'73 S spark plugs

Anyone using other than stock spark plugs in their early 'S'? The stock recommendation is a W3DPO, but my car currently has W5DC plugs in it (recommended for a 'T'). I haven't had any problems with detonation using the hotter plugs from the 'T', so I'm concerned with going to the cooler plug recommended for my car.

I'm also considering using one on the alternate electrode design plugs; specifically the Bosch 3 electrode plug (W5DTC). I'm currently using a set of W7DTC plugs in my 914 and they made a difference in the idle quality and throttle response.

Anyone have experience with different plugs in an early 'S'?

I've heard recommendations all over the board for plugs used in the 2.4 S. The old Bosch platinum (original equipment ) number was W265P21. It's been switched to W3DPO. THe NGK catalog suggests NGK B8EV for the 2.4 S, but Ed Mayo has written that he's had great results with NGKB8ES. Gordon Ledbetter, the mechanic I trust most, and who also has a 911S, says W4CS by Bosch. That's what I'm currrently running, with great success. So, I'd think any of the above numbers would work well for you. Generally, the "hotter" you drive, the colder plug you want...I don't do track days anymore...

pwd72S is giving you good info. On my 72E, with MFI, I was running NGK BP6ES plugs until I cleared up the fouling problem then went to BP7ES plugs. Just remember with NGK, the higher the number the colder the plug.