Having 3.5L spark plugs in a 2.7L engine.

I have owned this my 2004 Dodge Intrepid SE, which has the 2.7L engine for about 55,000 miles and is now at 182,500 miles total. Well my car has been acting up a bit lately to where it seems to be misfiring so decided to change my spark plugs. Yesterday I went ahead and picked up Champion Platinum Power Spark Plugs(Part No. 3032) and was installing them as I noticed the spark plugs that have been in it this whole time were Bosch Platinum +2 Spark Plug(Part No. 4308). I looked up the 4308 spark plugs and found out through several sources that they are for the 3.5 NOT the 2.7. Not sure who serviced the car with the last owner or how long before I bought the car they were installed but I may have had these spark plugs running my car for 80,000 miles maybe more.

Unfortunately only 5 spark plugs can in my box of 6, so I'm needing to go get my missing spark plug from the auto parts store tonight after work.

Anyone know how it'll effect my economy or performance, or will it much at all? The 4308 is a quarter inch shorter then the correct spark plug.

You might need wires too. Make sure you have the right spark plug for the engine because too long of a plug can create disaster for the piston and heads. Too short will not fire correctly, as also the gaps are different. I'd double check the engine and get what manufacturers suggest for it. Usually I go by Champion for Dodge, Autolite for Fords and AC Delco for GM's. Good luck.