So I live in the foothills mountains west of Denver at 7200ft altitude. When we camp or ski we go as high as 10000 feet or more. We all know altitude takes away power with a lower air pressure to feed the engine. In this altitude range it should be down nearly 30% on power.
So, when driving the highway, loaded with family, I often need to keep the thing floored going uphill just to maintain 50mph. It's even worse if I'm towing my 1800 pound pop up camper too.
So how bad is this?
Anyone else at altitude have experience? I think I really need more power!

 

That will definitely cause problems long term. How open are you to pulling the heads? Throw a torque cam in it, bleed down lifters, and a port and polish?

 

on a side note, this doesn't even kill the gas milage! It does a good job of leaning out the fuel at altitude, so it still gets like 13-14mpg

 

I know it SEEMS bad, believe me, but what is the actual problem?
So as I understand it, technically an engine is most efficient at wide open throttle.
So what specifically is the problem?
I'm watching the temps, never over 210.
Is there a known poor oiling or cooling problem with these at high RPM?
I'm WELL under the max load and max trailer of 7700pounds, (in what world can this pull a trailer that heavy?!) so in theory it should be ok, no?

 

but perhaps it's time to find a donor 03-04 engine and start building it up. I could use that extra torque badly

 

It puts extra wear on all the internal components, especially all the bearings. 210 is too hot too. I mean, it's not a super damaging temp, but most guys (myself included) try to stay under 200 because of the finicky head gaskets.

The engine is actually not most efficient at WOT. Maximum efficiency varies between engines, transmissions, gearing, tire size, and weight, but it is typically at a lower RPM because that is where the engine is putting forth the least effort to maintain it's speed.

I've got a set of 4.6 crank/rods/harmonic balancer that I'd sell and ship to you for around $300 if you ere interested in converting to a 4.6. You'd be better to stock with the 4.0 block because they were machined better and just upgrade the crank/rods.

 

The parts in the engine are obviously spinning twice as fast as the same car revving at 2.5k. This has to half the life of mating surfaces, bearings, piston rings etc. of course, only for that 3 minutes.



I think it's interesting about the fuel economy. Only so many oxygen atoms are entering the engine, so only a corresponding number of fuel atoms are being burned. Fascinating really. (To me).

 

It's really even less than half the life for that three minutes. During that period it's not only spinning twice as fast, but also the parts have twice as much momentum in their direction of travel putting twice as much friction on the bearings and other mating surfaces and twice as much pressure on the crank/rods, meaning it would quadruple the wear, plus the extra heat that increases it that much more plus what evened other factors I'm not taking into account because I decided engineering school wasn't for me.

 

Lets discuss the 4.6 conversation kit. I was going to buy a Donor car, but you've done the removal. Lets pm.

So as I've heard the 4.0 heads and block sleeves are better. If I'm doing the conversion, are there upgraded pistons or rods I'd want? Could i keep the heads on during the change?

Also: does anyone supercharge?

 

I would keep it at 3000.
You don't need to go so fast.

I would never tow with it either.

This is not a Ford Super Duty Diesel or a Dodge Ram
and should not be treated like one.