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[gmtech16450yz]

Good morning kids and welcome to my class!!! SO glad you could join me!

Lol. I think at 57 I'M the kid here?!

Today's lesson will be all about which fuel the Ford V10 likes better. My class has NO grades, NO tests, NO judgments and of course, NO stupid questions. I do give extra credit for participation though. And if you want to be the teacher's pet, bring me a cookie instead of an apple. Fruits and vegetables are dumb, burgers and fries are my friends. haha.

Ok so here's the first BIG lesson... The late model Ford V10 DOES NOT have a knock sensor! This is big. 99% of cars and trucks on the road have at least 1 knock sensor. GM has been using them on almost everything since the early '80's. This is big because it drastically changes how the factory "builds" the engine calibrations. Without a knock control system, they have to set the ignition timing and fueling so that on the cr@piest regular gas, in the worst situation for pinging, the engine won't knock. That means in the middle of summer, in the middle of Death Valley, the ignition timing has to be low enough that it doesn't knock, or at least not too much to cause damage.

(Fun fact #1... engines not only can handle certain amounts of engine knock just fine, they actually benefit from it!)

So if the timing is set to not ping in Death Valley, (below sea level and hotter than _____.) how do you think it's going to run going over that 13,000 foot pass in the middle of winter? Not too good! That's the major downside of not having any knock control. THAT'S what we have in the V10. The difference in optimum timing in those two situations can be as much as 20 degrees! The factory has to tune for the worst case, so without being able to control ignition timing in relation to knock means your timing can be 20 degrees away from optimum. That's a TON of power and efficiency. (That "20 degree" number isn't something that's set in stone, it's obviously a big ballpark number. The ignition timing in my Vegas engine calibrations is as much as 26 degrees away from factory in some areas.)

So what does that mean for you at the gas pump? Running premium gas IN THIS APPLICATION can actually result in LESS power and LESS MPG's. (Sorry about the YELLING, I tend to put really important things in all caps so that they don't get missed. And this is huge because it goes against so much "internet" knowledge. How many people think "race fuel" makes their engine stronger, when in fact it actually makes less power if it doesn't need it.) So the "in this application" part is huge because don't take what I'm saying here and try to apply it to ANY other vehicle. Again, 99% of the cars and trucks on the road have a closed loop knock sensing system, so they will, depending on application and engine, benefit from using premium gas.

So here's my advice for this application, running on the factory engine calibrations... Run regular gas unless you're towing a heavy load, running high speeds or in high temp/low altitude situations. Premium in those situations will simply give you a little extra safety because even on the SUPER conservative stock engine calibrations, the V10 can knock in those conditions.

(Fun fact #2... Pulling steep grades needs better fuel right? Not if those grades are at higher altitudes. Engines are far less likely to knock at higher altitudes because the air is thinner and it makes the cylinder pressures much lower. Even pulling grades at 2k or 3k feet your engine will be less likely to knock.)

There's obviously a ton more on this subject, but hopefully that will help clear up some common internet misconceptions about "Which fuel should I use?" And again, this only pertains to the late model Ford V10 because it doesn't have any knock control.

(Fun fact #3... After reading that, does it make you realize how much can be gained by an aftermarket tune in these engines? A TON! The fun fact is that Ford delays "Power Enrichment" for 60 seconds in the factory calibrations!!! This is enormous! So pulling that grade means your engine is running dangerously lean for a full minute before getting the proper fueling it needs for that amount of load. Let off the gas for a second and the 60 second timing starts back at 0. Yikes!)

Questions? Feel free to ask away! There's obviously a lot more to all of this and I'm happy to help clear up questions/thoughts/concerns if I can.