There's been some talk about spark plugs lately, so while we're on the subject I thought I'd throw this in.

My GP has 70k on it and I have noticed a drastic drop in my gas mileage (almost 100 miles a tank). I put in a K&N filter and it brought some of the mileage back.
If I were to change my plugs, should I also replace my wires? Is it necessary on a completly stock engine? My only desire is to get my gas mileage back. This is my commuting car that's good for about 650 miles a week. The gas bills are killing me.

If I were to replace the wires, what is recommended? I see the Taylor 8mm on Grand Prix Store, is it worth it?

Thanks for all your help on this and in the past.

FYI (not sure if this could help or not): My car blew out it's resistor and then the fuse panel in December, it sat around moving between 3 shops for 5 weeks until they figured out the problem. $650 later I get my car back and this is when my mileage fell. I don't know if this tells you guys anything or not, but I'm still trying to recover from this.

ok, Well my gas mileage was bad until i did the following...replace fuel filter, k&n filter, plugs, and wires. i bought those irridium plugs from grand prix store and I bought gm wires. My mileage went from around 18 to 20-22 and the car runs better. So I would give it a try.

adam
98 gtp

What kind of gas are you using? Just curious, cause I've been averaging about 24.7 (according to DIC). Before I replaced everything I was averaging 22.x mpg.

All I did was:

Replace Supercharger and Accessory Drive Belt
Flush/Fill Radiator
Replace 195 degree stat with 180 degree stat
Replace plug with Bosch Platinum
Replace Wires with Spiro 8mm from GP Store
Replace Filter element with regular Puralator
(and drilled a few extra holes on the stock airbox

Anyways, the effects on fuel economy was negligable. However, when I used Oxygenated gas (some of the stations here like to use blended fuels all year long, especially across the river in Portland), my fuel economy average drops to about 16-18mpg.

I stay away from 76 and Arco like the plague. I haven't used Arco since High school, but everytime I used to go to 76, I get crap for gas mileage, no matter what car I'm driving. I also avoid all gas stations that have a sticker on the pump saying "10% Ethenol, Blended, Oxygenated, etc"

I've been using Mobil Super+.

The ethanol gas is used for flex engines and I would never use it. My parents own a Mobil Station and they don't even know where you'd go about finding ethanol gas around New England.

I'm gonna go ahead and order the Taylor 8mm and get some new plugs.

Thanks for the reply.

Where did you drilled a few extra holes on the stock airbox? How big was the bit and got any pic of it??

I removed the airbox from the filter forward. Used some coathanger wire to clamp the filter to what's left of the housing cover. You can really hear the blower whine, sounds pretty cool.

at that point you might as well put a cone filter on,,,just the same or better
:rolleyes:

I had just bought the stock replacment K&N. When I was installing it, I thought there has to be an easier way to get airflow. I didn't want to go back and get a new filter or anything needed to install it. I just used what I had.

I know,,,but a cone would be better at that point

A few years ago, I remember somebody posted (on the old list) a web site, where they got crafty with their dremel and cut a series of slits on the airbox where the molded fins are. My brother "stole" my dremel so I started using a regular drill but it was a pain in the arse, so I'll probably go buy another dremel to do it right.

The guy guy who originally posted said that its a poor mans intake, cause he also has a 7" cone, and noticed about the same responsiveness and sound from the gutted airbox and the 7" cone.

He did it because it looked all stock, (the slits were on the side and back, hidden by the fenderwall).

I have over 100k miles, so couldn't give a crap if it looked stock. I had the stock airbox out, because I needed to move the coolant bottle to install my HIDs, and I was too lazy to install a cone, so I decided to gut the airbox... Yeah, it was probably more effort to gut the thing, than install a cone, but at least if you gut the box, and have the slits in the right places, and you also fiddle with the shield thingy on the fenderwall, the thing will suck cold air.

My next task will be to remove the U-Bend, possibly the resonator, and put nice tips on. Yeah, I could buy a full exhaust, but I'm too cheap/lazy