If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Better MPG with premium spark plugs?
I have an '87 CRX Si that runs great and gets the expected mpg. Will I
get better gas mileage with premium spark plugs and wires? Thanks, Greg |
Ads |
#2
|
|||
|
|||
Better MPG with premium spark plugs?
|
#4
|
|||
|
|||
Better MPG with premium spark plugs?
|
#5
|
|||
|
|||
Better MPG with premium spark plugs?
>From NGK Spark Plugs web site:
Frequently Asked Questions Q: How much of a performance improvement can I expect from changing plugs? A: A common misconception is that changing spark plugs will result in a large power increase. In most cases, removing even seriously worn out spark plugs will only result in very modest power gains, typically about 1-2% of total engine output. This could be even less for computer-controlled vehicles, primarily because most newer vehicles have more powerful ignition systems and the vehicle's computer can make adjustments so that vehicle operation seems smoother and more seamless. Many people think that simply supplying more spark to the firing tip can and will combust more fuel. What they don't understand is that most newer cars' engines are so efficient that they are already burning all of the available fuel. Simply adding more spark voltage can't burn more fuel because there is no more fuel to burn. When a stock or near-stock engine is given a fresh set of spark plugs, peak efficiency is restored. The power gains that come from this restored state of tune are usually minimal. Any company that tells you that their spark plug will provide significant gains in power in a stock or near-stock engine is making blanket statements that may not be supportable. |
#6
|
|||
|
|||
Better MPG with premium spark plugs?
|
#7
|
|||
|
|||
Better MPG with premium spark plugs?
|
#8
|
|||
|
|||
Better MPG with premium spark plugs?
|
#9
|
|||
|
|||
Better MPG with premium spark plugs?
In article > ,
jim beam > wrote: > wrote: > >>From NGK Spark Plugs web site: > > > > Frequently Asked Questions > > > > Q: How much of a performance improvement can I expect from changing > > plugs? > > > > A: A common misconception is that changing spark plugs will result in a > > large power increase. In most cases, removing even seriously worn out > > spark plugs will only result in very modest power gains, typically > > about 1-2% of total engine output. This could be even less for > > computer-controlled vehicles, primarily because most newer vehicles > > have more powerful ignition systems and the vehicle's computer can make > > adjustments so that vehicle operation seems smoother and more seamless. > > > > Many people think that simply supplying more spark to the firing tip > > can and will combust more fuel. What they don't understand is that most > > newer cars' engines are so efficient that they are already burning all > > of the available fuel. Simply adding more spark voltage can't burn more > > fuel because there is no more fuel to burn. > > eh? you're very confused. mixture ratios vary, and spark energy > requirements for complete combustion vary too, by over ten-fold. part > of the ability of the plug to deliver those energy requirements are > determined by things like electrode conductivity and morphology, i.e. > design. hence, different plugs /can/ affect power output. sheesh, go > to a library rather than regurgitate garbage off the net will you? Maybe you should check the total resistance of a modern ignition system. Between the coil, distributor resistor, resistor wires, and plug resistor you can easily end up with over 50000 Ohms. How does a 0.001 Ohm difference in the plug tip matter? It is true that the voltage needs vary vastly with compression and the electrode shape. I am unaware of any modern car that needs a pointed electrode to achieve a proper spark. They all have enough spare voltage and dv/dt to work with a plug that has been mildly worn to a dome. Also, modern low emission engines maintain the proper air/fuel ratio underneath the spark plug even when the rest of the chamber is lean. It's a valve and injector timing trick. |
#10
|
|||
|
|||
Better MPG with premium spark plugs?
Kevin McMurtrie wrote:
> Maybe you should check the total resistance of a modern ignition system. > Between the coil, distributor resistor, resistor wires, and plug > resistor you can easily end up with over 50000 Ohms. How does a 0.001 > Ohm difference in the plug tip matter? This is a very good point, however... > It is true that the voltage needs vary vastly with compression and the > electrode shape. Maybe I'm just being silly, but it seems to me that more voltage is simply better (within reason - if it's enough to breach the ceramic, that's a problem, but assuming that's not gonna happen...) You have two electrodes and an air gap. You need to generate enough voltage to cause a spark to jump that gap. The stronger the spark, the less likely it is that you'll get a misfire. The actual resistance may vary depending on the air/fuel mix floating through the gap at any given time, but in any event, you want a nice hot spark to ignite it: if the mix provides a higher resistance, you need more voltage to create the arc; if the resistance is lower, the arc may occur at a lower voltage and not be hot enough to ignite the mixture - either way, more voltage is better. I can't imagine any instance you'd actually want LESS voltage across the gap. > I am unaware of any modern car that needs a pointed > electrode to achieve a proper spark. They all have enough spare voltage > and dv/dt to work with a plug that has been mildly worn to a dome. True - the shape of the electrodes isn't as much a problem as having the electrode(s) wear down, thus increasing the gap excessively, or having deposits build up on them, thus decreasing the gap significantly, or adding "insulation" to them, thus reducing the spark efficiency. The spark plug is a pretty simple device, after all... its operation and design really hasn't changed that much in the last, oh, hundred years or so... --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 0609-3, 03/03/2006 Tested on: 3/4/2006 12:15:03 AM avast! - copyright (c) 1988-2005 ALWIL Software. http://www.avast.com |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Camaro spark plugs | Mike Walsh | Technology | 4 | January 5th 06 09:10 PM |
Spark Plugs -- Heavy load of light gray and black deposits | Jeff Strickland | Jeep | 2 | November 26th 05 08:59 PM |
Question Platium Spark Plugs | Jason | Honda | 20 | May 23rd 05 06:36 AM |
Opinion - Spark plugs for '98 3.0 Voyager | Ken Peterson | Chrysler | 24 | March 20th 05 02:04 AM |
spark plugs condition | newsgroup | Saturn | 2 | July 11th 04 09:08 PM |