While I don't normally believe any fuel additive is much more than their way of prying money from your hands, this stuff really works!

I picked up a few bottles under the advice of a friend who swears by it and ran it through. 2 full tanks of it in-town, and 2 tanks as part of a 1000 mile round trip to New Mexico this weekend. Now this truck, it's a 2000 F150 with a 4.6 has always been temperamental and down on power. Mods have been a way to get lost power back, not really to make more.

Fuel mileage on it has ranged from 13-14.5 MPG in the city and 15-16 on the highway as recently of last week (yes, I ALWAYS calculate my mileage at fill-ups).

Well, after I ran 4 tanks of RXP Gas Kicker treated premium unleaded through it, my highway mileage SHOT up to 22-23 MPG! It hasn't got mileage like that EVER, not even when it was brand new! So I though it was some odd affect of the RXP on the O2 sensors or something, but the 23 MPG tank was without RXP and it was burned to fumes before fill-up. So after the RXP, the increase in mileage continued even after RXP use was discontinued.

The truck's mods.....

After a highway incident involving a block of concrete and the oil pan, the engine got rebuilt at 115k. New parts include forged pistons with 10-1 compression, a 30-over bore, fully machined block, PI heads, stock cams (stock 2003 junk yard doner truck), deflashed intake, heads/intake gasket matched, stock injectors, dyno tune (budy owns a dyno, free=free) stock tranny, stock 3.55 rear gears, oil & tranny coolers, LT headers, custom y pipe with hi-flows, 3" back to dumped flowmaster sido, K&N intake etc. etc. etc

It's basically stock with only a few small optimizing improvements and about 500 pounds of audio equipment. It only dyno'd at 217/243. Any 2001 and up 4.6 with some basic mods would run about the same, might not sound as good, but still perform pretty close. Plus, none of these mods are new, they've been on the truck for some time now. So I doubt it's related. It got s**tty mileage before and after. The only thing that changed was the additive.

What's more, it has always run very lopy on cold starts for about 10 seconds, just like it needs plugs. It's done that since it had about 40k miles on it, and it started again about a year after the rebuild. That's gone now. And it's got POWER again! The power went in the crapper after about 2002. And started signing off again not long after the new motor went in. No doubt due to the INSANE carbon buildup that happens FAST in these 4.6's. Well, NOT ANY MORE! And the mileage, hell yeah! I'll take that!

I ran about 1.5 bottles of RXP per tank. It's not the cheapest, at $6.99 each, but IT WORKS!

Go pick some up, they sell it at Autozone.

 

So whats the deal witht his stuff? Anyone else have success with fuel additives? The only thing I have used is some gumout injector cleaner. I know the V8s are subject to alot of buildup, and didn't know if anyone else had success with some type of fuel additive.

Triton, did you continue to run premium even after you used the RXP?

 

I run a base timing of 14 degrees and 10-1 compression, so, yeah.

 

TTT

You guys should really look into this stuff!

 

acetone will do the same thing.. but u get 1 quart for about 4 bucks

 

also how the heck do u have that much done to ur truck and still on stock 19lb injectors?. i maxed out my injectors with just basic bolt ons. no tune, only major stuff was ported intake manifold and headers.

 

I am raising the BS flag on this one. There is absolutely no way that some miracle additive is giving you a 60% increase in mileage.

And the acetone myth has been disproved as well - SPOBI!!!

 

+1000 I don't see it happening like that. If it was that good they could charge 3 times the price and still not keep it on the shelf.

 

Hey, it's your money. It's not like I am forcing you to buy it, I'm just telling you what happened. Whether you believe it or not is your deal.

As for the injectors, they did fine on the dyno. A/F was right on spot after the tune. I do have a set of #30's on the shelf. They are about 10 years old, but still new in the wrapper. Actually, they are right next to a Vortech 73mm meter with a 30lb sampling tube that was also not needed.

It's really not THAT many mods. When I put in the new cams and port the heads and intake this spring, the 30's will need to go in at that point. It's not that high on the list right now, I'm really trying to get the 5.4 DOHC ready to run at this point.

 

I am going to try it. Just because I love to see the results of stuff like this. Just so we are clear, you gained OVER 180 miles on ONE tank of gas? That's using a 26 gallon tank. If I gain HALF of that I will be truly amazed.

 

works for me in my truck.. and in the work truck which is a diesel. and we drive to and from dallas.

 

those have alot of timing chain slap problems at around 70K + miles

 

I need to hear about this 14° base timing.
How did you set it and measure it?
I know how to measure it and make a change but want to hear about how you made the change.

Incidently, you do know that RXP is pretty close to you, in the same state!
The motorcycle shop that wrote the newsletter that RXP uses on their website has some questionable and miss information about fuels and there effective ability to generate power.
The flag is up!.

 

If anyone else has had any success with this stuff, please chime in. I don't feel like wasting my time and money if this is really some major BS...

 

I filled up here, in town, then again in New Mexico. I always pump in as much as it can hold. I rock the truck to get some air out, and try and try to get as much in as possible. Plus, I try to buy fuel when I get down to a quarter tank when I am on the road. So I filled up here, when I got gas again in NM, I had traveled 400.6 miles on the trip meter and took on 18.2 gallons. Do the math. It comes to 22MPG.

It needs to be said too that I was traveling between 80-90mph most of the way, so the truck was at around 2,500RPM most of the time. It would have probably been even better if I had drove at the speed limit. I also try to drop the gate on the highway, and I had it down both ways. The RXP may work even better at cleaning things out at those higher RPM's.

People are using RXP all over the country to pass emissions tests, and that's how I heard about it. Most any car with cats that still fails will pass after just one tank full of RXP. Now, to do that, it has to be cleaning something!