I have a friend who installed the above plugs into his '97ish Dodge Ram and says they made a good improvement for towing.

I have a '91 F-150 and am pulling a 3-horse gooseneck. Looking for little things that will improve towing before I add exhaust, etc., and was wondering if anyone has experience with the above plugs and if the plugs made a good difference?

Thanks,
-Mike

 

No takers yet?? Just trying to keep the topic fresh a little longer.

 

I doubt that the plugs made a major difference unless the plugs he took out were the totally used up originals. Unless you run a blower or turbo you won't gain much with the fancy/expensive spark plugs.

-Jon

 

Sounds good--that is pretty much in line with what I expected.

Next question is in regards to Jacobs ignition systems. They market a couple different systems that might be useful--an RV kit and an offroad kit, both including their coil, ignition, and an "uphill" module that increases power on hills.

Question being, is a factory ignition with 93,000 miles on it likely to be nearing replacement time? Will the Jacobs kit offer any benefit over stock? My expectation would be that mileage doesn't improve dramatically, but power improves to a reasonable degree depending on how strong the engine is. Just looking for someone who has done the modification and can speak to results.

Thanks again,
-Mike

 

Mike,

I have a Jacobs Mileage Master on my '95. It's great. Increased power, especially low end. Mileage on average is up over 15%. My truck is a Supercab 4x4. When I got it I was lucky to see 13.5 MPG out of a tank. My miles are mostly around town. With the Jacobs the only time I see less than 15 mpg is when towing/hauling or in the winter with extended warm ups and winter gas formulas. My last tank I checked was 14.6 mpg with only about 25 miles on the highway.

IMO it's the best single mod I've done to the truck. I did the ignition before anything else and the improvement was clear even before the other mods. As a side note.... I bought this truck from my Dad when he was going to trade it. He drove it after the ignition install and said it ran better than it did when he bought it as a demo with low miles. He is generally one to be against anything that is not a factory part, but was impressed enough to cosider one for his new truck.


As for plugs, I've never tried the Rapid Fires. I have tried several types with my ignition and now run Champion truck plugs. I did try the Autolite Platinum plugs and they worked well. At the time I got some sluggish throttle response, but I was running a monster gap and I think this was the cause. I did notice that the truck came up to temp quicker, so I tend to think they produce a hotter spark. I will try them with a "normal" gap at my next plug change. With my Jacobs I run .065 gaps, even with non Platinum plugs.

 

Thanks for your reply... I'll consider the Jacobs unit, as it is a complete package for less than $400.

Not too bad.

Thanks,
Mike