I_am_imprezed

anyone use these? How much of an improvement over the SuperPlus'?

ZW 944

nothing. get some NGK copper plugs. then you will see an improvement, and also save some coin in the process. I don't remember the exact model plug, do a search, and you'll find which one your looking for. I believe its the #7 not #6 heat range.

onspeed

bpr7es is the one you're thinking of. part# 5534 at autozone/oreilly/advance

ZW 944

Those are the ones. they're like $1.50 compared to $5. I tried the Platinum 4+'s back before I knew much about cars. the fact that they have 4 posts doesn't make a stronger spark, it only increases the chances of a spark occuring. (which, provided that everything is good with your engine, will happen). Whereas the higher conductivity of copper compared to platinum will yield a better spark. Generally speaking its a tradeoff, platinum have longer life, but less power, and copper need to be replaced more often, but are better.

ernie9468

Don't worth it ,don't know witch year is your car or if it has any engine mods but you should go with (Bosche Super Plus copper core + yttrium). I had + 4 on my 968 and got rid of them,copper is a lot better sparks conductor then platinum.

beentherebaby

FWIW- Engine dyno testing that I have conducted shows there is zero power difference in sparkplugs.

What you may see is one sparkplug lasts longer or doesn't fuel/oil foul as quickly as another sparkplug - assuming that you are using the correct heat range sparkplug for your engine.

I have seen engines that had a slightly smoother idle with the OE sparkplug compared to a different brand sparkplug. This was a very minor difference and not a misfire. Driving the vehicles showed no difference at all.

One aspect of sparkplug choice that is of significance in many modded engines or early Porsches is firing voltage requirement. Some sparkplug designs like the Bosch Platinum +4 claim to require lower ignition voltage and achieve operating temp more quickly then conventional plugs. This may be a benefit in engines that tend to have weak ignitions (early Porsches) or poor AFRs, especially on cold start-up, (carbs or improper calibrated engines).

Multiple electrode sparkplugs provide more quality surface area for an arc to occur and this extends the life of the plug which wears in use. Take all the advertised claims with a grain of salt but understand that from a technical and practical stand point there are some advantages to certain sparkplug designs. Just don't expect any power increases because the dyno and race track shows zero gains when using the proper sprakplug/timing for a given application.

KuHL 951

Don't ever use one of those in a 951 or you run the risk of dropping a tip and scoring the bore. You have to remember these cars are over 25 years old and were designed for copper plugs. Copper plugs are cheaper and work much better than platinum with our ignition systems. Platinum is a very poor conductor compared to copper but tends to resist fouling better...tune your car right and copper is the best choice.

piperporsche180944

Dont buy them....

choinga

amen - go with copper. The NGK 7ES's are ideal for any car with slight modification. Do some searching - there are a ton of folks on here that use them.

I agree with the previous posters - these cars are 20+ years old now and although it's appealing to want to take advantage of the latest innovations in technology...sometimes (like this time), it's a bad thing and not a good thing.

951mcomm

All,

On the pass fender of our cars it tells you in the sticker what plugs to use in our cars. It is recommended that we use COPPER Plugs as they have less resistance than any other plugs such as platinum or iridium. Which means they give a better spark.

fwiw

beentherebaby

Due to lower resistance Bosch or similar silver electrode sparkplugs would have better electrical conductivity than copper sparkplugs - which would be good for the reasons I previously mentioned above. The electrode material is only one of many design considerations in sparkplugs however.

The electrical energy delivered to the sparkplug is what determines the spark quality not the material the electrode is made from, per se. Many/most auto makers use resistor sparkplugs to insure the ignition system peaks for maximum voltage across the electrodes. Lower sparkplug resistance via metal composition is not a primary objective and does not necessarily produce a better quality spark.

boston951

NGK is cheap and effective. Series 6 for stock to moderately modified and series 7 for the higher boost cars.

Buy a set for little money and score BIG on performance