924Board.org

[Rick MacLaren]

What's a good cold spark plug for the 931? Has anyone tried colder plugs? And if so, which ones?

[simsport]

I just melted a hole in a std piston running .8 bar and using wr7 bosch plugs, so I'd go colder than those suckers!

Simon

[John H]

I have used NGK plugs for the last 14 years and found that they have been the best you could find - I use a B8EV or B8ES and use the plantium type. These seem to work ok on the turbo from 0.8 bar boost right up to 1.1 bar.
I used the Bosch ones (WR7)a couple of times and found they didn't perform or last as long as the NGK.
I also tried some real fancy Champion ones but I had to buy (try)16 plugs till I found a set of four that ran all the time. Champion seemed to be having quality problems at the time and I've never used them since.

[Rick MacLaren]

Is it true that with the NGK the larger numbers indicate colder? And on others it's reversed?

[John H]

Correct a B8EV is colder than say a B7EV
if you go here it explains the meaning of the letters etc.
http://www.ngksparkplugs.com/techinfo/spark_plugs/partnumberkey.pdf
the advantage of these plugs (for me anyway) is they are the same as what I run in my old Suzuki 450 hence i have heaps of plugs around. Also between running the turbo and the Suzi I have yet to have a fouled plug.
I've had a few with no electrode but that's normally after a high milage.

I notice that on the NGK web site for the US they recommend a BP7ES or BP7EVX, whereas the Aussie site recommends a B8EV obviously the different fuels and emission controls have an effect on the recommended plug

[ This Message was edited by: John H on 2002-10-15 14:40 ]

[numbers]

I use the Bosch platinum WR6. It was recommended by a guy on the Bosch hot line.

[kris]

I noticed that the Porsche Specs recommend a hotter plug too. I was shopping for plugs today actually. I went with a colder plug myself after reading the post from Simon! OUCH!!! I ended up getting the NGK B8EV platinum plugs recommended by John. I Gapped them at .65mm. I havent actually gotten the car to run yet, so I cant say what performance will come from them yet. But they sound promising. They are about $4.50 each.....