E85 & Spark Plugs - What Is the Best Plug?
- Thread starter Hot Air
- Start date
Plug heat range has nothing to do with how quickly the fuel burns unless you pre ignite it. Its only to get hot enough to burn off carbon deposits that would otherwise foul the plug.
With e85 you don't have an issue with carbon but you do have an issue with pre-ignition. It is highly knock resistant, but not so resistant to pre ignition which is when a hot spot in the chamber ignites the fuel rather than the spark from the spark plug.
You want to run a colder plug with E85. I would suggest autolite 23's. As far as I know they are the coldest you can get with a widely available plug. I run them on gasoline and they work good enough for me.
With e85 you don't have an issue with carbon but you do have an issue with pre-ignition. It is highly knock resistant, but not so resistant to pre ignition which is when a hot spot in the chamber ignites the fuel rather than the spark from the spark plug.
You want to run a colder plug with E85. I would suggest autolite 23's. As far as I know they are the coldest you can get with a widely available plug. I run them on gasoline and they work good enough for me.
I was talking with a fellow racer who works for a ethanol co. here in Id. and he runs two bikes, a n/a Kawasaki and a turbo Harley, he runs e85 in the kawa and e100 in the Harley and uses a plug from a company called
Briskracing.com, check them out very interesting design and they do make them for our cars, they are located Houston, he beleives the plugs are made in Czechlesovokia,sp? We had a long talk on e85 and our cars, in his words,
go for it and add some timing and boost regarding my set up in my car, in his harley he runs 42lb's boost with no intercooler, but does use something similar to a 7th inj. to use as a cooling effect like a intercooler, very interesting, the harley runs in the 6's@200mph.
Ron
Briskracing.com, check them out very interesting design and they do make them for our cars, they are located Houston, he beleives the plugs are made in Czechlesovokia,sp? We had a long talk on e85 and our cars, in his words,
go for it and add some timing and boost regarding my set up in my car, in his harley he runs 42lb's boost with no intercooler, but does use something similar to a 7th inj. to use as a cooling effect like a intercooler, very interesting, the harley runs in the 6's@200mph.
Ron
Here is the link. Anyone got any direct experience with this plug in a TR?
Brisk Racing :: LGS SPARK PLUG
Conrad
Brisk Racing :: LGS SPARK PLUG
Conrad
Thanks alpha, I 'm not sure how to make the link to just click on it like you just did, I have done it in the past, but it happens when I hit some keys and just can't seem to duplicate it!! it is like I do it by accident and can not replicate it, WTF!!
Ron
Ron
If I'm not mistaken I believe the R42TS has the same heat range as the autolite 23. Autolites have a fatter ground strap (visible) and have a harder electrode material... this from what I have read from reliable sources.
You may want to double check the heat range cross reference.
You may want to double check the heat range cross reference.
Talked to the guys today at Brisk plugs, I will be trying a set of there silver
racing plug, part# HR14YS, the owner of the distibution center here in the US
says that I will be very pleased with this plug, seemed very knowledgable
about plugs. So we will see how they perform.
Ron
racing plug, part# HR14YS, the owner of the distibution center here in the US
says that I will be very pleased with this plug, seemed very knowledgable
about plugs. So we will see how they perform.
Ron
ethanolkaw
New Member
- Joined
- Dec 6, 2007
Hi All,
ronbuick convinced me to but into your ethanol conversations due to my own experiances. I am the guy that works for an ethanol producer in Idaho but that in itself does not qualify me as an ethanol expert, but, I have 7+ years experiance drag racing with ethanol. Sorry to correct you Ron but my current ride is a turbocharged Hilborn injected Kawasaki and my friend has the turbo H-D that runs 7.70's. My best so far on the Kawi is 7.06@200.5 wit a bunch left.
Thats about enough horn tooting, I feel I need to reply to some of your spark plug questions. With the boost levels you all seem to be using I would stay with the stock heat range unless you absolutely feel they are causing detonation(Highly unlikely).
There is absolutely no validity in E85 or blends causing preignition, there is no such thing as ANY pump gas that will out perform E85 in every aspect. By using ethanol you WILL decrease chances of preignition due to the increased MON+RON octane rating not to mention the superior latent heat of evaporation(Intake cooling effect). Which you all know is a big plus when the boost levels rise. I do not use an intercooler with 40 or more psi of boost, I inject fuel at the inlet of the turbo when boost reaches 20psi to produce the same effect as an intercooler. I could go on and on so if I can help in any way please feel free to ask
ronbuick convinced me to but into your ethanol conversations due to my own experiances. I am the guy that works for an ethanol producer in Idaho but that in itself does not qualify me as an ethanol expert, but, I have 7+ years experiance drag racing with ethanol. Sorry to correct you Ron but my current ride is a turbocharged Hilborn injected Kawasaki and my friend has the turbo H-D that runs 7.70's. My best so far on the Kawi is 7.06@200.5 wit a bunch left.
Thats about enough horn tooting, I feel I need to reply to some of your spark plug questions. With the boost levels you all seem to be using I would stay with the stock heat range unless you absolutely feel they are causing detonation(Highly unlikely).
There is absolutely no validity in E85 or blends causing preignition, there is no such thing as ANY pump gas that will out perform E85 in every aspect. By using ethanol you WILL decrease chances of preignition due to the increased MON+RON octane rating not to mention the superior latent heat of evaporation(Intake cooling effect). Which you all know is a big plus when the boost levels rise. I do not use an intercooler with 40 or more psi of boost, I inject fuel at the inlet of the turbo when boost reaches 20psi to produce the same effect as an intercooler. I could go on and on so if I can help in any way please feel free to ask
Well none of us are Ethanol experts here, not yet anyway
We appreicate your input of course. My understanding of the spark plugs to use is exactly what you said. This comes from my own experience and talking to other Turbo car owners ( WRX, EVO, ETC, ETC ) that have been using Ethanol for years. From a Turbobuick perspective ; use the plugs you would normally use at a particular boost level with 93, race gas or whatever.
A fellow TB guy was running 25 deg timing and 25 lbs of boost on the E-85, conservative tune. He used the same plug as he would use for his race gas setup. Results were astounding. Sorry guys he is not a member here :frown:
I'm running stock plugs in my now and have been for over a year with E-85
You are right, relative to pump gas you will reduce your tendency to pre ignite, however, compared to race fuel, ethanol has more of a pre ignition tendency due to its lower Motor Octane number.
It has a very high research octane number which is what makes high boost comparable to race fuel possible. While you can do that you must remember that the Motor Octane is less than the race fuel, so it will be more sensitive to pre ignition than the race fuel. This shouldn't be a problem if you don't have hot spots in the chamber, e.g. the correct heat range and type of spark plug. The plug itself can be a source of pre-ignition if not correctly chosen for the application.
VP 110 Gasoline as an example
MON 107
RON 113
E100 as an example
MON 102
RON 129
Of course true E85 is 15% 87 octane unleaded so the MON and RON rating would be even less. I couldn't find the RON and MON rating of e85 but fyi
87 Octane gasoline
MON 82
RON 92
So both the MON and the RON of the E100 would be reduced with the 15% mixture of 87 octane.
It would have a significantly lower MON rating than VP 110 but a higher RON. MON is a better test of a fuel's tendency to pre ignite than RON.
ethanolkaw
New Member
- Joined
- Dec 6, 2007
Pablo,
By the way the mon+ron octane rating of E85 is 103. Octane ratings are only one way to rate a fuels resistance to detonation. Alcohols excellent latent heat of evaporation in itself is a deterent to detonation that is not a factor of mon/ron. You also have to consider flash point and vapor pressure to compare apples to apples. Alcohol in comparison to Gas in any form is a more dificult fuel to ignite and this is why your ignition system must be up to the task. Go to any race fuel supplier and see the list of how many types of gas there are compared to how many types of alcohol. No matter what type of motor or induction an increase in static compression is needed to take advantage of the benifits of alcohol.
By the way the mon+ron octane rating of E85 is 103. Octane ratings are only one way to rate a fuels resistance to detonation. Alcohols excellent latent heat of evaporation in itself is a deterent to detonation that is not a factor of mon/ron. You also have to consider flash point and vapor pressure to compare apples to apples. Alcohol in comparison to Gas in any form is a more dificult fuel to ignite and this is why your ignition system must be up to the task. Go to any race fuel supplier and see the list of how many types of gas there are compared to how many types of alcohol. No matter what type of motor or induction an increase in static compression is needed to take advantage of the benifits of alcohol.
I am aware of the R+M/2 rating of E85, what I was looking for was what the R and the M were individually. Those are the RON and the MON, both different methods of testing fuel.
Yes alcohol has excellent latent heat of vaporization characteristics and this reduces the tendency to detonate, and pre ignite as well (because the fuel keeps hot spots cool, not because that characteristic increases pre ignition tolerance). You have to remember that detonation and pre-ignition are two different events. Detonation is when the spark plug initiates combustion and there is a spike, pre ignition is when the fuel is ignited by a hot spot in the chamber.
Because the RON and MON ratings are generated via a test engine, it would seem to me that the latent heat of vaporization would be accounted for (in the chamber) since you cannot remove that quality of the fuel for those tests.
anyway, to summarize; Take the two fuels, E85 and 110 Racing gasoline. Run them in an engine that has a localized hot spot that you have some external means of controlling the temperature on. You will find that the e85 will start to pre ignite with a lower temperature hot spot than the 110 will pre ignite.
Your point about latent heat of vaporization is good and this may prevent hot spots from getting that hot in the E85 engine. Thats assuming the fuel reaches that hot spot as a liquid. Once it is vaporized it is not going to absorb any more heat. Take for instance the ethanol hitting the intake port, some of it vaporizes, what doesn't, hits the back of the intake valve and vaporizes some more. As the valve opens some of the unvaporized fuel hits the cylinder ledge (exists on 3.8s) and vaporizes even more. At this point, how much of the unvaporized fuel is left? You may still need some to take away heat from the exhaust side cylinder ledge which can be a potential hot spot. Or any other hot spot. The cooling on the intake side may help to reduce the heat on that spot as heat travels to cool... but there is no uniform cooling of everything because of latent heat.
