I'm looking at a 2007 Supercrew F150, and want to know if there are performance or maintenance issues between the regular and flex fuel V8's. It one better than the other?

 

I have heard from others that when the use Flex Fuel, thier mielage goes way down..

 

There Is Know Difference. They Run The Same And Maintence Is The Same. You Just Have The Option To Run E85

 

[QUOTE=benningstspeed1.0]There Is Know Difference. They Run The Same And Maintence Is The Same. You Just Have The Option To Run E85[/QUOTE


If so, why can't you get the heavy payload package and the FFV 5.4L on the new 2007 or 2008 trucks?

 

more than likely it is because when running on E85 it doesn't make as much power that on reg. both are rated at 300hp, and my 5.4 ffv pulled 8500lbs just fine.

 

Just wondering, if you have a standard EFI can you in an emergency run the E85 until the next fill up? didn't mean to interrupt just curious. Thanks.

 

No, I don't think so. There was a really good post a while back that explained the differences in the fuel systems on a E85 FFV and the regular engine. You might do a search and see if it comes up. From what I remember about the thread, there were considerable differences in the two. I just did a search "E85 FFV" and there was alot of info there. Hope this helps.

 

I have a 2007 F150 that runs the 5.4 flex fuel. As far as performance and maintance there is no real difference. you do lose about 1/3 of the milage when running E85 instead of regular gas.

 

differences between normal vs. ffv are minimal. perfomance adders will have the same effect on a normal and FFV motor

the FFV gets the same power and mileage as the normal with normal gas.

when using E85, the FFV makes the same power, but it uses more "gas". the E85 contains less energy than normal gas, so more "gas" is used.

if in emergency, don't. the E85 is very corrosive and will cause trucks fuel system to fail. the FFV is made of specific components to prevent fuel system failure while using E85

 

I know up here i couldn't even find a non ffv truck...everyone of them was that way. And it was going to take weeks longer to order it once i decided to order a truck instead of taking one off the lot.

 

Almost all gas companies mix E85 with there gas...so if your truck/car runs regular then o well you are going to be putting E85 in it anyway...Well thats how it is on the East Coast.

 

We put E85 in our '98 Expedition a while back coming back on the highway. It ran rough for a while, like a tank maybe two, but it was completely fine after that. Not rough enough to die but it was rough enough to make me think to myself that the E85 caused it. I am almost sure that you could run any car on E85 (for emergencies) from anything like about '97-'98 and up.

If you put in a tank of E85, I seriously doubt it would cause long term damage.

-rockstate

 

It wouldnt cause damage...like you said rough idle, but i dont like E85 IMO leaded gas was alot better than the crap we're feeding our engines.

 

I Have Seen Car Come Into The Dealer Ship That Had To Have Fuel Pumps And Other Things Replace From Running On E-85 That Were Not E-85 Compatible. If You Are Not E-85 Compatible Your Fuel System Isn't Calibrated Right. It Take Higher Volume Fuel Pump, Hight Flow Injector, And Different Computer Calibration

 

Looking at the specs of the Dudge FFV 4.7, It makes the same HP but higher in the RPM range, same with TQ, compared to the regular 4.7. Anybody have the specs and ratings for the 5.4L's?