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Fiesta ST Spark plug tech

pelotonracer2

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#1
Not sure if, when or where this has been covered on this forum but here's a little information about the plugs used in our FiSTs. Fords Part # 12405 cross references to BOTH the Ford Focus ST and Fiesta ST, however, Ford uses a sublet number (i.e. SP-525, SP-532 ect) for internal tracking (but the plugs are the same, physically.. same heat range, same thread). Also, Autolite cross references XP-5363 as the direct replacement for all applications that use Ford part # 12405 (SP-532 and SP-525 among others). Interestingly enough, my 2011 Mazdaspeed3 used a FoMoCo plug which cross references to Autolites XP-5364 (same plug as ours except one range hotter) and *I used* XP-5363 (same spark plug recommended for our car and the FoST) in my modified MS3 and they worked GREAT. I hope one day I will see an XP-5362 part number because that will be a colder plug for our car. [biggrin]
 


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pelotonracer2

pelotonracer2

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Thread Starter #2
So... if there is a colder plug option for the FoST, there is a colder plug option for us too. [rockon]
 


MKVIIST

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#3
Repped buddy, this is great information.

Aren't the XP-5363 used in the regular Fiestas too?
 


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pelotonracer2

pelotonracer2

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I'm wanting to go one range colder, indexing and modifying the electrode for a tad bit more performance and mpg. When I index, I never use shims, I just buy plugs in "bulk" find the four plugs (or 6 or 8 or 10.. or... lol) that will line up in the position I want in the combustion chamber. How you may ask? You will want to note the position of the plug where the electrode is "open" and mark the porcelain section of the plug with a permanent marker so it corresponds to that opening. Then do a marking on the plug socket and the top of the extension. Insert plug into socket so the line on the plug lines up with the line on the socket and then attach the socket marking line up with the line you made on the extension. This allows you to "see" where the open face of the electrode is pointing when it starts to tighten (squish the gasket) even when you can see the plug in the cylinder. No two plugs will tighten with the face of the electrode in the same position, so you just adjust the amount of turning to get the opening of the electrode pointed in the 4 o'clock or even the 5 o'clock position (slightly to the right and pointing towards the exhaust manifold). DO NOT over tighten (especially on aluminum cylinder head) to achieve proper positioning and do not under tighten where the plug could loosen and vibrate out. If you can't tighten it down and get the right position in the combustion chamber, try again with a new plug! I just tighten down a bit more or a bit less to find the right position, but you need to know the range of gasket squish. Most tuners index the plugs at the 6 o'clock position (or the opening of the plug electrode facing directly at the exhaust port). This is not optimal because the curved ground wire blocks the incoming air/fuel mixture before combustion and causes a restriction to proper flame front travel. Facing the electrode towards either the 4 or 5 o'clock position or 7 or 8 o'clock position exposes the entire spark to the mixture instead of the ground wire blocking the flow. Pointing the flame kernel towards the exhaust port typically produces a small 1-2% increase in power & torque but also can increase fuel economy in closed loop operation of up to 3-4%, which is significant (and can pay for itself over a short period of time in fuel savings). Other advantages are smoother idle characteristics & better throttle response. Some people prescribe to the theory that indexing plugs is a waste of time and effort but in my experience over the years, the small tweaks when added together, all add up to something tangible. [burnout]
 


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pelotonracer2

pelotonracer2

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Ground wire modification for spark plug electrode: This used to be one of my closest held secrets, but I am going to share it (because I've been sharing it for years now) lol. Want to expose the spark/flame kernel (to better flame front travel properties) so that you get a more complete burn of the air/fuel mixture? I file the ground wire electrode back 1-2mm so that it is slightly offset from the electrode. This allows better exposure, and actually throws the spark and flame front travel during initial burn of the mixture away AND outward which ultimately produces a more complete, hotter burn. Better combustion = better efficiency. Increased efficiency = more power and better mpg. A word of caution: Bending and filing the ground wire is not as easy as it seems. Some plugs are pre gapped and some plug manufacturers will recommend not altering the ground wire. I've been doing this mod for 22 years and have it perfected. When I am done with the plugs, they look factory. You want to use a GOOD plug gapping tool that will not put stress on the ground wire weld. The easiest way to accomplish this is straighten out the ground wire enough to file it back 1-3mm. I use a metal file or dremel tool. I recommend a file for beginners. For best results, you want to file back enough of the ground wire material so that it is not directly over the electrode, but slightly (.5mm or 1 mm) of to the side and the end result should have the ground wire perfectly curved (rounded). Once I get a set of colder plugs for my FiST, I will perform this mod to the new plugs (that are chosen for a perfect indexing in advance by numbering the plug to correspond with the plug cylinder hole). I'll take a few pictures so you'll have an idea how they should look. [:)]
 


Harvick

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#7
Pointing the flame kernel towards the exhaust port typically produces a small 1-2% increase in power & torque but also can increase fuel economy in closed loop operation of up to 3-4%, which is significant (and can pay for itself over a short period of time in fuel savings). Other advantages are smoother idle characteristics & better throttle response. Some people prescribe to the theory that indexing plugs is a waste of time and effort but in my experience over the years, the small tweaks when added together, all add up to something tangible.
Invaluable tips pelotonracer2, subscribed for more posts.
 


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#8
I'm wanting to go one range colder, indexing and modifying the electrode for a tad bit more performance and mpg. When I index, I never use shims, I just buy plugs in "bulk" find the four plugs (or 6 or 8 or 10.. or... lol) that will line up in the position I want in the combustion chamber. How you may ask? You will want to note the position of the plug where the electrode is "open" and mark the porcelain section of the plug with a permanent marker so it corresponds to that opening. Then do a marking on the plug socket and the top of the extension. Insert plug into socket so the line on the plug lines up with the line on the socket and then attach the socket marking line up with the line you made on the extension. This allows you to "see" where the open face of the electrode is pointing when it starts to tighten (squish the gasket) even when you can see the plug in the cylinder. No two plugs will tighten with the face of the electrode in the same position, so you just adjust the amount of turning to get the opening of the electrode pointed in the 4 o'clock or even the 5 o'clock position (slightly to the right and pointing towards the exhaust manifold). DO NOT over tighten (especially on aluminum cylinder head) to achieve proper positioning and do not under tighten where the plug could loosen and vibrate out. If you can't tighten it down and get the right position in the combustion chamber, try again with a new plug! I just tighten down a bit more or a bit less to find the right position, but you need to know the range of gasket squish. Most tuners index the plugs at the 6 o'clock position (or the opening of the plug electrode facing directly at the exhaust port). This is not optimal because the curved ground wire blocks the incoming air/fuel mixture before combustion and causes a restriction to proper flame front travel. Facing the electrode towards either the 4 or 5 o'clock position or 7 or 8 o'clock position exposes the entire spark to the mixture instead of the ground wire blocking the flow. Pointing the flame kernel towards the exhaust port typically produces a small 1-2% increase in power & torque but also can increase fuel economy in closed loop operation of up to 3-4%, which is significant (and can pay for itself over a short period of time in fuel savings). Other advantages are smoother idle characteristics & better throttle response. Some people prescribe to the theory that indexing plugs is a waste of time and effort but in my experience over the years, the small tweaks when added together, all add up to something tangible. [burnout]
Three pronged question: 1. What does installing a colder plug do? 2. Are you measuring the distance between the electrode and the ground wire with a caliper? 3. Do you ride bicycles in a group to reduce drag? [wave]
 


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pelotonracer2

pelotonracer2

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Three pronged question: 1. What does installing a colder plug do? 2. Are you measuring the distance between the electrode and the ground wire with a caliper? 3. Do you ride bicycles in a group to reduce drag? [wave]
1. Installing a colder plug reduces the chance of the plug getting hot enough to cause pre-ignition or detonation. A colder plug dissipates heat better than a hotter plug. You can tell the difference between heat range by looking down into the electrode and measuring the distance between the porcelain and the metal casing. More area (space) between the porcelain and casing, the hotter the heat range of the plug and the narrower that gap, the colder the plug is. Hotter plugs usually stay cleaner longer and have better durability (less chance of fouling) but also increase the chance of pinging once you increase timing advance and or boost (or both). A colder plug offers some insurance and makes the ecu less sensitive to knock sensor backing the advance when it thinks detonation is eminent. Colder plugs can also effect emissions and fuel economy as well.

2. Yes, having a quality feeler gauge or calipers is important.

3. Yes, Yes I do. But if there are say, 100 riders, I like to be in the top 10-15 spots of a peloton or echelon. You can save up to 35% energy riding in the middle of the peloton. [wink] Staying closer to the front helps reduce the yo-yo effect when there are accelerations or surges. Lots of time you will get spit off the back (dropped) if you have bad positioning because you are always having to work a lot harder to stay on someone's wheel. I normally sit in (draft in the main body of riders (ie: "peloton") until the last 700-800 meters of a race and then I use up any and all energy I have left in for a sprint finish (if I don't get dropped going up hill haha). Even during a sprint, you find the fastest rider and ride his wheel until almost the very end (make him do all the work and then at the last moment, come out of the draft and beat him to the line. Being physically gifted is only one aspect of road cycling. being smarter than the guy you are trying to beat is even more important. [like]
 


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pelotonracer2

pelotonracer2

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Ok, after some research (and some info passed on from another forum) using the Mazda MS3 as the application, I have found the following spark plugs that will work in our FiST that is one step colder than stock: Denso itv22 or NGK LTR7IX-11 [biggrin] I'm going to remove a plug from my car right now to get visual confirmation that it is the same. I'm going to order $100.00 worth of these plugs and try to get them indexed where I want them.
 


Perry

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#11
3. Yes, Yes I do. But if there are say, 100 riders, I like to be in the top 10-15 spots of a peloton or echelon. You can save up to 35% energy riding in the middle of the peloton. [wink] Staying closer to the front helps reduce the yo-yo effect when there are accelerations or surges. Lots of time you will get spit off the back (dropped) if you have bad positioning because you are always having to work a lot harder to stay on someone's wheel. I normally sit in (draft in the main body of riders (ie: "peloton") until the last 700-800 meters of a race and then I use up any and all energy I have left in for a sprint finish (if I don't get dropped going up hill haha). Even during a sprint, you find the fastest rider and ride his wheel until almost the very end (make him do all the work and then at the last moment, come out of the draft and beat him to the line. Being physically gifted is only one aspect of road cycling. being smarter than the guy you are trying to beat is even more important. [like]
This is probably extending us a bit further [offtopic], but . . . . As a rider (and once-upon-a-time amateur racer--lowly Cat 3 at best), please let me add one bit here, if I may: by riding up near the front, but not being the tip of the spear plowing through the wind, one also more often avoids the mayhem that occurs when someone goes down. The jostling and general wildness and sketchiness go up the further back in the peloton one goes. I earned my share of road rash, and only got as far as I did because I learned how to ride smart--my physical gifts were, it seems, obtained from the remainder bin during a post-Christmas sale. [:(] It came down to lung size--if I could only have gotten more air in, I coulda performed better. Hmmm, that sounds kinda familiar . . . . [idea]
 


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pelotonracer2

pelotonracer2

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This is probably extending us a bit further [offtopic], but . . . . As a rider (and once-upon-a-time amateur racer--lowly Cat 3 at best), please let me add one bit here, if I may: by riding up near the front, but not being the tip of the spear plowing through the wind, one also more often avoids the mayhem that occurs when someone goes down. The jostling and general wildness and sketchiness go up the further back in the peloton one goes. I earned my share of road rash, and only got as far as I did because I learned how to ride smart--my physical gifts were, it seems, obtained from the remainder bin during a post-Christmas sale. [:(] It came down to lung size--if I could only have gotten more air in, I coulda performed better. Hmmm, that sounds kinda familiar . . . . [idea]
Yeah definitely that too. LOL. I know all about that as I'm just a Cat 5 "sandbagger" (Cat 5 racing borderlines as psychotic as most of the riders have no idea what they are doing) since 2005 (have never asked for my upgrade because I only do a couple few races a year). However, when I'm on form I can hang with the big boys until the 120 pound climber types drop me on a longish climb. Hills are no problem, I can power up them with the best, but any extended climb and I will get dropped). At 175 pounds I can't hang with them fighting gravity but then again, they are no where to be found in a bunch sprint where I am at my best. hehe. Our team is mainly Cat 3s and 4s, although last year we had someone racing for us in the P-1-2 races. At 45, I'm too old to compete at that kind of level, although one day I wouldn't mind putting some hurt on the uber fast Masters classes LOL (some of those old dudes are stupid fast). I haven't really been doing much riding the last few years. For my first 4-5 years I averaged around 9,000-10,000 miles worth of volume per year and I think that burned me out. Now I'm lucky to get in 4,000 miles a year. Cycling is a great sport but like anything else, consistency is key. [xx(]
 


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pelotonracer2

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Thread Starter #13
Anyways.. where were we? Oh, that's right spark plugs. lol
 


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pelotonracer2

pelotonracer2

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Thread Starter #14
I pulled a plug out of my FiST and visually inspected it. It is indeed the same plug as is used in the MS3. This is good news as there are several 1 or 2 step colder options available.
 


rooSTer

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To go one step colder I would assume our options are copper only right?
 


Colin1337

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Soooo anyone have any new info on the spark plug front? I still want a colder plug, the only aftermarket plug I have seen was from pumaspeed. I think it was a Bosch iridium tipped plug, but couldn't track it down on Bosch's site
 


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