i changed my stock plugs to Bosch Platinum +4 about 5000 miles ago, i don't seem to have a hesitation at high speeds, at least at 110 mph,. 2002 pro5 29k on the engine.

mcdaddy, you state to use NGK, which all my friends recommended after i installed my bosch's, would you use the IRIDIUM plugs??

 

If you can afford the NGK Iridium, Yes go for it...they are the best!

 

I only use NGK iridium plugs. If you are up to it, try a set of BKR5EIX-11. A fine center electrode is better than a copper-cored nickel one, because it offers improved ignitability. In other words, a smaller center electrode means less material is blocking the spark from the fuel kernal. This probably will not net you any horsepower, but it will improve idle quality and cold startability. This type of spark plug also requires less voltage to make a spark, which reduces the chances of flashover, fouling, and reduces gap erosion. Because our Proteges fire off of both sides of the coil, a single platinum or iridium plug will only last 30,000 miles. But, if you can find one, a plug with precious metal on both the CE and GE will last 100,000 miles in your car.