Plugs

[appletonn]

Anyone tried Bosch Super 4 plugs out on their car and noticed a favourable difference?

My Dad uses these in a 924S and reports smoother running and more even tickover.

Just curious![]

 

[morris944s2john]

Not being funny, but if your plugs are worn out, just replacing them for new (correct) type will give smoother running and more even tickover.

 

[appletonn]

Not long fitted new standard plugs, but was wondering if anyone had tried anything different in their cars and seen any benefit.

 

[zcacogp]

Super 4's don't improve performance*, they just last longer. But, in my experience, the extra life is more than accounted for by the extra price. £/mile, bosch single electrode are better. (WR5DC+, I think.)


Oli.

* - They will improve performance if the old ones are knackered tho'.

 

[Neil Haughey]

Tried them in my S2 a few years back. Car runs smoother on new correct type plugs. Don't waste your money.

 

[simdel1]

I think so...but I would have assumed that the turbo would have had different plugs to mine (I have WR7DC too).

Oh happy birthday for last week by the way! Were you able to get your tax return sorted?

 

[Mike_Pollock]

All the single cam car take the same - S2s are different, not sure about S

 

[bmnelsc]

ORIGINAL: robwright

Are Bosch WR7DC the same as WR7DC+, which is what ECP are quoting for my Turbo. Might be a silly question.

I would take them as the same as the WR7DC Super Plus premium plug. Copper core plus some unpronounceable metal enhancement at the tip []

 

[bert gear]

the + was added a few years ago same plug only model to use different plugs is the S2

 

[zcacogp]

I think the + relates to whether there is a resistor in the plug.

As I understand it, there is a resistor in the leads as well (as part of the standard Porsche design) so whether or not there is another one in the plug makes no difference.

(This may be all wrong - I have never understood the logic of putting resistors in HT circuits, although it is meant to improve the performance of them ... shirt buttons, anyone?)


Oli.

 

[bert gear]

see below for details

http://www.boschsparkplugs.net/411_manufacturer.asp

 

[Frenchy]

Iridium is the stuff you mention....................sounds expensive and i do not know what it does, i can only imagine it is a very low resistance material ?

 

[zcacogp]

ORIGINAL: bert gear

see below for details

http://www.boschsparkplugs.net/411_manufacturer.asp

VERY interesting - thanks Bert. Bookmarked for future reference. (And shows I was wrong in my understanding and explanation of the +.)

James, I think iridium is used as it is very resistant to spark erosion; the tips don't wear out as quickly, making for a longer lasting plug. At least, that's how I always understood it - so could well be wrong (again!)


Oli.

 

[robwright]

Guys just came back to this as posted from my BB whilst in a disgusting work paid for Premier Inn whilst up to my eyes in coal at the Port Of tyne the other night and thought that it didn't go in and didn't appear in my subscribed threads or got any emails. Not being ignorant. Hate it when the OP never comes back to the thread [] Thanks for the replies and many thanks for the guide. No really I never knew that much about spark plugs before tonight []

 

[TTM]

I was running the Denso Iridium IW22 on the 2.5 engine with MaxHP chips at 18 psi and they did make a noticeable difference over the NGK BPR7ES most people run and recommend - throttle response was brisker, the engine felt smoother, quieter, with a "cleaner" idle.

The Bosch WR7DC are the standard plugs for a standard Turbo, and as you run MaxHP chips Rob I would suggest trying either the WR5DC, which are the standard plugs recommended for the S/S2, and are colder by 2 points.
The BPR7ES from NGK are the corresponding ones for the Bosch WR5DC - heat ranges work the opposite way between Bosch and NGK plugs.

Make sure you gap them to 0.7 mm too.