What plugs and gap are all you guys running? I have a standard 4-5 PSI Roush intercooled in my 2004 F150 and have gone through 2 sets of Autolite HTO plugs in 10K miles due to misfires. The tuner gapped them at 28 and I have seen threads of gaps from 45 to 32. All the COP's were brand new 2K miles ago.

I am thinking about NGK plugs. Obviously I am running one step "cooler" plug but I am thinking that these things suck???

Please advise.

 

HT0 plugs are excellent plugs. 10psi+ run .032 gap. 28 is way to small. For only 4-5 psi you could probably even run them at .035 gap. What brand coils do you run? Anything other then stock coils are garbage.

If your tuner put the gap at 28 I'd find a new tuner.

 

If you have a 5.4 3 valve, NGK doesn't make plugs for it.

Is it fouling or burning the HT0's? Gotta read the plugs.

What does your tuner think?

 

Gap them at .032

There aint but 2 options on plugs for a roushcharged 3 valve. The autolite ht0 and brisk racing plugs.

Sounds like a tune problem to me, or the gap is too small.

 

BWD coils from advance auto. I tested them all for continuity and they are all ok. I think the coils are fine. Tuner is Blow by Racing from Ocala, FL who is a Roush authorized tuner. We have struggled getting my truck tuned for 6 months. It now backfires under load. My A/f gauge is in the correct range 13.5 to 15.5 most of the time unless I nail it and it drops to 9-11 range. I think I may have too much timing? The plugs are on the reddish lean side. Not whitish..reddish. The truck runs "ok" but it is not near what it should be. And the backfiring tells me something is off. The phasers, VCT's and timing chain were all new when I put the charger on.

How much does the spark plug gap really matter? 28 or 35 is that a huge deal???

 

Your plug gap has a lot to do with horsepower as well as how efficent your fuel is being burnt. To small a gap will cost hp. To large of a gap can cause blow out under boost. I run my plugs at .035 without blowout issues. The HTO's last 10-15k in my truck. The Brisk were good for 8k. Your tuner may be an idiot no offense intened. Also being a Roush authorized tuner means nothing. It just means he bought in and sells the product. I am curious though. did the stock Roush tune give you problems or just the custom tuning? It seems to me after 6months any mechanical or electrical issue would be sorted out and this would be narrowed down to a tuning problem. Perhaps you can elighten us. Backfiring in the exhaust is a reault of running rich. This could be in the tune, bad o2 sensor, or the tiny spark gap you have not burning the mixture completely. First things first. Fresh set of plugs gapped at no amaller then .032. In fact running 5-6psi I would run .035 .037. You want your gap as large as possible without causing spark blow out.

Second I highly recommend you contact JDM or Troyer and get a tune emailed to you. Problem solved. Here's a link to JDM. They have a much quicker turn around time then Mike.
http://www.teamjdm.com/2007-2013-f-1...m-engineering/

 

Plugs are reddish? What brand of gas do you use?

 

BBR should know their **** but sounds like you got screwed. I dunno why theyd do a chain too but could be off by a few teeth on a cam. Gap is very important as to little wont ignite all the fuel.

Like twinscrewd said. Contact jdm and get a good tune. My jdm and vmp tunes are damn good. Quick turn around time too

 

BBR didn't do the chain and phasers. My local guys did before I installed the charger. The timing has been rechecked and is correct. I have 185 PSI compression on each cylinder too. I am running 93 octane with a 10% ethanol blend in it. I have tried octane booster too. I am fairly certain it's the tune. I contacted troyer on Friday but no response yet. I have heard good stuff about JDM too. I don't need a world beater just a good running truck that makes some power and drives good. I am running the 3.1 upper with the stock lightning caged lower (7.5") pulley. I am making 4-5 PSI.

Other mods are flex a lite efans, comp cams stage 1 blower grind cams, OBX long tubes (No cats), flowmaster 44 with duals out the rear. I realize I am losing a bit of boost due to the exhaust so I am willing to change the lower pulley too and go for 8-10 PSI. Also have 4.56 gears and 34.4 inch BFG's. I don't want to change the fuel pump etc...just good reliable tune and HP. Right now I have neither.

In regards to the spark plug gap of 28 not being wide enough to burn the fuel: I assume that could cause the 9-11wide band reading under WOT? It backfires and feels like no fuel is getting burned. Yet the gauge shows it is getting a lot of fuel.

Thanks for all the advice. I appreciate it. I am frustrated. I wanna drive my truck and get 12-14 MPG and blow past some unsuspecting guy who gets in my way.

I saw JDM charges $285 for one tune..I assume they tune it for free until it's right?

What does troyer charge?

I have the SCT XCAL3 tuner already.

 

Forget Troyer unless you have 6 months to wait for the tune.

 

I'm using the spark plugs that came with the Roush Supercharger, is it a good idea or should I change them?

Troyer told me that I'm running close to 10 PSI but I don't have any gauges to confirm

I haven't changed the plugs since February

 

Roush uses Autolite HTO but they gap them at 45. If you are not misfiring you are probably ok.

 

If this is the case and those plugs are only lasting 10-15k miles, what plugs come factory in 2008 Foose (which I have) or Harley Davidson trucks with roush and whipple supercharges respectively? I say this because those factory trucks still say that the spark plugs will last 100k miles.

 

I Have NGK in my procharged 2008 FX4. I have a late 2008 with different body style plugs and they make an NGK plug that I am very happy with. That's why I was asking about NGK for my 2004. I have had no issues with them for the first 7k miles. They make several heat ranges. I am running one colder range than stock.

 

99% sure it's these (see links below) I plan on giving these a try next go round. My current set of HT0's have 8,000 miles on them and are already missing and giving me lack luster performance. Not impressed with HT0's this time.

These links are the best pricing I've found including shipping. If someone finds a better deal please post a link. Thanks!

Model Year(s):2005-2008
Part Number(s): M-12405-3V0
http://www.levittownfordsupercenter....ld-p-1422.html

Model Year(s):2008 2009 2010
Part Number(s): M-12405-3V12MM
http://www.levittownfordsupercenter....ld-p-1529.html