460 Ford Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
Ok guys heres a question...

I got a 97 F250 HD,club cab, 2wd, E4OD, 460, with a 4.10 rear. All stock, 84k miles.

My buddy has a 02 2500 HD Chevy 4x4, club cab, short box, with a 6.0L and a 4L80E trans (i believe). Also with 4.10s, with 145k miles.

This last weekend we were screwin off and he had a 16ft car trailer with 2 mowers on it, pry around 3-3500lbs total.

I couldnt pass him from 55,which i expected, but was shocked when i couldnt best him from a 15mph roll.

I was empty.

My truck doesnt seem to have any issues, so what gives?

I understand he has me smoked in HP (245-340) But i got him in torque (410-365), and at a much lower rpm (2200-3650).

So, is the 6.0L that amazing? Or am i right in thinking with a heavy load behind both (say my 7000lb travel trailer) and a steep hill the outcome would be different?
 

·
Registered
Joined
·
285 Posts
DZG,it may have to do withe the shift program of your E4od,every gas truck I have driven with that trans with a stock shift program left a lot to be desired as far as early upshift points and 2-3 shift which gets you almost immediately into locked converter mode at relatively low RPM,whereas the GM trucks I've driven with LS style engines and 4L80E seem to have a much more aggressive shift program,more willing to stretch the rpm's before shifting and much more willing to downshift as necessary.B&M used to and may still market a shift improvement programmer for the E4OD and I have one but have never installed it because it entails splicing into the harness so I can't attest to if it actually improves anything.It almost seems that Ford was intensely focused on getting max. fuel mileage to the point it was at the expense of performance.
 

·
Registered
Joined
·
577 Posts
John is absolutely right. It seems Ford programmed the E4OD for the 7.3 Powerstroke and used the same setup on the 460. The 4L80E with the 6.0 will constantly hunt and find the optimum gear for best case rpm for max performance to suit road conditions and load. Makes the smaller GM motor look good but the constant shifting under load is irritating and along with it comes frequent trans work and bad fuel economy. Not saying the 460 is ever going to have good fuel economy but like John says,that must be what they were shooting for. Boom,boom,boom,lockup...and you're not to the end of the block.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #4
I do think its funny that we both get 13mpg.

So, if we were to run again would i gain an edge by shifting manually? Or even locking out O/D?

He got an enourmous head afterwards, i just told him youd outrun my peterbilt to, doesnt mean youd outpull it :)
 

·
Registered
Joined
·
285 Posts
Manual shifting will help just don't go overboard your 460's powerband is a lot lower than a 6.0,you' d be surprised how often people rev an engine too far past its powerband and are surprised when it is slower.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #6
Yeah i found that outnthe time i was racing my 96 F150 (300 I6) i used to have, i was a dumb kid and figured since it was shifting at 3500 it would be faster if i manually shifted it at 5.

It wasnt :)

Ive been wanting to swap in a factory tach gauge cluster mainly to monitor RPM going down the freeway with my camper.

What would be a good RPM to shift at? And what RPM is to high for sustained freeway towing?

Also, what rpm do they shift stock?
 

·
Registered
Joined
·
285 Posts
DZG,without having a dyno sheet showing what you hp and torque curves are its hard to determine optimal shift points it depends on how fast hp drops after peak.That being said if you have the rpm at peak hp a good conservative rule of thumb would be to stretch it out a couple hundred rpm past that(you may have shift at peak hp rpms in order for the shift to be complete by then though depends on how quickly you trans shifts)you probably would need access to track timers or a G-meter to be able to experiment and find the optimal.As far as sustained towing, for the sake of my friends and family traveling the highways not being passed by a pickup towing a big trailer at an insane rate of speed I would say whatever rpms gives you 65-70 mph.Depending on how heavy your trailer is if your towing on flat ground with little headwind you may be able to get away with towing in OD but I wouldn't recommend it and neither does the manufacturer.Also if you are towing regularly or long distances make sure your truck has all the towing package coolers and they are working well.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #8
I usually keep it slower then that, i usually run max 65mph on the freeway, and do have all the coolers.

I wont tow in O/D. Unless its a light load.

I just was wondering since i dont have a tach, running 65 in 3rd for a distance isnt asking to much?
 

·
Registered
Joined
·
285 Posts
I usually keep it slower then that, i usually run max 65mph on the freeway, and do have all the coolers.

I wont tow in O/D. Unless its a light load.

I just was wondering since i dont have a tach, running 65 in 3rd for a distance isnt asking to much?
Assuming 32-33 tall tires 65 mph in direct(3rd gear in E4OD) it should keep you comfortably under 3000 rpm,my sons powerstroke 5 speed with 4.10's&35's runs about 2600 rpm at 65-70 in 4th gear(direct).Any sound 460 with properly operating cooling system and oil coolers should live at 3000 rpm provided it is in a good state of tune and has proper octane gas.
 

·
Registered
Joined
·
6 Posts
(edited)
Ok guys heres a question...
This last weekend we were screwin off and ... I couldnt pass him from 55, which i expected, but was shocked when i couldnt best him from a 15mph roll.
  1. VEHICLE 1: 1997 F250 HD, club cab, 2wd, E4OD, 460, with a 4.10 rear. All stock, 84k miles.
    1. assumed that "club cab" refers to Ford's Extended Cab; and
    2. with a tank full of gasoline and an otherwise new-car-showroom empty cab and bed, and no accessories or doodads added to the described truck, it's at roughly 5400 pounds, plus the weight of the driver. small and easily-overlooked or forgotten stuff adds-up really quickly, but I won't impose a guess how much of that is being toted.
    3. SAE Net Horsepower: 245 @ 4000 rpm; 180.5 @ 2400 rpm
  2. VEHICLE 2: Description does not match any vehicle produced by Chevrolet or GM.
    1. assumed that "club cab" refers to Chevrolet's Extended Cab; and
    2. The 2002 Chevy 2500HD 4x4, with Extended Cab, short box, and a 6.0L (with a 4L80E trans, 4.10s, with 145k miles),
      1. with a tank full of gasoline and an otherwise new-car-showroom empty cab and bed, and no accessories or doodads added to the described truck, it's at roughly 5600 pounds, plus the weight of the driver. small and easily-overlooked or forgotten stuff adds-up really quickly, but I won't impose a guess how much of that is being toted. the near-identical weights of the "foundation" vehicles is an incredible coincidence; I wish you'd have them weighed in as nearly the same condition as they were when you conducted your "comparative acceleration" exercise.
    3. Trailer weights vary pretty hugely for approximately-identical styles and nominal dimensions; a normal "16ft car trailer" could easily be 1800-2000 pounds, and a flyweight version could be closer to 1600 pounds. A cheap zero-turn mower might weigh as little as 650 pounds; a quality zero-turn mower is 1150-1450. So, assuming nothing on the trailer but the 2 mowers, and mid-spec stats on everything, that's around 4000 pounds -- but it could easily be 4900-5000 pounds, and it could just as easily be 2900 pounds; 3000-3500 is within the range; i guess a Chevy guy might err towards the "hobby-grade" end of the spectrum.
    4. Combination vehicle weight:
      1. 6.0 gasoline V8, A4 transmission: 8900 pounds;
      2. 8.1 gasoline V8, A5 transmission: 9700 pounds.
    5. SAE Net Horsepower:
      1. 6.0 gasoline V8, 4-speed automatic
        1. 300 @ 4400 rpm; 274.2 @ 4000
      2. 8.1 gasoline V8, Allison 5-speed automatic
        1. 340 @ 4200 rpm; 277.2 @ 3200
  3. Weight-to-Power with only 1 occupant (the driver) in each vehicle @ 200 pounds:
    1. VEHICLE 1:
      1. 5600 lbs / 180.5 hp ~ 31.025 lbs / hp
      2. 5600 lbs / 245.0 hp ~ 22.857 lbs / hp
    2. VEHICLE 2:
      1. 6.0 V8
        1. 8900 lbs / 274.2 hp ~ 32.458 lbs / hp
        2. 8900 lbs / 300.0 hp ~ 29.667 lbs / hp
      2. 8.1 V8
        1. 9700 lbs / 277.2 hp ~ 34.993 lbs / hp
        2. 9700 lbs / 340.0 hp ~ 28.529 lbs / hp
  4. I understand he has me smoked in HP (245-340) But i got him in torque (410-365), and at a much lower rpm (2200-3650).
    1. Your numbers don't jibe.
  5. My truck doesnt seem to have any issues, so what gives?
    1. I refer you to the foregoing.
  6. I was empty.
    1. How certain of this are you? I ask because it seems much more credible that you were loaded.
  7. So, is the 6.0L that amazing?
    1. No: the 1997 Ford 7.5-liter V8 is just exceptionally crappy in its OE configuration.
  8. Or am i right in thinking with a heavy load behind both (say my 7000lb travel trailer) and a steep hill the outcome would be different?
    1. You're kidding, right?
 
1 - 10 of 10 Posts
Top