Originally Posted by bigmacmondayf250
Thats crazy cause they gained almost 100hp, almost 200 tq, and nearly doubled the MPG without touching the engine internals... Thats pretty awesome in my book.
In the August 2014 issue of Fourwheeler which had the five worst (sorry, I had said 10 earlier) projects in the magazine's history, they summarized the projects results as going from 4.6 to 8.9 mpg city and from 8.9 to 12.3 mpg highway. They go on to say that at 1999 fuel prices that would have taken 8-10 years to pay back the $4,822 investment. That's how they classify it as a bad project.
I said earlier that I'm not sure I'd agree with their assessment, and having done the math on it now, I'd say I disagree. To figure the payback you need to assume a price of gas, and what percentage of the driving is city and what is highway. Picking $1.50/gallon (my recollection of 1999 gas prices) and a 50/50 mix of city/highway gives a payback of 47,000 miles by my calculations. I'd call that a 3-4 year payback rather than a, 8-10 year payback, and I'd say that's pretty darn good for any attempt to gain mileage.
Changing the driving mix to 25% city / 75% highway stretches the payback out to about 65,000 miles, so that's maybe getting iffy as a reasonable investment. But then again, gas didn't stay at $1.50/gallon for that long after 1999, so that improves the payback too.
Anyway, Brad's comment about the believability of the results aside, I certainly wouldn't stack this up as one of Fourwheeler's 5 worst projects. It's got to rate better than Dr. Dooley!