Spark Plugs Help

[denson]

I found two Bosch plugs that work for my 1970 911 S. They are W3DPO and W5DPO. I do not know which is better or correct for my car., The W3DPO I have and they are platinum. I am waiting to get the W5DPO plugs from Pelican. They stated that they are not platinum.

I have been told that I should not use platinum plugs in air-cooled Porsche's. Is that true? Should I stay with copper plugs?

So, do we go 5DPO or 3DPO? Platinum or copper?

Thanks for the help.

John

[Steve@Rennsport]

John,

The "DPO" designation tells you they are BOTH platinum plugs (old style). The new platinums are NOT to used in almost anything,...

3's are cold plugs and best suited for track use and high-speed driving. 5's are hotter and recommended for city usage.

You'll need to base your selection on the above information and I hope its useful.

[HarryD]

Steve,

While we are onthe subject of plugs. Which NGK would you suggest ofr Street with a bit of Autocross thrown in? I have some NGK BP5ES's on hand.

[mjmoran]

Steve,

While we are onthe subject of plugs. Which NGK would you suggest ofr Street with a bit of Autocross thrown in? I have some NGK BP5ES's on hand.

BP7ES for the NGK...

[denson]

Why not the NGK BP5ES?

If these work do they need to be gapped?

[Steve@Rennsport]

Why not the NGK BP5ES?

If these work do they need to be gapped?

BP5's are FAR too hot for any air-cooled engine.

[denson]

Steve:

Thanks for the help. I will us the Bosch 5's you recommended.

John