TOPIC: 6.8L v10 drivers - check this out

I've been thinking about what this guy has done with regards to what I'm thinking about over in another thread Taking a groovy car to the next level - Groovy Forums
Read it from the beginning to see where my head is at, and to support the comments I've made on this video:



To the best of my knowledge, this truck doesn't have the groove on it. (I suspect if it DID, things might be slightly different)

The first concern that is mentioned is that he sees an increase in power, but no accompanying increase in mileage. My experience tells me it's because he needs to address the signal(s) his computer sees at the oxygen sensor(s) with an EFIE modifier circuit per upstream sensor. more power means more fuel is getting burned more efficiently....but if there is more oxygen in the exhaust than the computer expects, it'll open the injectors for longer and increase fuel delivery to balance the equation (Ford) engineers go by. tweak the sensors, fix that problem.

(well, it could also be that he likes to put his foot into it and keep it there. power can be fun )

The next issue is that the preheater eventually warms up the fuel in the tank to a point he is concerned that it might cause problems, possibly like vapour lock. I have 3-4 possible fixes here:
1- First, modulate how much hot coolant goes into the heat exchanger. If it is a matter of too much heat from the coolant, maybe taking the exhaust manifold heat wrap off the exchanger would help with this (ok, that's 2 ideas - lol)
2- cool the fuel in the return line to some extent somehow.
3- trigger the EVAP system to purge more often - or even continuously - so that a vacuum is applied to the fuel tank that draws extra vapour into the manifold directly (using the existing system built for that purpose) - and that bleeds off extra heat from the fuel. This is a simple electronic "hack" similar to the EFIE, and I'd wager that some of this - modifying 2 aspects of what the computer monitors and reacts to - is the way to get more, better, consistent fuel economy gains out of this truck
a 4th option is that all of these need to be applied.
a 5th option is that the fuel supply to the exchanger be reduced, if you don't heat as much up, what goes back to the tank won't be so hot and need to be cooled. (if what's in the fuel rails is already or mostly vapour, the return line may end up being moot...it would be interesting to see if theres a pressure regulator on the rail and if the computer might throw a code)...I suppose you could also restrict the output from the exchanger to the rail...but that backpressure on the pump may cause it to cavitate. maybe restrict input and output of fuel as well as option #1 above - less heat AND less fuel coming in contact...so, that's a 6th option. or is it a 7th?
another possibility is that he could increase the air volume/mass/pressure at the TB with a "ram air" setup like I put on mine (and mentioned in that thread at the top of this post). more cold air might balance out the surface area of the warmed fuel to get the computer to tweak the injectors to close a bit more - this is kind-of a non electronic way to tweak the MAF sensor signal if you turn our perspective around a bit. (he should also dump his K&N filter for the stock Ford filter...after cleaning his MAF, of course)

he posted that the engine doesn't have an EGR system - did he delete it, or did it not come with one from the factory? the venting of hot fuel vapour from the tank with my EVAP system idea may in effect replace this deletion/oversight.

Tracy, your thought on my ramblings? or anyone else who's got an F-series with one of these beast engines, for that matter - jump in and share your perspectives, please! I always want to learn what other people think!

I don't know much about these beast engines and haven't had time to watch the video. So this will be a quick 2 cents thrown in. If he's looking for a return fuel cooler, most modern diesels run a return fuel cooler. I would venture to say one could be rigged or spliced into the return line to cool the fuel. I have not priced one so don't know how costly of an idea it would be.

Warming fuel up on the way into the engine and then back down again on the way out is probably the safest way to proceed.
That said, I'm sticking with some of my other suggestions to enhance all of the aspects of this potential mod to this engine.
maybe one of the people checking this thread out who have a vehicle with this engine can try some of the things I listed and report back with their results.
I know Tracy has grooved a bunch of TBs for owners, we just need them to take a moment and drop us a line with their news.

Hello Gadget people. I did show this video to Ron, a few years back. He mentioned that preheating the fuel causes some issues. Here is my take.

Think about what mods need to be done to get the groove to work on some obd2 vehicles. Since the engine is now running 100 degrees cooler we need to insulate the exhaust with a wrap. This fellow is heating the fuel causing the engine to use less of it's heat energy in the intake to vaporize the fuel. If he wrapped his exhaust system he would possibly gain back some of that mileage and still keep the power.

I've sent this fellow links to Ron and Tracy's discussions on here about wrapping the exhaust system.

The rear o2 sensor, in some obd2's vehicles, measures the temperature of the exhaust. Any major improvement in combustion efficiency, (such as the Groove, fuel preheating, water injection as examples) will cause cooler exhaust. So, he needs to wrap.

Also, if he does keep the fuel preheater he should really follow Mike Holler's advice on that topic. It involves adding a solenoid, just before the intake. It closes when the ignition is off. He also suggests using an adjustable one way check valve to prevent the check engine light coming on.

All of the above sounds so darn complicated. Why doesn't this guy just get grooved? Ron was a master at keeping things as efficient yet as simple as possible. No efie needed.

Aaron wrote: The rear o2 sensor, in some obd2's vehicles, measures the temperature of the exhaust.

There has been some discussion on the function of o2 sensors in fuel delivery in general, with speculation they may simply be thermocouples that have been renamed to give them increased significance.
Tracy and I were discussing how a mod one of his customers suggested might be perceived by computers, but we never arrived at any significant conclusions. I suspect that heated sensors have the current on the heater circuit read by the computer in addition to the temp difference between exhaust and air outside the exhaust system (the thermocouple) to arrive at some measure of stoichiometry (14.7ish:1 air-fuel ratio...and remember it's MASS of air to mass of fuel - 14.7grams of air to one gram of fuel vapour)...but this would imply it's a speed-density circuit on the exhaust to balance the speed-density induction/intake monitoring...which may actually be the case - we simply don't know for certain and have always considered them related but seperate, the MAF/MAP and up/downstream o2 sensors, but engine monitoring also includes knock sensors and cam/crank ignition timing sensors and coolant temp sensor. Nobody at the home/enthusiast level has reverse engineered how an OBD ECM/ECU actually controls emissions/power by adjusting injectors/spark by manipulating one factor at a time.

I think significant efficiencies can be achieved by using exhaust heat to warm engine coolant from a cold start...that, in my estimation, will bring the engine to closed loop fuel delivery sooner/faster. allowing the air/fuel electronics on intake and exhaust work better/sooner, and cars will use less fuel and therefore pollute less, period.
Someone might want to invent a system that replaces fuel injectors with a simple/reliable temp-controlled fuel cell system that keeps gasoline just below its vapourization point so that we can allow an engine to inhale warm vapours to burn - the most efficient way to deliver petrofuels to an internal combustion engine...

wouldn't it be super cool to have the time to experiment and truly figure these things out so we could make great powerful fun efficient cars and trucks?