What type of spark plugs do I need?

pjo046 · 04-15-2010, 01:31 PM

Hi!

I am installing an Electromotive HPV 3b ignition on my engine. This is a wasted spark setup, basically the same as the newer TEC3, TEC3r etc.

My engine is a 3.0 Euro Carrera. It has 8.5:1 CR. It has 200hp stock, but with headers, no cat, electromotive ignition and bitz EFI I hope it will be close to 230hp.

What type of spark plugs should I run? I now have Beru plugs with a 0.4mm (.016") gap, and solid copper core. Do I need another type to run with the Electromotive?

I have searched, and I see that several recommends a gap of around .024 - .025" with the electromotive ignition. But when I look at the guidelines in the electromotive manual, it says as a guideline: .035" (0.9mm) for stock type low output, .031" (0.8mm) for High performance street, .027" (0.7mm) for Alcohol high compression and .023" (0.6 mm) for high power 75 to 115 HP per cylinder.

Thus based on these guidelines, .024" seems far to small. What am I missing here?

Can I regap the solid copper core plugs I have, or do I need some other type of spark plug? What plug (brand, type, heat range, gap) would be the best for my setup?

JohnJL · 04-15-2010, 06:40 PM

NGK BPR6 or BPR7 are a good start with a .8mm gap. Depends on your weather, engine condition, star alignment, etc.

pjo046 · 04-15-2010, 10:03 PM

What is the difference between those two plugs you mentioned?

I believe the engine condition is good. I bought the car one and a half year ago, and the seller said the engine had been rebuilt 25 000 miles earlier. I live in Norway, so the climate isn't very warm. I will only be driving the car during the summer season, so the temperatures it will see will mostly be between 8 and 25 degrees Celsius. As for star alignment, I'm not sure what that means?

Flieger · Flieger's Garage

Star alignment is a joke- as in astrology

. He means that everyone seems to have a unique opinion on spark plugs and everyone has a different set of driving conditions/style which necessitates a unique plug.

pjo046 · 04-16-2010, 07:10 AM

Gotcha.

I thought he meant something about a grounding pattern. Hehe.

pjo046 · 04-16-2010, 07:17 AM

I searched the net, and found several different NGK BPR types. For instance BPR6-EY, BPR6-EFS, BPR6-HS, BPR6-E etc. How do I know which type I need?

What is the difference between BPR6 and BPR7? Different heat range?

rnln · 04-16-2010, 08:33 AM

as you said, Different heat range? If I remember right, someone said the 7 is running cooler. I had both and feel no different.

Scooter · 04-16-2010, 08:47 AM

FYI: I've used both 6's and 7's in my 2.7 RS spec and have fouled more with the 6's than 7's. This was mostly in Texas, a little warmer than where I live now.

pjo046 · 04-16-2010, 08:59 AM

I thought the 7's were cooler than the 6's, but if so, shouldn't fouling occur with the 7's rather than with the 6's?

Are the BPR plugs iridium plug/resistor type? And, anyone knows what the difference is between the -E, -EYS, -HS etc? Maybe it has something to do with the size of the threads? If so, what is the correct one for a 3.0 Porsche engine?

Superman · 04-16-2010, 09:22 AM

NGK copper-core. Standard, factory gap.

pjo046 · 08:32 AM

What did you mean by that last post? That this is what you are using? Or that I should use such plugs with an electromotive ignition?

Edit: I got an answer from Richard Clewett;
"With the Electromotive ignitions you're better off with a basic plug. We typically use NGK plugs. The BPR6EY or the racing plug R5671A-7 are both good choices.
Set the gap to .75mm."