i was wondering about the nippon denso Iridium plugs they make for our 7's. are there any real benefits of these, gas mileage? performance? they are 35$ each, which is damn expensive.

 

$35 Bucks each is alot of money for any sparkplug. Thats like 140 bucks for just purchasing plugs.

 

They're supposed to last alot longer and that's about it. If your car is stock or even mildly modded you should probably just stick with the stock NGK plugs. The only performance plugs available for our cars are different heat ranges.

 

35? I'm pretty sure I've seen them for lower, like maybe 10-20.

 

They simply last longer. Most longevity for your $$ is probably platinum plugs.

 

Where???

$35 a plug for iridium is normal or even cheap for a plug specificly for the rotary engine.

I use them on my leadings, the life is about 10 times what a conventional copper plug is, and 5 times a platinum plug (which never fire for crap in a Rotary anway.

And about a 5 hp increase when used with a CDI.

 

Are you sure that's not just the CDI alone? Got any dyno sheets?

 

yeah, I'll see if I can scan them in the next day or two

 

im using iridium leading plugs myself. engine definetly felt smoother up top after switching, but i cant claim any power gains more than a little blip on the "butt dyno."

however they realy do last very long. after about 8k miles they had virtualy no wear, whereas i would have completely chewed through a pair of standard ngk's in that time.

 

How many miles are we talking about when you say 10 times longer with a CDI? My CDI box eats plugs for breakfast. I usually change every other oil change, ie 5,000 miles. This past time I went twice as long, 10,000 miles. The CDI box is on the leadings only. At 5k miles, the plugs aren't too bad, but they are noticably worn down. At 10k miles, the center piece of the plug was worn to a tiny nub, and a spherical shaped crated was eaten out of the sides around it.

 

well I was burning through regular copper NGK plugs at 2-3K miles and I was getting about 5k (or oil change intervals) with NGK platinum plugs with a mallory CDI.

I have yet to see any sort of wear at all with about 12K miles on the Denso Iridium plugs.

 

I did not know my CDI box would wear the plugs. I guess that's why I they had alot more wear when I changed them early for a smog test (which I left the CDI box on for). So using them on the leading plugs is all that is needed?

 

NGK Platnum Lazer Plugs $7.00 @ Advance Auto With 1 Year No Questions Ask Warrenty
It Don't Get Much Better Than That !! Keep a Spare Set of Leading in The Spare Tire Cowl ..

 

and I said:

check your warranty... does not cover plugs that are worn out completly

 

Makes sense buddy, the CDI box ups the voltage many times over for a hotter spark, and at low revs even fires multiple sparks.

 

My friends and I all run the NGK Iridium IX (BR9EIX) plugs on our cars with great results. These are all modded cars, half bridge ported and/or 400whp+.

I also like the fact that the plug is gappable.

 

I have not used those before, but a gappable plug would be great for CDI systems

 

I am assuming you could reset the gap as they wear right?

 

well you actually will get your best HP increases if you could jump the gap up, to say .40, when you were setting it at .30-.35.

Of course that larger gap pretty much requires a CDI and good plug wires.

 

Yep, the stock gap on the NGK BR9EIX is .20. I run .30.

 

Well... After adding an MSD box and watching the stock NGK leading plugs get "hollowed out", you know what i mean?? after 2500 miles.... I think I'll try a set of these br9eix's in the leadings!!!


Wait.. the picture shows a plug with a TIP on it??????????? that can't be right.......

but.. sparkplugs.com has 'em for 7 each... applications liks a bunch of dirt bikes and snowmobiles... that sound right!!!!!!!

Somebody post a PIC of these BR9EIX's's!!!!!