Recommended Spark Plugs for 2.2T with Webers and MSD?
 

What are the spark plug of choice for a 71 911 2.2T with Webers and an MSD?

Thanks,

Jason

Anyone?

Here is something on a 67. I would read on what plug range to use vs how you drive and then choose a heat range based on that. I would go no fancier than a $2 local sourced copper plug and my first bet is one range hotter than stock.

I am making this general recommendation from previous John Walker posts.

No gap over 40 thousandths unless you research.
http://forums.pelicanparts.com/porsche-911-technical-forum/447671-spark-plug-recs-67-normale.html

Here is the search page. Load something like "spark plug choice" or "hot vs cold plugs" in the keyword field and choose the 911 technical forum.

Numbers don't work in the keyword field.

Pelican Parts Technical BBS - Search Forums

The following is from my Technical web page:

Weber Carbs Technical


"The following spark plugs are recommended:
•NGK BP5ES for compression ratios up to 9.1:1
•NGK BP6ES for compression ratios above 9.1:1
•NGK BP7ES for competition applications
•Plugs gaps to be .040" when using CD ignition and 0.028" for coil ignition systems
Please note these are recommendations only and final plug selection and plug gap setting are to be determined by the end user for their specific application."

copper plugs.
run as cold a plug as you can that does not foul. so start with a cold plug and work towards a hotter one.

a plug is designed to operate in a certain temp range so that it can clean itself. if too cold, the plug will be black and sooty and can foul, if too hot, the plug tip can burn up, possible creating a hot spot for preignition.

Recently changed from the NGK copper to the Iridium in my 2.2 and it seems to both idle and run much smoother.