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Spark Plug Change Interval

For those of you that track your Boss, how often will you be changing plugs? The supplement calls for performing the 150,000 mile maintenance and multi-point inspection after track use. In the GT500 I changed them once a year but used iridium 100k mile plugs. They are a step colder than factory due to the higher boost levels I am running. Also, with the tune it dumps a lot more fuel in at WOT so the plugs will foul quicker.
 
I would think 50,000 would still be overkill for a street driver, maybe about right for a track car? (at least one that is not a dedicated track car) Best thing to do would be check one every 10,000.

The iridium plugs last a long time, I assume the Boss plugs are made with this but I have not looked at the part numbers yet.

If anyone cares it is an interesting read about this material. Some say the asteroid that killed the dinosaurs was made of this.

http://en.wikipedia.org/wiki/Iridium

The unusually high abundance of iridium in the clay layer at the K–T geologic boundary gave rise to the Alvarez hypothesis that the impact of a massive extraterrestrial object caused the extinction of dinosaurs and many other species 65 million years ago.
 
I hope we don't have the same issue with the Boss as I had with my F150. The owner's manual called for 100,000 but Ford found the plugs fusing to the head and recommended in a TSB to change every 30,000. This applied to the 2005-2007 3-valve/cylinder V-8. the dealer broke off 5 of my 8 plugs but luckily none were fused (this was at 73k). The kick in the pants is that the customer would have been charged nearly $300 per plug if drilling was required. :p
 

ArizonaBOSS

Because racecar.
Moderator
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The newer engines don't use those whack plugs that the 3V did initially. The plugs breaking off should not be a problem.

I certainly won't be changing them any sooner than once per year, and even that would be pretty lol.
 
ArizonaGT said:
I certainly won't be changing them any sooner than once per year, and even that would be pretty lol.
Modern cars can go a long time between changes. My HRC Odyssey went 105,000 miles before the first tuneup and plug change. ;D After the tuneup the car did not run any better and gas mileage did not change.
 
5 DOT 0 said:
Modern cars can go a long time between changes. My HRC Odyssey went 105,000 miles before the first tuneup and plug change. ;D After the tuneup the car did not run any better and gas mileage did not change.

That is why I think the 50K should be more then enough to change them out, sounds like a lot but I doubt you will see a difference by doing it sooner.

Thanks for the response on the truck, never heard of that problem. I had a 99 250 V10 with the plug blowing out problem. Checked it once a year to make sure it was OK and ungraded the plugs when I bought it so I never had the problem.
 
548
0
STIG302 said:
I hope we don't have the same issue with the Boss as I had with my F150. The owner's manual called for 100,000 but Ford found the plugs fusing to the head and recommended in a TSB to change every 30,000. This applied to the 2005-2007 3-valve/cylinder V-8. the dealer broke off 5 of my 8 plugs but luckily none were fused (this was at 73k). The kick in the pants is that the customer would have been charged nearly $300 per plug if drilling was required. :p
Thanks for the tip - I have a 2005 F-150 with the 5.4 3V. I just turned over 50K. Sounds like it might be time to switch out the plugs. ;)
 

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