What's up with Spark Plugs?
 

The Bosch W3DPO is $14.75! WOW! :eek: (sticker shock)

But they (PP) have the NGK which is $3.50 and the autolites and AC Delco ones are about $2.00. That is quite a price gap.

http://www.pelicanparts.com/catalog/shopcart/911M/POR_911M_ELignt_pg1.htm#item0

So what are you guys running?
What is so special about the Bosch that makes them so much more?
Do these fall under you get what you pay for thing?
How would the cheaper plugs affect engine performance?

I don't mind paying the 14.75 for the plugs, I just want to make sure they are worth it and not the same thing as a Autolite.

I am running the 3dpo for two reasons.. 1) I really didn't know of or trust anything out there as a comparision outside of what Porsche recommends for this vehicle 2) I browse ebay regularily and found a new set on ebay for 20 (by set I mean 6).

Hey Mark - This IS the only reason I will stick with the Bosch W3DPO plugs. But I'd like to know the reason/difference that makes them so much more. Not that it's an issue, but I'm just curious.

If recollection serves, the DPOs are true platinums, not just silly coated electrode standard cheapo plugs.

I've had the ceramic part of the plug come loose to the point of falling out of the metal housing on several NGK plugs, and one even sheared the hex part that the socket fits over from the threaded part. That was a joy to get out of the head blindly with a very large easy out down the bore of the plug body.

Air cooled boosted Porsche engines are a pretty rough environment compared to some engines, and in the long run you usually get what you pay for.

One way to feel good perhaps is if you don't need to buy 12 of them (twin plug)....

LOL, Well, I just twin plugged my motor, so YIPPPIE...Look what i have to look forward to?? !!!!!!!

Henry(Supertec) recommended these to me. He claims they have had good success with them and are what they are using, so these are what I have plugged in my engine when i fire it up.

These are the same plugs used in the Boxster S and 911 Turbo.

NGK BKR6EQUP or NGK BKR6EKUB

Look here:

http://www.pelicanparts.com/techarticles/rice_ramblings/rice_ramblings-4.htm

I use to run W3DPO's but found they were too cold for daily street use and would foul very quickly, so I went with a slightly warmer plug (W4CS) and they have been fine. Geoffrey over on Rennlist has used these on his modified track 930 for years with great success. MUCH cheaper than the DPO's too :eek:

Funny! But this was more what I was looking for. Good Post!

iamchappy - Good link

I'm wondering now about how running a slightly hotter plug like WydRyd W4CS or the Bosch FR6DTC (from iamchappy's link) mentioned would affect the overall performance. Cause it would give a more complete burn so would that actually increase performance a little, wouldn't it?

EDIT: Also, would the gap have to be adjusted to account for the hotter plug?

FWIW, I use Bosch FR5DTCs on my twin-plugged engine...
I tried NGK's and that lasted about 10 minutes before I let the car cool down and I pulled them out....

Brian

What were the NGK's that you felt were to hot.

Well, I run an aftermarket Crane HI-6 CDI unit, and therefore run a larger gap (0.035") as opposed to the factory 0.024" setting. Works fine for ~1.1bar.

Any more boost will require a smaller gap, such as 0.032", but remember, this is for aftermarket CDI's. If you are still running stock ignition, I wouldn't go much above the factory's recommendations :confused:

I use the bosch because they don't seem to foul up as easy . I live in the N.East and I start the car once a week with out going anywhere in the winter and the silverstones tend to foul out a little bit vs. the bosch.

Here's a Gap question for you guys. Out of the box those W3DP0 are .6mm. The owners manual says gap at .7mm. The old ones are at .6mm. So I'm thinking I may just to leave them at the .6mm. Besides how would you gap them cause the electrode is on the side instead of at the bottom. I don't want to mess up the spark plug.

This may seem like a dumb question, but I want to make sure they are right the first time.

Thought I'd throw this in the mix here as well... is there a performance difference between the W3DP and W3DPO.. the O is platinum, but does that mean you can't use the W3DP? They are much cheaper.

Well, I've been told W3CS and W4CS works fine in our cars too, so I doubt there's a performance difference going with W3DP's. I personally use W4CS and they perform well even at 1.1-1.2bar.

Wydryd,
Do you mean W4CS OR W4CC?
W4CC are sold on Pelican for $2.25 each.
Where W4CS are $6.50 each.
Which plug is best in terms of mileage expected?
From doing a little research I have been hearing that the race plug (W4CS) will wear alot sooner than the stock W3DPO plug. So I am not sure if there really is a benefit in going with them if they don;t last as long. Looking for your experience.
What is the expected life expectancy from the stock W3DPO plugs?
Anyone have a feel or experience with this?

thanks,
Fred

I've only started using the W4CS plugs and my car is a daily street driver, not a track car, so I don't really know what to expect in terms of life expectancy, sorry :(