I read the owner's manual for the my 99 sc300 and it's telling me not to use the single tip spark plug but only use the twin-ground electrode-platinum tips.

My question is why when i go to autozone they only have the single tip? Also is it better to use the single or double as the manual instructed?

 

I think they mean don't use a single tipped Platinum spark plug, since they wear out much faster then a dual tipped plug.

It is perfectly fine to use a single tipped iridium plug and even better to use a dual tipped iridium.

Correct me if I'm wrong but iridium is a stronger, more brittle metal so it takes longer for the electrical arch to wear down the electrode. That is why the gap between side electrode and center electrode in an iridium spark plug is much smaller.

I hope I helped you out.

 

So would u recommend the double or single ones?

 

dual tipped iridium are much more expensive, but if you're willing to pay then go for it! Otherwise the single tipped iridium will do just fine.

 

well is there any performance or benefit in using the double rather than the single? thanks again

 

Between single and dual tipped, there shouldn't be any performance difference. The dual tipped should just last a bit longer.

Here's something I posted in a different thread:

Iridium is the best way to go.

 

ok that clear a lot of things up, well ill just stick with iridium then thanks man