Performance of the 4.6 in my super crew
#1
10-14-2004, 07:50 PM
Performance of the 4.6 in my super crew
Bought an 02 screw in July with the 4.6 , 4r70w and 3:55 gears.
Thought I might have made a mistake from the poor power it displayed.
As the time went on, the performance got markedly better until today is is satisfactory considering the size of the engine and the weight of the truck.
I concluded that the dealer must have had the battery disconnected and this rebooted the computer making relearning take place over time as the truck was used.
Other observations and reading on this site has produced a number of other assumption about the truck in general.
For most normal driving, the engine hardly ever revs much above 2500 rpm unless it is forced. This causes the engine to run considersably below its good torque band and makes the truck feel a bit gutless until you push the engine above 2500 were it starts to come alive.
With 281 cu/inches and 5365 weight, the engine peak torque is speced at 3500 rpm, with peak hp at 4750 rpm.
Is it any wonder that these trucks feel low on power being driven well under there peak torque 99% of the time.
Cruising in OD at 70 mph and 2000 rpm is not going to get you passing with any vigor unless the trans comes out of OD and down shifts another gear yet , then your on your way. Don't be afraid to run the engine up a bit when needed.
...............
Brake's short life on the front:
First be awhere that as soon as the brakes are touched the trans comes out of lockup. This takes away engine brakeing effects unlike the old AOD.
Notice the truck tends to freewheel and keep right on going making the use of brakes much more than the older trucks without the electric lockup transmission. Think the brakes should last as long as the old trucks under this kind of operation?
.....................
Summing up: with a small displacement engine, the overall torque is not is their until the engine is rpm'ed up to make some air pass through the engine in leu of larger displacement.
In cruise, the throttle is instinktively opened farther than there is power on demand for, making the fuel milage suffer as a consequence.
...........
The trans convertor is loose and electric lockup, while giving some nice operation, also contribute to lower performance in some ways and helps cause higher brake wear.
The trans lockup is programmed to release when the brakes are touched and re-engages again if the brake pedal is released.
With a tach and speedometer option, watching the actions of the tach gives away the operation of the transmission and what shifting goes on under different conditions.
Last comment is about the perpensity to spend large amounts of money on air intake aftermarket replacements.
With the engine operation mostly in the sub-torque range during normal nonperformance driving, there would be little or no performance gain for cost.
Exhaust has enough unrestricrted flow capacity also in this range to make it a questionable return for cost.
Like everthting else, a clean truck makes the owner feel better than a dirty one so the additions and changes must go on to get the looks, the sounds and the satisfactions.
Thought I might have made a mistake from the poor power it displayed.
As the time went on, the performance got markedly better until today is is satisfactory considering the size of the engine and the weight of the truck.
I concluded that the dealer must have had the battery disconnected and this rebooted the computer making relearning take place over time as the truck was used.
Other observations and reading on this site has produced a number of other assumption about the truck in general.
For most normal driving, the engine hardly ever revs much above 2500 rpm unless it is forced. This causes the engine to run considersably below its good torque band and makes the truck feel a bit gutless until you push the engine above 2500 were it starts to come alive.
With 281 cu/inches and 5365 weight, the engine peak torque is speced at 3500 rpm, with peak hp at 4750 rpm.
Is it any wonder that these trucks feel low on power being driven well under there peak torque 99% of the time.
Cruising in OD at 70 mph and 2000 rpm is not going to get you passing with any vigor unless the trans comes out of OD and down shifts another gear yet , then your on your way. Don't be afraid to run the engine up a bit when needed.
...............
Brake's short life on the front:
First be awhere that as soon as the brakes are touched the trans comes out of lockup. This takes away engine brakeing effects unlike the old AOD.
Notice the truck tends to freewheel and keep right on going making the use of brakes much more than the older trucks without the electric lockup transmission. Think the brakes should last as long as the old trucks under this kind of operation?
.....................
Summing up: with a small displacement engine, the overall torque is not is their until the engine is rpm'ed up to make some air pass through the engine in leu of larger displacement.
In cruise, the throttle is instinktively opened farther than there is power on demand for, making the fuel milage suffer as a consequence.
...........
The trans convertor is loose and electric lockup, while giving some nice operation, also contribute to lower performance in some ways and helps cause higher brake wear.
The trans lockup is programmed to release when the brakes are touched and re-engages again if the brake pedal is released.
With a tach and speedometer option, watching the actions of the tach gives away the operation of the transmission and what shifting goes on under different conditions.
Last comment is about the perpensity to spend large amounts of money on air intake aftermarket replacements.
With the engine operation mostly in the sub-torque range during normal nonperformance driving, there would be little or no performance gain for cost.
Exhaust has enough unrestricrted flow capacity also in this range to make it a questionable return for cost.
Like everthting else, a clean truck makes the owner feel better than a dirty one so the additions and changes must go on to get the looks, the sounds and the satisfactions.