Spark plugs Options

[ruddyboys]

Have to change spark plugs this weekend. I went to 3 FLAP and none of them carry Bosch W7CC. They have the usual AC Deelco, NGK, champion etc. Are any of these any good or should I stick to the Bosch? If Bosch is the best bet, who has the best price and shipping?
Thanks

[Rand]

I hope this isn't hijacking, but it reminds me of a question about twin plug engines. How does that really help? If multiple electrodes are a waste (which I agree with), why are multiple plugs effective? If it combusts, how does it matter where it started? Or how does it matter if it starts in more than one place (if that's even possible once it started)? It's in the same chamber and combustion is combustion, right? Sorry if it's a dumb question, but I've never heard the answer.

[Dave_Darling]

I hope this isn't hijacking, but it reminds me of a question about twin plug engines. How does that really help? If multiple electrodes are a waste (which I agree with), why are multiple plugs effective?

The whole charge does not just suddenly burn. It takes time for it to all burn. If you start the burn from two separate locations, the burn happens faster and in theory more evenly. The rule of thumb in 911 engines is that you can run a full point of compression higher in twin-plug engines than single-plug ones.

Modern cylinder head design makes twin-plugging less beneficial, as more care is taken to get the chamber shape to work optimally with the spark plug placement.

In some applications (e.g., aero engines) the two plugs are there for redundancy. Because if one spark fails while you're in the air, you really really really want to have another one there to light the charge.

--DD