Champion 7440 Question

[Big Jon]

I went to my friendly local Chrysler dealer today and requested the Champion 7440 double platinum plugs so many seem to prefer. I ran a few errands & came back after 90 minutes & was told they put in the standard 440 plug, the 7440 was too long & could possibley burn a piston. Now MX5 says they work so thats good enough for me but they said they called Mother Chrysler & were told they couldn't use the 7440s because they are about an eighth of an inch longer. Whats up with this? Anybody else get this line from their dealer.

[MX-5]

Your dealer is not doing something right.

They ARE a direct cross.
It's now printed in the 2002 & newer Champion catalog as an optional plug.

The plug threads, seating area, and ceramic center are all the same as the copper counterparts.
Only the projected core nose, and the double platinum tips look different.

It's too easy for the uninformed to simply say "no".
They just aren't educated to the PT, like all of us on the forums.

I spent a year getting the #7440 plugs to market. Have them contact me if they need more info.

[Big Jon]

I forgot to mention this was the first plug change for my local dealer, they were being very careful which I can appreciate and I told them I'd pass on any further info I got. What are the benefits of the 7440? More efficient? Power? Economy? I'm not into racing but I want to be able to put my foot in it on a regular basis & still average close to 30 mpg. That's all I want. lol My drivetrain is stock except for my Airaid & I'm getting a Magnaflow muffler & I've started to use Mobil 1. I average a little over 25mpg which has only improved slightly over 30K miles. Anything besides a lighter foot to help my mileage?

[MX-5]

Originally posted by Big Jon
What are the benefits of the 7440? More efficient? Power? Economy?

From the Champion website:

The double platinum plugs are designed with triple seals, and tapered center and side electrodes for more efficient ignition. They feature superior erosion resistance and heat dissipation, and host a "projected core nose", which initiates the flame closer to the center of the combustion chamber and pistons. This has the affect of advancing the timing, which allows you to reduce the maximum indicated timing, while reducing detonation and improving throttle response."

[pingber]

Hey --- listen to MX-5 ... he knows what he's talking about... my dealer also said that the dp plugs were nothing but trouble and that they are longer ... they actually showed me (they ARE longer, but only on the ceramic portion) ... since the spark is closer to the combustion chamber, the flame front is better, thus smoothing out the explosion (right MX-5?).

I just put them in and I love them, what a difference (and remember to TORQUE! - LOL )

pingber

[pingber]

Here's some info from the Champion site about the proejcted core nose:

Projected Nose "Y" Gap
This gap style projects the spark an additional .060" into the combustion chamber for a total projection of .210", and providing there is sufficient clearance to valves and pistons, provides the ultimate in performance. Initiating the flame front closer to the center of the combustion chamber has a similar effect to advancing the timing. Therefore, maximum timing may be reduced which helps reduce the chance of detonation and provides superior part throttle response. A second valuable feature of this style is a "broader" heat range. The core nose is longer, providing a "hotter" plug at low speed which helps prevent fouling. As engine speed increases, the incoming air/fuel mixture flows across the tip of the core nose, providing charge cooling which effectively reduces heat range at higher engine speeds for increased pre-ignition and detonation protection.

---and btw, I checked a few plug sites and they all list the 7440 as a premium plug for the Cruiser.

pingber

[Rick in PA]

Sometimes dealers amaze me.

If you tell them you found some information on the internet, they get that look on their face.

Like no customer is intelligent enough to seperate the wheat from the chaff. Sure, there's BS on the internet, but we're big boys and girls, able to sort most of it out.

Maybe this dealer should spend some of his time on the internet.

The Champion 7440s work fine.

Sign me, another satisfied user.