Spark Plug Gap

[Davet18]

I ordered plugs (Benu 14fgr-6KQU) for my 99 Carerra . When I received them the box indicated they are gapped to .7mm. The Porsche Service Information indicates that this plug should be gapped to 1.6mm. The Benu 14fr6 LDU should be gapped to .7mm.

Since I am new to Porsche plugs with multiple bottom electrodes, do you have to purchase the plugs with the correct gap or can the gap be changed. If they can be changed how do you measure the gap on this type of plug with multiple grounds (bottom electrodes). Is the gap still measured between the center electrode and the bottom electrodes or is it measured between the bottom electrode and the insulator?

Thanks in advance for the help.

Dave T

[1999Porsche911]

I ordered plugs (Benu 14fgr-6KQU) for my 99 Carerra . When I received them the box indicated they are gapped to .7mm. The Porsche Service Information indicates that this plug should be gapped to 1.6mm. The Benu 14fr6 LDU should be gapped to .7mm.

Since I am new to Porsche plugs with multiple bottom electrodes, do you have to purchase the plugs with the correct gap or can the gap be changed. If they can be changed how do you measure the gap on this type of plug with multiple grounds (bottom electrodes). Is the gap still measured between the center electrode and the bottom electrodes or is it measured between the bottom electrode and the insulator?

Thanks in advance for the help.

Dave T

.7 mm is fine. You would have trouble at high engine speeds if you gapped them to 1.6 mm, IF the engine would even start. Larger gap also increases radio interference. I gap mine to less than .6 mm. (.022)

No need to use the 4 electrode plugs. The 2 electrode NGK plugs work just as well.

Edited January 4, 2008 by 1999Porsche911

[Tool Pants]

I think you are mixing up different style plugs, but I'm a Boxster owner.

14 FR 7 LDU has 2 side electrodes. The gap is 0.8mm, plus or minus 0.1mm. This plug is used on the 1997-1999 2.5 liter Boxster. I did not think a 2 side electrode factory plug was used on the 996. This plug you can gap. but you should use the type of gauge in the picture.

14 FRG 6 KQU has 4 side electrodes. I know this plug because it is used in 2000-2004 Boxsters. The gap is 1.6mm. I have no clue how you would measure the gap on this style plug. The mechanics at the local dealership don't gap them. They are good to use out of the box unless they have been dropped on the ground.

In the second picture you can see the difference between the two style plugs, and that is why the gap specs are different.

[p0rsch3]

'02 996 C2 here-

Anyone know what the de-facto recommended plug gap is for '02+ 3.6L ?

Looking at NGK, Autolite, Delco and most 'off the shelf' plug brands for MY02 996, they come gapped at 0.032" (.82mm).

Bosch has a "fixed gap" and does not say on the box.

I'm seeing 1.6mm suggested in a prev post concerning the Bosch plugs, which is 0.063" and a substantially larger gap.

My Pcar has about 34k miles on it so am going to change plugs. At what mileage/age should I be considering replacement of wires and coils?

Thanks in advance-

[1999Porsche911]

'02 996 C2 here-

Anyone know what the de-facto recommended plug gap is for '02+ 3.6L ?

Looking at NGK, Autolite, Delco and most 'off the shelf' plug brands for MY02 996, they come gapped at 0.032" (.82mm).

Bosch has a "fixed gap" and does not say on the box.

I'm seeing 1.6mm suggested in a prev post concerning the Bosch plugs, which is 0.063" and a substantially larger gap.

My Pcar has about 34k miles on it so am going to change plugs. At what mileage/age should I be considering replacement of wires and coils?

Thanks in advance-

.032 is fine. .063 is way to big of a gap for your car. The Bosch Platinum 4's are the only plugs I know of that come with 1.6 mm gap. This is a compromise plug for longevity and performance. You do not need these.

Edited January 19, 2008 by 1999Porsche911