is a 5.4 l as powefull as a 5.8l?j ust wondering thanks

 

Stock the 5.4L is more powerful by far. The last year 351's were around 230 or less the first year 5.4L's were 235 and upped to 260 then 300.

 

FYI
I went from a 1986 F150 with a 5.0 and manual tranny w/ 3.73 gears, to a 1996 F150 with a 5.8 and auto w/ 3.55 gears to a 2006 with a 5.4 and auto w/ 4.10 gears.

Best drag racer... the 1986.
Best for pulling a trailer... the 2006.
Best fuel economy measured... the 1986.
Worse drag racer... the 1996.
Worse for pulling a trailer... the 1986.
Worse fuel economy measured... the 2006.

Cheers... Bruce

 

5.4 more powerful by far. hands down in my opinion.

 

where all the trucks similar weight and cab configuration, and drive train like 4x4.

cant compair apples to oranges here

 

In stock form, the 5.4 will own the 5.8.

However, the 5.8 is cheaper and easier to build.

FWIW, the 5.8 usually makes more bottom end torque, due to the larger displacement and pushrod style valvetrain.

The 5.4 is just the opposite... OHC design favors high RPMs.

However, with the variable cam timing throwing more torque down low, the 3v 5.4 can do anything better than a 5.8.

I've owned 5.8, and both 2v and 3v 5.4s.

 

Where in the world does that urban legend come from???


A motor could not care less where its cams are in relation to powerband.

 

Comes from me driving, working, and owning both engines.

Also basic general knowledge.

Prove me wrong.

Until the 3v came out, peak torque in the 5.8 was at a lower RPM than it was for a 5.4.

Same goes for 5.0 vs 4.6, 460 vs. V10, on and on an on...

"A motor could not care less where its cams are in relation to powerband"


WTF are you talking about? The cam is the single biggest factor in setting the powerband!

 

How the cam is ground decides the power characteristics, has nothing to do with where it is on the block.

 

The cam is important (among MANY other factors that I'm sure I'll school you on later)............not where the cam is placed.


It's so funny when a lot of people on here tout the 5.4 as a "truck" engine that makes 80% of its peak torque at 2,000 RPM when compared to the push rod motors from Dodge and GM.

As far as your "lower" rpm comment....again, even if it was true, it has NOTHING to do where the cams are.

 

..................

 

OK now I see where you guys are going with this.

I'm not an engineer... or even an aspiring engineer... so I'm not going to try to explain the pros and cons of pushrod vs. OHC.

That being said, why is it that the pattern I've described fits the design... OHC motors like RPMs and pushrod motors make more grunt at the bottom end?

Whether or not "cam placement" has anything to do with it is irrelevant... the fact is, that's how these motors perform, and that's what I was pointing out to the OP.

Remember also, I mentioned engines in stock form.

 

I thought the 5.4 2v made more low down tq than the windsors anyway?

But you said yourself the 3v does so.

Thats the advantage to ohcs.. they can spin faster easier and more reliably, and with variable cam timing or double overhead cams you can have the best of both (low end tq and high end hp)

I want to see an engine with no cams, maybe some day.

 

Look, you seem to be a nice enough guy; so I'll give you a quick explanation.


OHC, in theory should allow SAFER high RPMS.....this is especially true on REAL DOHC motors whose cam lobes ride directly on the valves (usually a shim or bucket used to set lash)

Two things to remember though......Ford still uses rockers on there OHC motors AND a hydraulic "lifter" to set lash (except for the 3.5L V6) and all the new pushrod motors not only use roller lifter but also roller rockers.

Just take a gander at GM's LS motors and compare revving ability.

On to powerband, Bore and stroke, rod ratio, rod length, air flow into the heads, AND cam specs all contribute to where a motor will make power.

In other words, given all the same specs, there would virtually 0 difference in a push rod vs OHC motor regarding powerband.


And I repectfully disagree with you concerning the V10 vs 460 and the 5.0 vs the later 4.6's .....I, too, owned all the various versions and think the Mod motors make just as much low end and a tad more peak power.

 

I don't know the numbers off of the top of my head, but I don't think so.

My seat-of-the-pants evaluation told me that my '95 F-150 5.8 had better bottom-end torque than my '99 Expy 5.4 did. Gearing was pretty close in both.

Again, for what it's really worth to the OP. He hasn't chimed in or provided more precise clarification on his question, so I don't know if it really matters or if it was a serious question or not.