spark plug change =large mpg increase

[barr1340]

Thank you


---
I am here: http://maps.google.com/maps?ll=41.746028,-85.713748
Sent from my amazing iPhone4 using Tapatalk

[AVIDMOTION]

I took back my TR6 and replaced with close to stock-the TR5. I am done with Iridiums. Stock ones lasted 30,000, the extreme autolites lasted 35,000 but should have been replaced when I saw the big MPG drop about 5,000 miles ago. Literally it took 45 minutes beginning to end to replace the plugs, so every Spring I will just get new ones. Iridiums can last up to 100,000 miles, that being said, their true useful life is less then 30,000, by that time they lost 30 -50 % of their oomph. The copper gives its all for 10,000 miles, then they are junk too, but alot cheaper to replace. You can really feel a SOTP difference, more responsive, no bog, full midrange power right up to redline, and added MPG. Look I just sold myself!

[G8-4-Speed]

I had a set of XP5245 Autolite Xtreme Performance Spark Plugs gapped @ .040 , they are irridiums and should last 100,00 miles like the stock plugs. I got about 40,000 out of them. Though they seem to run fine, there was a slight miss at idle and no matter what I tried my MPG has been down. I pulled a plug and though they were nearly perfect tan, perhaps a little too light tan, but the top electrode -the "pad" was nearly gone or gone on plugs. The gap was avg .048 the largest being .052. Big difference from .040. I installed TR5 NGK's at .040. Idles perfect and a large immediate MPG increase! Went from 14-17 city and 19-21 highway(17.8 combined) to 18.7 city/26-31 highway/19.7 combined. All for 45 minutes work. I will change these every Spring or around 10,000 miles.

Computer control vehicles use resister style plugs to keep from getting voltage feedback on the ground side of the circuits. With all data being voltage based, you can shift O2's with a plug change. You should see my O2 scans when I run 3933 Autolite copper race plugs, it looks like someone stuck a vibrater on my O2's..With that said, if voltage bleeds to the ground side, it can offset O2's to read leaner and add fuel which will hurt gas mileage(were talking mV, nothing that will you will feel or shock you) . Thats the biggest problem with plugs. There is no magic, if it sparks, the fuel lights. The problem is in manufacturing and the resistance of the plug. I don't have an answer for the magic number, just know if you see interference, its going to have an effect.

[AVIDMOTION]

All my plugs have been resistor type plugs. All my cars have always done well with NGK plugs.

[SpeedRacerX]

OK, I am now confused.

I went to Pep Boys and they had the Iridiums (no), the platinum NGK TR5-BP, v-power something, and copper resistor NGK TR5 (with no designation after it). I think the copper TR5s were like $2.29 each. I did not see any TR5 with a designation of "NFL" after it.

avidmotion, did you just get the basic NGK TR5 for $2.29 each or did it say anything else??

Thx.

[I12XLR8]

Subscribed. I've got around 38000 miles on mine and was wondering when I should change the plugs...I guess I would go with the TR6 as I have LTH, 93 octane tune, and intake that GRRRR8 mentioned

[hayabusa160]

order them online at advanceautoparts. go on retailmenot.com and input coupon codes. click pick up in store.= profit

[AVIDMOTION]

they were NGK TR-5 resistor copper plugs. I had to order them and pick up next day. The TR6 was in stock, I had bought them but took them back to get the stock heat range since my other plugs ran perfect but were just wore out(Iridiums)

[SpeedRacerX]

they were NGK TR-5 resistor copper plugs. I had to order them and pick up next day. The TR6 was in stock, I had bought them but took them back to get the stock heat range since my other plugs ran perfect but were just wore out(Iridiums)

So we have similar mods. So TR5 & not TR6, right?


Sent from my SAMSUNG-SGH-I997 using Tapatalk

[AVIDMOTION]

Yes NGK TR5- these are stock heat range and pre-gapped with the correct gap of @.040.
The NGK TR6 are one heat range colder are also pre-gapped. When I pulled my plugs they were running perfect, the color was perfect, just the plug was wore out, especially the "pad" at the top was nearly erroded away. So I stayed with the stock heat range. And now my car is running the best ever(New tune from Vector hit the nail on the head this time!)
After plug change an immediate gain in MPG, no more miss at idle, no surges, much quieter too, immediately responsive and I am sure some power in there too!