Spark Plugs after turbocharging....?

[RickM]

Speaking of spark plugs, what are you guys using after slapping a BAE, Protomotive or home brew setup onto your 911? I don't recall seeing recommendations mentioned. Surely if the compression is being effectively raised one must go to a colder plug.

[sammyg2]

No change here, but IMO I'm not running enough boost to make a change necessary.
My plugs look OK after inspection, no signs of running too hot that I can see. If I were running under full boost all the time if might be different but my engine only sees boost for short periods of time.

[RickM]

Interesting. Do you know of a fomula to convert boost pressure into the effective compression ratio?

[sammyg2]

Here's some good ones, but you need to know the VE of the engine.
http://www.turbofast.com.au/javacalc.html