issues with the install of the bosch due to the washers they used....you had to be oddly specific with plugs and oil filters for subies, but I don't think audi has that issue.

Black Tokio Roki oil filter FTMFW bro! I had a stockpile of them and when I ran out, it was time to trade it in anyway.

[mr shickadance]

i thought the subie OEM filter was best? i ran a K&N oil filter which sprung a nice leak on me, and again, I was told by the service tech that subie didn't like non-OEM oil filters, i left that out because I think service techs don't really know what they are talking about/are more likely to push OEM over anything else but the sparkplug thing came from EFI Logics, I think they know their shit forwards backwards and diagonal.

[SwankPeRFection]

You obviously weren't around the Subaru WRX/STI world when it first came over to the US then. Originally back in the mid 2000's, Subaru used Japanese made oil filters from a company called Tokyo Roki. They were the best filter hands down. Then they tried some crap white ones that leaked. Then as the newer model cars came around, they went with the other crap blue ones. Nothing came close to the originals and everyone would kill to get their hands on them. Here's a pic.

[audistealth]

Is that *your* kitchen counter? Think you have enough of those filters (19)? LOL

[integroid]

i thought the subie OEM filter was best? i ran a K&N oil filter which sprung a nice leak on me, and again, I was told by the service tech that subie didn't like non-OEM oil filters, i left that out because I think service techs don't really know what they are talking about/are more likely to push OEM over anything else but the sparkplug thing came from EFI Logics, I think they know their shit forwards backwards and diagonal.

The Black Tokyo Roki was the OEM made in Japan oil filter from Subaru. They later cheaped out in the US for the H4 motors and started selling a blue filter made by fram. Once they did that I started using the Black Tokyo Roki H6 filters since they were still importing those and they fit the H4 motors even though they were twice as big.

[mr shickadance]

getting back on subject, because it kind of surprises me that no one on here has even experimented with colder plugs.

I have not really seen a counter point towards not running colder plugs other than "the tuners have not said to run colder plugs"

I am not trying to be a smart ass, but only trying to invoke some actual discussion on the matter, I brought my side to the table, which condensed is basically, you are asking more of your engine, your engine in turn is going to run a little leaner, a little hotter, and in efforts to curb pre-ignition, running a step colder seems like a decent/worthwhile idea.

thoughts?

[westwest888]

getting back on subject, because it kind of surprises me that no one on here has even experimented with colder plugs.

I have not really seen a counter point towards not running colder plugs other than "the tuners have not said to run colder plugs"

I am not trying to be a smart ass, but only trying to invoke some actual discussion on the matter, I brought my side to the table, which condensed is basically, you are asking more of your engine, your engine in turn is going to run a little leaner, a little hotter, and in efforts to curb pre-ignition, running a step colder seems like a decent/worthwhile idea.

thoughts?

I went down this line of inquiry also and I think one issue (among many) is the service interval would fall to like 10,000 miles from 60,000 (or 40,000 if you're tuned).

[mr shickadance]

I went down this line of inquiry also and I think one issue (among many) is the service interval would fall to like 10,000 miles from 60,000 (or 40,000 if you're tuned).

english please?

[saxon]

I run the standard ngk plugs

After pulling them the heat range was perfect with no signs of detonation, no need to go with a colder plug

[audistealth]

I run the standard ngk plugs

After pulling them the heat range was perfect with no signs of detonation, no need to go with a colder plug

I've heard similar results here. Unless someone has observed otherwise on their stock plugs, with pics preferably, I'd leave it be.

[mr shickadance]

I run the standard ngk plugs

After pulling them the heat range was perfect with no signs of detonation, no need to go with a colder plug

Pics of plugs?

[saxon]

Pics of plugs?

Didn't take any, I will take them out soon to see how they are responding to meth

[Vogz]

getting back on subject, because it kind of surprises me that no one on here has even experimented with colder plugs.

I have not really seen a counter point towards not running colder plugs other than "the tuners have not said to run colder plugs"

I am not trying to be a smart ass, but only trying to invoke some actual discussion on the matter, I brought my side to the table, which condensed is basically, you are asking more of your engine, your engine in turn is going to run a little leaner, a little hotter, and in efforts to curb pre-ignition, running a step colder seems like a decent/worthwhile idea.

thoughts?

No one is experimenting with colder plugs because no one has had any reason to. The 3.0TFSI engine isn't having any detonation or pre-ignition issues with a smaller pulley and a tune, so there isn't any reason to.

I run 1 step colder plugs in my Z and I have added over 300hp. That is a modification level in which colder plugs should be used.

Simply generating a bit more boost from the same supercharger that was installed from the factory is not.

There are no tuners out there on any platform that recommend colder plugs for a simple pulley drop.

[mr shickadance]

No one is experimenting with colder plugs because no one has had any reason to. The 3.0TFSI engine isn't having any detonation or pre-ignition issues with a smaller pulley and a tune, so there isn't any reason to.

I run 1 step colder plugs in my Z and I have added over 300hp. That is a modification level in which colder plugs should be used.

Simply generating a bit more boost from the same supercharger that was installed from the factory is not.

There are no tuners out there on any platform that recommend colder plugs for a simple pulley drop.

I disagree, and so does ngk and given the understanding of heat ranges it's not like it's a crazy idea to bring this subject to the table

[Vogz]

I disagree, and so does ngk and given the understanding of heat ranges it's not like it's a crazy idea to bring this subject to the table

Disagree all you want, it won't change the fact that colder plugs are simply unnecessary in this application. NGKs description is a very generic one and in theory sure it sounds good, but in practice, we are telling you why isn't not necessary. I also tried to tell you that it will negatively affect gas mileage and partial throttle combustion because cold plugs need more heat to clean carbon build up off of them. That's why you don't see manufacturers using the coldest plugs available in every application.

If people were melting holes in pistons, then colder plugs would be one of the many things that would have to change to continue pushing the performance envelope forward.

It's not a crazy idea, but we've already discussed it. Just let it go.

One of the things that many people don't think about when modifying cars is the more shit you change, the more chance you will have of problems or undesired consequences. Don't change something until there is evidence that it needs to be changed.

[SwankPeRFection]

Vogs is right in terms of drivability. If you go too cold, they'll foul up and cause a sputtering sensation on the first couple of power pulls after puttering around town.

The thing with colder plugs is that you need to pick a range that helps a bit to move additional heat from the combustion chamber to solve some detonation issues but doesn't pull so much that it causes them to foul up when idling or other non forceful driving conditions. Because of this, you will NEVER be able to use heat range change on plugs to solve your detonation issues. This is why usually, most tuners will correctly tune an engine for maximum output while maintaining a level of safety in direct relation to what is needed to maintain drivability when not pushing the car.

This is why you see drag cars and other purpose built cars run like crap when they're not just balls to the wall. You either tune for high output and sacrifice drivability or you tune for drivability and reliable output. You can't really have both in perfect mix, at least not a perfect level of both. Hope this makes sense to people.

[paul]

Just changed the plugs out today for factory NGKs. Car's at 55k, plugs may have been changed at ~33k when I bought it CPO. Looks pretty much perfect.