3.2 SS Spark plug

[brads911sc]

I have a newly built 3.2 SS, Compression 9:5.1, single plug, large port heads, ITBs, MSD, gapped at 40.

I am running the Bosch WR5DC+ Spark Plug that is stock on the 3.0 (80-83).

The 84-89, 3.2 runs WR7DC+

What should I be using? switch out the 5's for 7's since its not a stock 3.0?

[DRACO A5OG]

7's on 3.2

[kerthunk]

I have a fresh 3.2SS as well, but using CIS. I was going to run the WR8DC+ since I had a '79, but Steve Weiner told me that they would be much too hot and he recommended that I go with the WR5DC+ instead.

[kinein]

which one is the turbo plug for the 930 heard it runs cooler i am running a supercharger setup i have read that should switch up too turbo plugs so which one are turbo plugs?

[FPB111]

Bosch higher number is hotter
NGK higher is colder

I would run the coldest plug that does not foul, hot plugs can hurt.

[kinein]

Originally Posted by FPB111

Bosch higher number is hotter
NGK higher is colder

I would run the coldest plug that does not foul, hot plugs can hurt.

enough said about that one........

[kinein]

so what ngk would you run?

[kerthunk]

Have you tried pulling the plugs to check for fouling?

[kinein]

i just bought this motor with 62k on it, ill be putting my supercharger on shortly in a couple of weeks....so i am tryin to get some fuel injectors replaced and cooler plugs to run

[T77911S]

Originally Posted by FPB111

Bosch higher number is hotter
NGK higher is colder

I would run the coldest plug that does not foul, hot plugs can hurt.

+1
always run the coldest plug you can.
the main reason for hotter plugs is the idle circuit, it is richer and needs the hotter plug to keep clean.

i ran a WR4 in my 2.7 as a test. the plug was black from idle and driving around town, but when i took a trip, 9 hours of leaner burn mid RPM's, the plug was clean and white/tan.

start with a cold plug (wr5), check them every 100 miles and see how they look.

[db_cooper]

Originally Posted by FPB111

Bosch higher number is hotter
NGK higher is colder

I would run the coldest plug that does not foul, hot plugs can hurt.

I did not know Porsche made a two stroke engine...love the two compression rings and no oil control ring..

[brads911sc]

Thanks All for the feedback. I have had no issues with my 5's. I just had realized that many with a 3.2 mention 7's so i didnt want to cause any harm by running a cooler plug. Ill keep the 5's unless I see an issue...

[Steve@Rennsport]

Keep the 5's.

[brads911sc]

Thanks Steve!

[KTL]

The annoying thing about heat range numbers is not only are they not consistent from brand to brand (like others said lower # is hot, higher # is cold in NGK speak, and vice versa in Bosch speak) but also the numbers don't directly correlate. For instance the NGK BP5ES or BP6ES is good for carbs. Well that sounds like a far cry from the Bosch 5, but it's not.

[Halm]

What gap would be recommended for the WR5DC+?

Thanks.

[stlrj]

Originally Posted by Halm

What gap would be recommended for the WR5DC+?

Thanks.

What kind of ignition wires are you running?

[Halm]

Originally Posted by stlrj

What kind of ignition wires are you running?

As far as I know, the wires are stock, or OEM style, as is the rest of the ignition system.

[stlrj]

Originally Posted by Halm

As far as I know, the wires are stock, or OEM style, as is the rest of the ignition system.

Stock wires=stock gap. ~0.028"-0.030"

[Halm]

Thanks!