dis1, save yourself some trouble and get NGK BKR9EIX plugs: they use the smaller (5/8" rather than 13/16") spark plug socket, so you don't need any special tools to install them. Unfortuneately, 9 was the coldest heat range available when I last checked.

-s-

they aren't the right length for FDs

run the Densos....trust me, I did the research on this: I called both NGK and Denso tech support, IRE01-27 is equivalent to the NGK 9 heat range

they are worth every penny

that plug is not designed for these cars

Densos go up to NGK 11 heat range

Do you have the part # for the denso's equivalant to ngk heat range 10 and 11? where do you order from? sparkplugs.com?

1) remove engine
2) change plugs with a socket wrench (righty tighty, lefty losy)
3) ***USE THE SEARCH FUNCTION***
4) reverse this proceedure for reassembly

http://www.densoiridium.com/faq.php

A good, general rule of thumb is to start with the factory recommended heat range. For every 75 to 100 hp you add to your engine, you may go to the next colder step. DENSO heat ranges move up as they get colder; 16 would be our hottest Iridium Power plug, 34 would be our coldest (ranges; 16,20,22,24,27,31,34)

10 is equivalent to 31

11 is equivalent to 34

yes, I ordered from sparkplugs.com

Improved_FD, I agree that the NGK BKR*EIX is not designed for use in a rotary, but there are quite a few people who've used them with no problems. I've personally put over 20k miles on plugs that weren't designed for my engine (used three sets of BR*EIX and/or BKR*EIX), and they work great.


The Densos do look very nice: I think that the platinum ground is a great idea. Still, it's tough for me to justify spending 5x the money on a set of spark plugs, no matter how good they are. I would need to get at least 30k miles out of the Densos for them to be worth it, will they last that long?

-s-

I tried the Denso racing plugs twice and didn't like them at all. They fouled really fast even though the heat range was about the same. My idle went to crap and I am sure I was loosing power too but who knows. For the money I'd say no way however the tip won't wear out like the standard NGKs. You could clean them and they would last much longer. If you want to try an Iridium plug I'd suggest the BR*EIX plugs. Many people have been using them and reporting great results.

If you want you injectors cleaned. try witchhunter.com ... I had all mine cleaned... they were pretty darn dirty when i had em out, i paid not too much anyways. Got em back like new. THey will also change the rubbers and clean everything for you. Pretty cheap too, check it out.

*shrugs*

they're working great for me....I'm not experiencing any of those issues

did you use the IRE series iridiums?

you got 20k miles out of each set of plugs or 3 sets?

I thinks your looking for the term "Drivers" left or right as this will never change no matter which side you sit on.

Yes, its all documented with pictures and such on my site.

cvs

yeah I remember this debate and I remember your site....I called bs/flawed on your testing then, and still do

I'll file my own report after 5,000 miles....I love these plugs, cleaned up my top end and I'm not seeing the fouling issues you described

I'm running IRE027

Just to get this thread back on topic...

If you have a stock or near-stock car, run the stock NGK 7's and 9's. They're easy to get, reasonably priced, and work great. Don't fool with fancy plugs until you get up in mods. But, if you're running a near-full exhaust, intake, and computer, I'd go with 9's all the way around.

That said, change the plugs from the top. Takes 30 seconds to remove the throttle body elbow, and they're not hard to get to at that point. I can change all my plugs in about 20 minutes. Going from underneath is pretty easy, but it adds quite a bit of time to drag out the jack and jackstands, get the car up and supported, etc. And, no, you don't have to replace any gaskets when you remove the TB elbow - it seals with an O-ring which is good for many removals and reinstalls.

Dale

Hey Improved FD,

Thanks for your comment however I take offence to calling my testing BS. Every car is different and my site and your comments are opinions. They are here for everybody to read, both sides. I'm not saying my words are law but you shouldn't put them down until you have a few more miles on your plugs and documented evidence of your results like I do. If you do the work that I did I'd be more than happy if you sent me your results with pictures and such and I'll post the info on my site as an alternative view on the subject. TIA

Rich, Please delete that post with the inaccurate spark plug info- Good thing I kept reading to see your correction!

I agree with Dale- change the plugs from the top. No need to be dramatic and jack the car up at all.

But I disagree that the throttlebody elbow needs to come off. I can easily just walk up to the FD and fit my arms down there with a normal 3/8" drive ratchet and take the plugs out in 5 minutes without removing the elbow. I have no idea why people describe it as a more terrible job than it actually is.

Same goes for coolant drain- just reach down the side of the block and unscrew the coolant block drain plug. The spark plugs are barely any worse than that.

If you want to easily and properly torque the plugs, you need to do from below.
And anti-seize is important. Even though my FD has re-positioned wiring and hosing,
still easier to do all from below.

Do as Chuck says, not as Dale. FB owner from 1983 - 1992. FD owner of 1 FD from 1992 till now.
Anything worth doing is worth doing correctly with love.

I do mine from the bottom. Easy

Torque is so low on plugs it's not like you need a torque wrench involved. I think spec is like 10-15 ft-lbs. Put your hand in the middle of the socket wrench, snug up tight. done.

Antisieze is a MUST, I have had to remove plugs with no antisieze and it's a bear. You don't need much, just a little dab. When you go to change they will break loose then come out by hand.

At the end of the day how you change it is personal preference. From the top or from the bottom, whatever works best for you.

Dale

Replace Plugs:


2 x BUR7EQP (Leading)
2 x BUR9EQP (Trailing)

Bam! While I prefer from underneath (with a lift) I agree with this. We need to argue about more important stuff...like what kind of oil is best.

Only for a stock car, Rob. If you have some bolt on mods and are running a little more boost, reach for heat range 9 in all four spots ;)

I recall reading somewhere, which I cannot find now, about needing a thin-walled socket to remove the spark plugs; is that the case? If so, where might I source such a device.

Thanks