Ok, i have had people tell me, run Denso, run NGK, and i noticed different tuners advocate different plugs. I also have heard from a 300ZX TT owner that denso's run hot, causing detonation? What are you guys' experiences? I am leaning toward the denso's. What can I expect with the new plugs? For mods i only have an air kit, and chip, but i am adding ram air and a 3lb pulley soon.


(When I say Denso, i mean the Denso Iridium (IT20's?) and the NGK TR5's)

 

All I know is that it is a pain in the *** changing them with either brand of plugs it took me 3 1/2 hours to change a friend of mine

 

I dont know about the Denso's running hot. I had the NGK #6s and then went to Denso's and got better Throttle Response & Idle....

 

00FireRide,

Good luck on getting a definitive answer on this one. I posted a pic of a TR5 to compare to a Denso but after repeated requests nobody would take a pic of the Denso to post.

The TR5 runs and idles great in my motor. The burn is good too. Here is an updated pic of them at WOT and daily driving. The WOT pic is #5 which is usually the leanest cylinder in most L's.

If you like what you see go to carquest and get a set. They usually have them on the shelf.

 

I say it was fear of what they might find. =)~


NGK TR6 plugs here. So far, so good . . . NGKs will cost less than $2 each from most local auto parts stores.

 

When I get mine in, I'll be happy to provide a pic or two. I'll run them a while first though. I don't mind saving the next guy a buck or two if they aren't worth it. For 4#s of boost on a dayly driver, either plug should be fine. The densos are the only plugs I've heard of to actually make power though.

 

Not according to MRBBQMAN who pulled out an old set of Splitfire's and put in new Denso's. The TR5's run very similiar to the Split's. I'm going in search of his post (the hard way).

 

I have been running tr6's for a couple of months now. I do run a 4" vacume/boost at all times. What I have noticed is that during warmup and general traffic driving to work, the vacume runs about 18 inchs once the truck warms up. The idle will have a slight miss. Once I get on it the first time, the vacume goes up to 18 1/2 or 19 implying that the plugs may be a little cold to deal with extended idle and warmup. I do like the added insurance for detonation.

Andy

 

Hey Chuck, your page is always getting better and better.

I always find something new when I go there. =)

 

The price will prob. make up my mind. 1.99 per NGK TR5 (i think this is the one I use (compared to TR6, since I have an air kit, ram air, and a chip - also soon to be 3lb pulley), compared to an 11.99 Denso. That's 10 bucks more a plug!

Full Set of NGK TR5's = $16.00!
Full Set of Denso IT20's = $96.00!

They can't be worth 80 bucks more than the NGK plug. ALSO, When I go to new performance plugs, what is the perf. difference in the truck? Better throttle response?

 

Here's that quote from MRBBQMAN.


P.S. Thanks FlashSVT. I have more to add but it's hard to find the time.

 

Here's another issue with not just conflicting opinions, but conflicting data as well. If the search function was working, you could find posts that claim better e/ts and an increase on the dyno. Throttle response improvement is another reported benefit. I should know by the end of the day.

 

I ran the stock plugs with 3lbs of boost thru 18,500 miles with no problems and a 12.791@106.59 1/4 mile.

When I went to a 5lber, I feared a too 'hot' plug so out with the old--in with the NGK BR7EFs(.040 gap). Man, I hope they're the 'right' ones for my L--I shudder at having to go thru 'that' again anytime soon. Mine is a daily driver too--'cold' plugs and a 160* 'stat may turn out to be too 'cold' to keep from fouling but, so-far, so-good. I've put about 1,000 miles on them and it runs clean--will pull #5(thanks Chuck) Sat and look at it under my 'glass'.

 

I've got about 2500 miles on my BR7EF's, and have not fouled them out yet. That does include lots of low speed stuff here on the LA freeways.

they ren well at the track when I first installed them. The TR6's showed signs of erosion, with the tips definitely getting hot.

Here's a look through my plug magnifier.