Guys I just need to voice my $.02 about our 5.4 vs 6.8L debate. Firstly, we can fight day in and day out about what is better, the V8 or the V10. That opinion will change from individual to individual... whatever to each his own.

Anyhow for your comparisons of 5.4L engines, do not compare F150 5.4's to F250 and 350 5.4's. The F150 5.4 is tuned differently, geared differently, and a different truck. F150's are EPA rated, therin must achieve a certain avg. mpg. Our superduties are not rated for this, and have lower gearing and different fuel trims. I personally believe my 5.4 ext cab longbed 4x4 feels a million times faster than the quivalent F150 with a 2 valve 5.4. Never driven a 3 valve, so no room to speak there. Both trucks did have same rear axle ratio.

Also, when doing these comparisons, please also try and compare similar years of engines/ trucks. This is an exageration but hopefully yall can see the purpose, but comparing a 99 5.4 to a 09 5.4 is like comparing a 1969 Chevrolet 350 to a 1996 Chevrolet LT1. To completely different animals, granted there is not that dramatic of a change in the 5.4 and 6.8's, but ya should get my drift.

And my final thought about this engine debate, once you compare apples to apples, if you ever have the opportunity to get the V-10 do it. Don't be afraid of a 5.4 because it is a pretty stout motor for what it is and can do~ but if the opportunity presents itself, just spend the few extra dollars and get it. If you have the V10 you can go pick on chevrolet and dodge diesels, instead of bickering about what engine is 'better'

 

+1... Well said.

 

i agree with you 5.4 it seems like all we do on here sometimes is get in discussions and arguments off the basis of how my dogs bigger than yours and stuff like this...we all have sd's, so why do we go against each other so often?

 

What I want to know is why the V10 has a lower compression ratio than the 5.4? My thoughts are the V10 would really kick the crap out of the 5.4 if it has the same compression ratio, then it would have a proportional power increase per extra cylinder than the current power differences?

Perhaps this lower ration accounts for the similar fuel economy despite the larger displacement? Or ford is making provisions for a supercharger

 

LOL like the comment about gonig out and picking on chevy/Dodge diesels..

when i had my 2WD V10 F250, i would always make a point to out run both brands trucks any chance i got..

esp. the guys with the modded up Diesels.. if i saw a fancy set of rims and a BIG exhaust tip, it was game on.. i never lost.. 8-)

i chased this one guy up a steep hill in a tricked out newer 24V Cummins 2500...was on his tailgate most of teh way till he pulled over and i gave him the army salute as i floored it and passed him...

V10 all the way...

 

I agree, the Super Duty is a good truck, regardless of the engine in it. Each engine has it's place, and for the most part, they all do the same thing (even the diesel ). So, be happy with the truck you got. If it were up to me, and the wife never had any say in the matter, I would have gotten a 5.4L plain jane truck. Unfortunately or fortunately there were options she wanted that meant I had to look for a different truck, and ultimately I found out about the small price difference for the V10 and looked for that as well. I found the perfect truck for the wife and I, with the V10, but I'd still be happy with a plain jane, vinyl interior with the 5.4L, because it'll still do d*mned near anything you can throw at it.

 

So does anyone know about compression ratio?

 

Yes...and?

 

Maybe something to do with the odd harmonics/balance of a V10 vs a V8?? Dunno...

 

is why the V10 has a lower compression ratio than the 5.4?

 

The 2-valve engines have the same compression.

The 3-valve 5.4L has VVT (really VCT) and a higher compression ratio than the 3-valve V10. The 3-valve V10 does NOT have VVT so it can't deal with the higher compression.

 

Which is? Sorry, don't know the acronyms.

Later...
Brewster...

 

Variable Valve Timing. Or more correctly on the Ford, Variable Cam Timing.

The cam timing changes as the PCM tells it to, to maximize torque at different RPMs.

 

What is the 2 valve compression ratio? DO you know if the ford modular is an interference motor or not? Wondering if ya could deck the heads on a 6.8L for a little more go power

 

Cool, I didn't know that.
Thanks!

Later...
Brewster...