I like the the densos, they feel good in my motor-nice idle, smooth accel etc...after I installed them, my a/f read leaner than my ngk 8s , I just compensated and put another 2% more fuel in my mafterburner which brought it back up....I really havent had problems ith any of my plugs..but I allways check them after a couple of blasts down the street and periodically Ill randomly pull 1 or 2 out and read them.....

 

When a plug goes toast because of one baby backfire or one hint of detonation and it cracks the porc, does NOT make it a superior plug. Denso's are flawed. Even if they were the same price, they would NOT be installed in my truck because they are the most unreliable, unforgiving and over rated plug on this earth. I ran Autolite Coppers in the cobra. Changed every oil change... I tried denso's once and they were ripped out after 600 miles. If plugs were as easy to change as they are on a cobra, i would still be running autolite coppers. $.84 a plug cant be beat.

NGK BR7Ef's are tough monsters.

Denso's go good with the other snake oil... Plasma Boosters.

 

What do mean flawed. The plugs may be delicate but they are far from flawed. They are a fine tuned plug. And when used properly will out perform any NGK out there. I have ran NGKs and they idle and misfire like *****. I have used two sets of IT20s and made sure they were gapped properly and they run real smooth. You can keep your autolites.

 

Cracked porc from one hint of detonation makes these plugs flawed.

I run BR7's and have very little misfire except at idle and even then, its just slight. Best to get back with your tuner or look up someone else to re-tune you if you run like **** with NGK's.

 

If you are detonating and it cracks the porclein isn't the plugs faults. Like I said it is a fine tune plug. If you are detonating then there is tuning problem. Your NGKs may handle the detonating better but it will not out perform the DENSOS. Yeah I would be pissed if I spent 70 bucks and ruin a couple because of detonation. But that does not make it a flawed plug because of tuning issues.

 

Well, i would like to believe that, but there is inaudiable detonation. You cant hear it. Also, try this with your denso's. Wind up your boost to about 19 psi.. Get on it to WOT , then lay off the throttle, hit it again with a WOT blast then inspect your plugs.

What proof do you have that Denso's outperform NGK's?

 

While I haven't gotten to 19psi yet. I am at 14psi and have done many WOT, shut down and WOT again and have never had cracked porclein on my IT20s with the plugs looking great. I have also run 4 hours straight at 100- 130 in 105 temp with WOT blasts in between recently, not on a dyno, and changed my plugs and plugs looked great. Now your inaudible detonation I haven't had that problem and from my dyno runs when there seemed to be a hiccup on my charts it was so so slight that it was nothing to really worry about if it even was detonation.
Now I am not going to debate with you if you are running platinums and I am running iridiums because iridium is a better material period over platinum. Also I will not debate you if you are running NGK iridiums because it will just run as good as DENSOS.
Iridium is stonger, handles heat better and conducts electricity better. But it is extremely expensive. And that is my proof because of my knowledge of materials. If you want proof go to any spark plug site that sells iridium plugs and it will show iridium is far better than platinum.
Now your problem with densos probably had a slight crack in the porclein before you even install it and the detonation took it out. But lets get this straight any loud or inaudible detonation will destroy any spark plug even your autolites. It is all in the tune
period. I have tried the platinum NGKs and did not like way it idles and missfires. I have yet to have that problem with densos.

 

Interesting. Where have you ran 4 hrs straight avging 100-130 mph with WOT blasts? Amazingly you werent stopped and arrested.

So i should go by the Denso chart and believe they are superior because they say so? OK, i just thought maybe you had some real factual data to back up that statement is all.

Why would $10 Denso's have a slight crack in them from the factory? I would suspect, for $80 a set, they would have far superior quality control on such a superior product

Which model NGK's were you running?

 

Check NGKs site also for their iridiums. They will tell you there better than the platinums. But I guess they don't make them for the lightnings but if they did I bet they would be used more than the platinums. But I forgot you would not use them because of the price. I have used the TR6s. Won't go back. And yes I was lucky but I also wanted to see what the truck can do under severe conditions. That was once in a lifetime I could not pass up. Roads were pretty clear coming from vegas to phoenix and not one officer on the roads.
Don't just go by Densos chart. Do you have any clue on how fragile the ceramic is. There is lots more material used in platinums which make them sturdier. You do not need to have a visible crack. It could be inside towards the electrode where heat is transfered. And I don't need actual facts to know iridium is far better than platinum because I already know. But it is obvious you don't know the facts. You need to do some research yourself on these materials. I will make a wager with you. My number is 480-945-7543. I have a paypal account my name is Scott. I will give you $60.00 If you can show proof that platinums are better than iridiums. This should give you some incentive since I am not asking anything in return. And remember I never said that NGK iridiums are better than DENSOS iridiums. This not NGK vs. DENSO it Platinum vs. iridium. You got a bum rap on your Densos. Also remember there have been a lot members that have toasted many NGKs

 

I think the only irid's NGK has out right now are TR5's for the L.. Way to hot for my setup. I run BR7's. Ill take a loss in power for safety. I know of people hitting 18+ PSI on TR6's

What i do know, Denso's have yet to prove their superiority when it comes down to hp to hp or ET to ET. Lots of guys who were running Denso's from the beginning of the year are going back to NGK's. I wonder why that it is. Ill take a slightly rougher idle for a stronger plug.

If you want to compare metal to metal, sure ill agree irid is stronger then platinum... however, if you want to compare the structural integrity of the electrodes on an NGK plug next to a Denso, you will lose that $$. Use the search button and pull down all the melted plug threads and check out those denso's...

 

Many were going back to NGKs for the price because their tunes were not right and did not want to keep shelling out the dollars. You can't tell me all of it was performance reasons. And think of all the ones that did switched to densos and shelled out the cash which tells me it is definite performance reasons. You want to talk about quality issues. I am talking about performance issues. Big difference. Many of the quality issues could be from the person gapping the plugs not the company. It doesn't take much on these small electrodes.

 

My take on this is that if you are running a built motor which allows you to run higher boost with some piece of mind, you are gonna need to replace your spark plugs no matter WHICH plug you are running. Higher boost levels ( 17-18 psi) beat the **** out of spark plugs.....good tune or not. In that case, you will need to replace your plugs 3 times a year IMHO. Are the Denso's worth that gnats *** in performance for an extra 60 bucks a plug change??

 

Well said.... Like you I changed my plugs all the time. I had 25,000 on my 01 when I got rid of her and she had 7 sets of plugs in that lifetime. Not that it needed them, just for that extra fuzzt feeling of safety.....




Maybe in a low boost or stock truck you can leave Denso's in for awhile. They did help my truck when I only had a 3lber, they just dont hold up with boost like NGK's do.

NGK's have been in 10 times the cars with high boost or nitrous and have a very low failure rate.

Besides, 4 sets of NGK's to 1 set of Denso's does not add up cost wise.

And try to find a Denso at a local Auto Parts store...

 

I have actual data by the sales and return of Denso Vs. NGK AZ you said maybe they had a bad plug out of hte box very likely I have sold many Denso that failed with little or no mile on them. NGK No defects what so ever Nata None period.I have sold thousands of both and NGK is the set it and forget plug bar none.I was disapointed with the Denso's I just expaceted more from a Japanses part.NGK is used for it durability and dependability why would anyone take a chance and paid 6 times more not me.And one last thing the br7 and tr6's are a copper core plug so is the iridium really better NO. But lets just leave it to this if you like Denso's and many are then good for you but I'll take the bullet proof NGK's
Jeff

 

Wouldn't that be about 2 hours of driving time at that speed?

For the best bang for the buck, the NGK wins. If you're just looking for the best plug regardless of cost, then get Densos. Biggest problem is availibility. There have been times on this forum that members were panicking because they needed to replace a plug(s) and could only mail order the Densos. To me the ease of availibility makes it more worthwhile going with NGK's.