My Dad just purchased a 1997 F-250 PSD w/ Auto Trans. I've never driven a Diesel with the Throttle-by-wire system and noticed that it doesn't accelerate like my 93 F-250 Diesel. Is this normal? Is there any way to improve the throttle response as like on my 93? It feels like I push it 1/4 the way down before I get it to move. I'm also trying to get him to install the Diablo delta module but he's one of those old-timers (no offense) that likes to leave well things alone. I just might have to take that truck for the weekend and do this stuff for him (what toggle switch? ).

Thanks,
Ariel

 

I have heard of people replaceing their gas pedal with some kinda thing called a "power pedal" , that elimates the sluggish accleration. I am sure someone will post ya a link or something.

 

Stick your head down by the go-pedel. It will have a little "wing" that pushes the TPS (throttle possision sensor), if you bent that wing in alittle more (do small amounts at a time) but not enough that it keeps the sensor pushed in. Then when ya push on the pedel it wont have to travel so far untill it tells the computer to give it more ruel.

Another thing you can do is to shim the fuel regulator. It's kinda hard to explain it off the top of my head. I'll look for a post on a nother board that has some step by step instructions for ya.

 

The throttle response issue you're addressing is entirely controlled by the computer program Ford's engineering group felt was best. It would have been extremely easy to have made the first increment of throttle increase at the pedal electrical sensor correlate with a much higher incremental change in the injectors' pulse width. But that would have created a rather "jumpy" low level throttle response which in delicate situations would have been aggravating rather than a pleasure. Apparently it would please you to have a less gentle ramping up toward full power from an idle condition. Neither is outright "better", both gentle and aggressive slope ramp-up work. The stock gentle ramp-up is more versatile. The more aggressive slope would feel more jumpy and in many situations be more fun. Maybe some clever person will figure out how to give you a switch by which you can select G or J for "Gentle" or "Jumpy." Drive by wire makes choices like that comparatively easy to create. I'll bet that when your honey is standing behind your truck trying to attach the hitch to your tow ball, you'd have that switch in the factory "G" position. In that kind of situation, "Jumpy" might make you appear to be a Jerk. On balance, I think the factory response curve is a good compromise. As a matter of fact, I can't select an rpm between 500 and 800. One more increment between would be fine with me.

Interestingly, the same term, "throttle response" is also applied to how much excess horsepower is instantly available at any given vehicle speed/rpm combination. A "tall geared" PowerStroke fitted with an aftermarket 3.08 differential ratio with its transmission in overdrive has less instantly available excess horsepower beyond steady state cruising horsepower requirements than an otherwise identical vehicle with a 4.10 rear end at the same speed. Someone addicted to having lots of instantly available excess horsepower beyond cruising load requirements is likely to complain about what they perceive to be terrible throttle response from the clean running 6 speed that gets 24 mpg. The owner of the 3.08 rear geared truck might argue that he can simply down shift to approximate the speed/rpm relationship of the 4.10 geared truck. So long as we don't have the factory option of something like 2.75 rear gears with one of the excellent Spicer all-syncro 7-speed medium duty transmissions, we can't "have it all." If they offered that combination as an extra-cost choice, people would stop discussing ad nausium how you must choose either a great towing rear end ratio or a highway cruising ratio or some compromise between them. There is ABSOLUTELY NO REASON we can't have the best of both in one system. As the technical explanation on Randy's Gears explains, numerically lower ratio ring and pinion sets are stronger than high numerical ratios because they have more tooth contact area at any moment. Adding 10 pounds or less to drive shaft weight would more than take care of higher average torque loadings.

But that would not remove the urge to run in an rpm/speed relationship which leaves lots of instantly available excess horsepower. People addicted to lots of "throttle response" would just have to cruise the Interstates in one or two gears lower than is needed to easily sustain cruising speed. The rest of us could get better fuel economy when running empty yet have excellent ratios for towing heavy trailers through mountains. There's no doubt that jumpy throttle response boosts egos and "feels more powerful," but that is not an indication of true power no matter how much fun it is.

In case anyone thinks these Spicer all-syncro 7-speeds won't bolt up to a PowerStroke, touch base with your nearest International truck dealer and ask if he happens to have a 444 engine with 7-speed Spicer on his lot. Take one for a spin and see whats possible using only currently available already fully engineered systems. Maybe if a lot of us wrote to Ford and asked for this as an option with the new 6.0 diesel?
John

 

>The throttle response issue you're addressing is entirely
>controlled by the computer program Ford's engineering group
>felt was best. It would have been extremely easy to have
>made the first increment of throttle increase at the pedal
>electrical sensor correlate with a much higher incremental
>change in the injectors' pulse width. But that would have
>created a rather "jumpy" low level throttle response which
>in delicate situations would have been aggravating rather
>than a pleasure. Apparently it would please you to have a
>less gentle ramping up toward full power from an idle
>condition. Neither is outright "better", both gentle and
>aggressive slope ramp-up work. The stock gentle ramp-up is
>more versatile. The more aggressive slope would feel more
>jumpy and in many situations be more fun. Maybe some clever
>person will figure out how to give you a switch by which you
>can select G or J for "Gentle" or "Jumpy." Drive by wire
>makes choices like that comparatively easy to create. I'll
>bet that when your honey is standing behind your truck
>trying to attach the hitch to your tow ball, you'd have that
>switch in the factory "G" position. In that kind of
>situation, "Jumpy" might make you appear to be a Jerk. On
>balance, I think the factory response curve is a good
>compromise. As a matter of fact, I can't select an rpm
>between 500 and 800. One more increment between would be
>fine with me.

I never thought of that. WHY can't a 7 speed work in a Ford? I have never looked at one that close to see what size it is, BUT it seems that would be a super transmission to back up the Powerstroke.
>
>Interestingly, the same term, "throttle response" is also
>applied to how much excess horsepower is instantly available
>at any given vehicle speed/rpm combination. A "tall geared"
>PowerStroke fitted with an aftermarket 3.08 differential
>ratio with its transmission in overdrive has less instantly
>available excess horsepower beyond steady state cruising
>horsepower requirements than an otherwise identical vehicle
>with a 4.10 rear end at the same speed. Someone addicted to
>having lots of instantly available excess horsepower beyond
>cruising load requirements is likely to complain about what
>they perceive to be terrible throttle response from the
>clean running 6 speed that gets 24 mpg. The owner of the
>3.08 rear geared truck might argue that he can simply down
>shift to approximate the speed/rpm relationship of the 4.10
>geared truck. So long as we don't have the factory option of
>something like 2.75 rear gears with one of the excellent
>Spicer all-syncro 7-speed medium duty transmissions, we
>can't "have it all." If they offered that combination as an
>extra-cost choice, people would stop discussing ad nausium
>how you must choose either a great towing rear end ratio or
>a highway cruising ratio or some compromise between them.
>There is ABSOLUTELY NO REASON we can't have the best of both
>in one system. As the technical explanation on Randy's Gears
>explains, numerically lower ratio ring and pinion sets are
>stronger than high numerical ratios because they have more
>tooth contact area at any moment. Adding 10 pounds or less
>to drive shaft weight would more than take care of higher
>average torque loadings.
>
>But that would not remove the urge to run in an rpm/speed
>relationship which leaves lots of instantly available excess
>horsepower. People addicted to lots of "throttle response"
>would just have to cruise the Interstates in one or two
>gears lower than is needed to easily sustain cruising speed.
>The rest of us could get better fuel economy when running
>empty yet have excellent ratios for towing heavy trailers
>through mountains. There's no doubt that jumpy throttle
>response boosts egos and "feels more powerful," but that is
>not an indication of true power no matter how much fun it
>is.
>
>In case anyone thinks these Spicer all-syncro 7-speeds won't
>bolt up to a PowerStroke, touch base with your nearest
>International truck dealer and ask if he happens to have a
>444 engine with 7-speed Spicer on his lot. Take one for a
>spin and see whats possible using only currently available
>already fully engineered systems. Maybe if a lot of us wrote
>to Ford and asked for this as an option with the new 6.0
>diesel?
>John

 

I've thought of it before. Or maybe I should say 'dreamed' of it. With 95+% automatics being produced, they don't seem to much care what the manual tranny people want. To me the automatic contributes to the 'dumbing down' of society. People don't drop down a gear when going down a hill, approaching a stoplight, or just when they want to slow down. They mash the brakes at the last second. Then when the light turns green, they mash the gas and race up to the next light, only to wear their brakes again. Chevy had to have Allison engineer-in a grade braking feature. Apparently it is too difficult for the idiot (driver) to drop down down a gear when going down a grade. I can't stand the way the automatics run away with you. Whenever I drive someone else's car or truck, I always find it disturbing how it tries like hell to get into top gear, and will never downshift unless more power is required. The manual is great in low traction situations (snow, slick mud), too. You can start in 2nd gear if you want to. The automatic always starts in first. I test drove a GMC with my brother (just kicking tires). He said that I shift my 6 speed smoother than the GMC runs through the gears. I have rambled for too long. I think I have made my point: Manual transmissions are superior-I know they would never win a race against an automatic.

 

I agree with you on automatics helping to dumb down society. I see all kinds of people who can hardly operate an auto let alone a manual. I won't have an automatic in my stable. I told my wife she has to have stick in the Jeep Cherokee. She wasn't a hard sell though. She grew up on manuals and motorcycles. My 6 yr old daughter will learn to drive a manual as well, even though all the driver's ed cars are autos.

 

The automatics in the 6.0 Power Stroke gives you everything you want, including automatically dropping down going down hill....