RangerDick

There has been some discussion about changing your spark plugs sooner when you have a tune on your car. Here are two pics of the plugs after 39,000 miles with a 1 bar tune. The gaps on the plugs have increased about 30% from stock. color is good. These plugs are the Beru brand and were in for 39,000 miles. Overall, they appear in decent shape. The only thing that caught my eye was the increase in gap. The car started fine and ran well. Hit 150 mph with no issues.

BauerR

The gap on my plugs definitely increased. Changed them @37000 miles because i developed a misfire after installing the Cobb tuner.

Carlo_Carrera

Those plugs look just okay to me. They look done.



This is what good plugs look like. 30k miles, no tune.

Macster

Actually they don't look all that good. The threads are discolored all the way up (or down) and the plugs should have been changed sooner.

Carlo_Carrera

Are you talking to me or the the OP?

993GT

all the plugs pictured in this thread look bad IMHO...I'd be aiming for half those mileage intervals

rmc1148

Agree, I changed mine at 13k miles and was surprised that while still within spec as far as gap they were in worse shape than I would have thought.

911 Rod

How does this effect performance/drivability etc?

Carlo_Carrera

My car ran perfectly with plugs that some here think look bad.

It is how plugs with 30k should look.

https://rennlist.com/forums/997-foru...condition.html

http://sharkwerks.com/porsche/997-tu...onversion.html