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I've been having a problem at idle and cruise I've ignored long enough. All was well when i had hotter plugs in it, but my fuel trims swing back and forth depending on how long it idles or cruises. It makes it hard to dial in my tune and the computer has to work too much. Right now I have br7ef gapped at .027, I gapped them at .025 but pulled one yesterday and it was at .027 on a .99 gap gauge.
I called NGK told them what I had and I was recommended a tr6 or a tr7IX which are both projected tip plugs. The CTSV guys seem to like the TR7ix.
I was told if I mostly raced it, the tr6 or Br7ef would be my best choices, leaning more towards the 6 since i'm only running 14-15 psi. However, I mostly street drive the car, stop and go traffic. I drive it to work almost every day. With these plugs (br7ef) my gas mileage (dont laugh) is ****.
Its not hard to change plugs, so no big deal on that. Should I do the tr6 instead of the 7ix's? I feel like I could run the gap at .030 on the iridiums and maybe not foul them out as easy. the plugs I have now are nice and black. Thoughts? (ddnspyder and awesome auto....no beating me up lol)
BTW, I already have the set of iridium's.....just havent put them in yet.
I only run BR7EF's in my boosted stuff and never had any idle/fouling issues if the tune was good with no leaks. Personally I would never run a TR6 at 1 bar of boost on pump gas no meth. I also don't like projected tip plugs for boost.
i only run br7ef's in my boosted stuff and never had any idle/fouling issues if the tune was good with no leaks. Personally i would never run a tr6 at 1 bar of boost on pump gas no meth. I also don't like projected tip plugs for boost.
I run br7ef on my 4.8 procharged truck, 12psi . Had tr6 in it. Tuner buddy said change em and gap at .28 , I'll be damned if it didn't run a little "smoother" for lack ove better description.. but different set ups can like different things. It don't hurt to play with a couple different plug combinations just to see if you "feel" a difference. My .02 cents any way.
Ran br7efs in everything . Including my old turbo 4.8 car that my girlfriend drove 100 miles a day for like a year on. Never had any issues
My car runs as it is. drives good. Wife drove it to mississippi. However, the fuel trims swing positive or negative depending on the situation. Never did that until i went with a colder plug. Hell, when i went with the 7's originally it idled like **** and I had to retune it. I dunno but this seems more pronounced with the 5.3 as it has over a point less compression. Understand this, I'm very picky about certain ****. Yea, I could let it fly like this, but its just not right and it bothers me. Some people's tolerance level to what a street car is, is higher than mine. If I didnt tune my own stuff, i'd never know there was an issue, but because I do, I just want to correct it if I can.
I didnt tell the whole story for fear what might be said. But so be it. its running too rich at idle, the fuel consumption is twice what stock it. I dont think it should be that bad. The fumes should not burn my eyes (sometimes when it starts to cool the plug off too much) and smell stick to my clothes. I've adjusted eoit numerous times to get it as good as can be. it idles at 15.2 afr but the computer is having to work hard to keep it there. sometimes the fuel trims are 10.9% positive and sometimes they are 6-8% negative. if I try to correct it from where i have it set, it starts running like crap. Its not supposed to be like that. The cam I have has no overlap also, so It shouldn't stink this bad. Wife wont ride in it because of this. Fuel mileage is not so good either. If this were a race car, I'd care less. But like I said earlier on, I drive it just about every day. Just trying to get this little issue sorted.
Flock it, I'm gonna try them I have them so I might as well. If I get some timing retard I'll pull a degree or so out. right now I'm at 14-15 degree and never picked up knock yet. I bet it would take another degree or two but I didnt wanna push my luck. I guess the only way to know is to try it. Some combos they work, some they dont. I didnt realize they were a projected plug till they were in my possession. I was a victim of listening to the internet lol.
What you describe does NOT sound like the spark plugs fault. It sounds like either exhaust leaks or bad O2's. What happens when you run full time open loop? Does it go away? There are plenty of trim tables that can be adjusted for accounting for a modified engine like you have. Even if a hotter plug resolves the idle issue, its more bandaid than root cause and introduces far more serious issues at WOT.
I run the br7efs (proj tip) and they run fine-maybe you have an injector problem or something, or are getting a false reading off the 02 sensor. The fact that your mileage is bad means something isnt right, but try the 6's, strange things happen.
Br7ef. AFAIK even tho the numbers would have you think otherwise, there is no discernible difference in heat range between the br7ef and the tr6. One is projected tip and one is not. Maybe the projected tip could help drivability idk.
I ran 14-15psi on pump gas with a tr6 in 2008-2099 and never had a issue. Everyone did. It worked then and it will work now. But the br7ef is a better choice and that’s why everyone uses them now.
I wouldn’t use a iridium plug at all imo. But there is a ton of fast import guys that would argue against me on that. So maybe it would work great 🤷♂️
Br7ef. AFAIK even tho the numbers would have you think otherwise, there is no discernible difference in heat range between the br7ef and the tr6. One is projected tip and one is not. Maybe the projected tip could help drivability idk.
I ran 14-15psi on pump gas with a tr6 in 2008-2099 and never had a issue. Everyone did. It worked then and it will work now. But the br7ef is a better choice and that’s why everyone uses them now.
I wouldn’t use a iridium plug at all imo. But there is a ton of fast import guys that would argue against me on that. So maybe it would work great 🤷♂️
A tr6 and a br7 are not the same heat range. They make a projected tip 7 but it's still colder than a tr6. I am impressed that you've tested tr6s into the future though
What you describe does NOT sound like the spark plugs fault. It sounds like either exhaust leaks or bad O2's. What happens when you run full time open loop? Does it go away? There are plenty of trim tables that can be adjusted for accounting for a modified engine like you have. Even if a hotter plug resolves the idle issue, its more bandaid than root cause and introduces far more serious issues at WOT.
well honestly I thought it was the tune. I tried and tried to correct it. I changed the o2 modifiers (that make them slower to react and less sensitive) and that helped some. Changed one of the o2 sensors. So far that side is acting the same. I’ll change the other one maybe to tomorrow. I’ve checked for leaks. That’s one reason I put the passenger side manifold back on (I didn’t explain this in my other thread because I didn’t feel like mucking that thread up with it). The header had a very slight leak and now I hear no leak. I have copper gaskets on all my v band connections. There’s no evident leaks there either, I looked when I had it apart the other day. I did the best I could to rule out leaks.
I’ve jacked with the tune everyday going to work. And on the weekends. Here’s a plug from cyl 2
I changed the plugs. When I was riding around I was all gung-ho about posting my thoughts on them. Now I’m kinda apprehensive about it. But **** it.
I gapped at .030 15lbs boost in 3rd, 12 in second.
idle: noticeably better. It seems like it’s not “trying” or struggling to idle. Like there was a slight roughness to it. Not a cam roughness, but more (you’re gonna think I’m silly) like a roughness like something rubbing the body or frame. Which nothing is, and that roughness went away. I could get it to go away if I set my base timing at 22 degrees but then the idle would dip and the timing wasn’t in as much control.
driving: could be a placebo effect but it felt like it would cruise easier and the speed would stay steady easier. I saw 1-2 mpg higher on my dic (driver info center, get your mind out the gutter...) than I normally do. Trust me, I pay a lot of attention to it. At cruise it would usually say 19.1 and now it says 20.2-21.xx.
wot: well it was already a little rowdy so I can’t say. It definitely doesn’t feel slower at all. I did forget that last night I added 1 more degree of timing (15 total) at 5600rpm and up. It was normally 14 degree up to and past 5600. Well right at 5600 it was pulling 1 degree of spark. So I took that out and I didn’t see it anymore. My afr was 11.2 through the whole run pretty much.
trims. Well. You guys are gonna think I’m full of ****. So I’ll just post a pic. I wish o had a before pic, it would be positives and negatives up to 7% either way and at idle it would be 9%.
.... Even if a hotter plug resolves the idle issue, its more bandaid than root cause and introduces far more serious issues at WOT.
QFT...weather is great now so you didn't have any issues at WOT other than having to pull the 1 degree you added, which may not have knocked with the colder *** projected plug. You may have to revisit this in summer or hot lapping at the track.
QFT...weather is great now so you didn't have any issues at WOT other than having to pull the 1 degree you added, which may not have knocked with the colder *** projected plug. You may have to revisit this in summer or hot lapping at the track.
well that’s no big deal. I’m giving it 14 degrees at 15psi. Other motor would sometimes get knock at 12psi with 11 degrees and the other plugs. I also had two people in the car with me last night so that’s a little more load on things. I’ll take the better idle, no stink and better fuel mileage, more consistent tune over possibly losing a few hp. It’s in driving conditions far more than wot. Plus I’ll have a little shot of meth on it soon.
well that’s no big deal. I’m giving it 14 degrees at 15psi. Other motor would sometimes get knock at 12psi with 11 degrees and the other plugs. I also had two people in the car with me last night so that’s a little more load on things. I’ll take the better idle, no stink and better fuel mileage, more consistent tune over possibly losing a few hp. It’s in driving conditions far more than wot. Plus I’ll have a little shot of meth on it soon.
I don't run a non-projected colder plug for more HP, I run it to keep pre-ignition away, even at low boost. Getting a bad tank of gas or an accidental over boost etc. are all reasons to run a colder plug to keep the motor safe. I thought you were all about reliability and safety? But I agree, once you have the meth kit on your margin for safety goes up.
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Does anyone use TR7IX NGK plugs? 
