NGK Iridium BPR7EIX

[nycplumber]

Happy Holidays !

I have a 1983 911SC, NGK Iridium BPR7EIX Good Spark Plugs to Use? Service Manual States to Use Bosch Platnium WR5DP, Please Help!


Thank You!

Rob

[tirwin]

I think NGK BPR7ES is the correct NGK plug.

[ganun]

Ive been using the Iridium you state for about 4 years, no issues and 15,000 miles.

[nycplumber]

Thanks !!!

[RSTarga]

That what I use too.
I think the WR5DP is a bit hotter plug than the BPR7

[69BahamaYellow]

A few years ago, I tested several types of spark plugs just by connecting them one at a time into one of my car's ignition wires and grounding the body of the plug to the fan housing. This way you can watch each plugs firing pattern.

All the plugs I tested showed virtually no difference in spark pattern, but the NGK Iridium EIX series produced a noticeably brighter and consistent spark, compared to the others. Fine wire plugs like these are the way to go, in my opinion.

[tirwin]

I thought there was a long standing recommendation to avoid anything other than copper (Bosch) or Nickel (NGK) plugs?

[bkreigsr]

The Bosch plugs that I pulled out of my '85 were NLA so Glenn at Pelican Parts recommended Bosch W-7-DSR for my track car. Three seasons later still running strong and starting on the first click.
FWIW, Bosch has a handy cross reference chart on their website. (includes recommended heat ranges)
Bill K

[RSTarga]

I would not put Bosch my lawnmower.
Even Mercedes uses NGK on the AMG models.

[Arne2]

Bosch Super or copper are fine, when/if available. Bosch platinum or other such are cr@p. If the Supers are NLA, I will use the plain NGK instead.

[T77911S]

Originally Posted by RSTarga

I would not put Bosch my lawnmower.
Even Mercedes uses NGK on the AMG models.

it depends on the plug.
the bosch platinums REALLY suck. this is from a definate improvement.
i had used plats in my mazda truck for many years. then one day i decided to try a cheaper plug. i think autolights maybe. the truck ran noticeabley better and my mileage went up 3-4 MPG.

the bosch copper supers are GREAT plugs.
looking at the spark is no test to really go by.

unless someone has a dyno to test them, i would run each type for 5k miles or so to compare, until a controlled test can really be run all else is jsut speculation.
even from me. i have always been told coppers in the old cars but i have never tested the iridiums. i laways ran copper in my 77s but i have been using copper or silver in my 930. no results yet but the coppers ran fine.

[tirwin]

Good info. I've had two sets of NGK BPR7ES with the MSD Streetfire and Clewett pkugs and so far no issues. Running .033 plug gap with the MSD. I could probably go up another .005 but haven't bothered.

[tobluforu]

There are a few older threads that JW commented on in regards to Iridium’s which kind of blew me away. He states that he uses them in mfi cars that foul, and when he switches the fouling goes away which is pretty interesting. I have never used them; use ngk 6's in my mfi and get dry fouling which doesn’t affect drivability at all. But I’m going to give them a shot next summer. In regards to a clean running engine, I would go cheap, NGK coppers.

[T77911S]

try one step hotter of a plug. if your AFR's are OK and your plugs are black, the center porcelain, then go hotter.
you have to check new plugs. hi mileage plugs may be grey.

i dont have the proof to say iridiiums dont work but i know coppers do, and if JW has said coppers dont foul were iridiums do, thats enough for me. its a matter of sticking to what you know works.

i just pulled coppers out of my 930.
the metal base was black but the center porcelain and ground strap were grey and clean, and this was after letting it idle a good bit before shutting off.

do some runs up to redline before pulling a enw plug.
look at the ground strap. you will see an "annealing" line on the strap. or you should. i have read that that is the timing line. if the line goes all the way to the base, your timing is too advanced. the line should be at the bend in the strap.
what happens is with more timing, it gets hotter in there. the hotter it gets the more the strap is heated thus the annealing line moves towards the base of the plug.

[tobluforu]

Originally Posted by T77911S

try one step hotter of a plug. if your AFR's are OK and your plugs are black, the center porcelain, then go hotter.
you have to check new plugs. hi mileage plugs may be grey.

i dont have the proof to say iridiiums dont work but i know coppers do, and if JW has said coppers dont foul were iridiums do, thats enough for me. its a matter of sticking to what you know works.

i just pulled coppers out of my 930.
the metal base was black but the center porcelain and ground strap were grey and clean, and this was after letting it idle a good bit before shutting off.

do some runs up to redline before pulling a enw plug.
look at the ground strap. you will see an "annealing" line on the strap. or you should. i have read that that is the timing line. if the line goes all the way to the base, your timing is too advanced. the line should be at the bend in the strap.
what happens is with more timing, it gets hotter in there. the hotter it gets the more the strap is heated thus the annealing line moves towards the base of the plug.

My post was kind of confusing, go figure. He states that using irdiums "fixed" the fouling of plugs on some of the MFI cars he has worked on.

[RSTarga]

The original plugs for the 2.2S, 2.4S and the RS were Bosch W265 P21. This were platinum plugs of very similar construction to the current BPR7EIX.
Bosch discontinued that type of platinum plug and brought in a much cheaper type, which did not work the same.

[ganun]

A couple of comments,
NGK recommend 6 not the colder 7 for the 3.2 engine
I had a bad valve seal that totally fouled the one plug but never misfired, amazing iridium performance.
The std iridium has EIX suffix and .031 gap
EIX-11 have .041 gap

[911pcars]

Spark plug opinions - everyone has one. Given the correct heat range, they all work. The main difference is longevity and cost. OEMs tend to use iridium and are platinum plugs due to their longer life and thus deferred replacement costs. However, they're more costly.

YMMV
Sherwood

[Whitecaspar]

Hi,
I use in my 1982 Targa ( Motorcode 930/16)
NGK Iridium BPR8EIX 6684
Tip from Seller - is this OK?

Greetings from Germany
Andreas

[Steve@Rennsport]

Originally Posted by Whitecaspar

Hi,
I use in my 1982 Targa ( Motorcode 930/16)
NGK Iridium BPR8EIX 6684
Tip from Seller - is this OK?

Greetings from Germany
Andreas

NGK 8's are pretty cold and would be best suited for high-speed Autobahn use. I would run 7's for city-highway driving.