Forum Discussion
ShinerBock wrote:
I thought the only gas truck to come with a 4.30 with the new 10 speed was the Tremor due to it's 35" tires.
I don't know the specifics, just trying to show speed vs hp potential of the 10 spd.
If fuel economy wasn't a concern, I'd gear the gas so the speed in each gear matches a diesel's. If the diesel came with 3.73, then the gas would need 7.32. (5500 rpm vs 2800 rpm hp peak)- All modern diesels use a form of torque management that maintains constant crankshaft torque regardless of FEAD (front end accessory drive) loads. Gas engines generally don't do this, except for the "downrated" 320 HP V10, which performs quite a bit better than the previous version rated at 365 hp.
Groover wrote:
RoyJ wrote:
dodge guy wrote:
Yes, better gearing will tow better. Glad you now understand!
And with enough gearing (10 spds), two engines of the same hp, one with double the torque, will perform IDENTICAL except right off the line.
I hope you understand that now.
I agree with you in principle but in every dyno test I have seen the diesels produce much more of their rated horsepower than the gas engines in the same vehicle. So, a diesel will frequently outrun a gas engine of the same rating. I haven't found any explanation for this and it is just a personal observation. It may have something to do with diesels being considered commercial engines being tested to a different standard.
Oh I agree, in reality any forced induction engine will likely be under-rated. A 430 hp diesel will dyno a lot healthier than a 430 hp gas. I was strictly explaining the theory behind it.
We should compare a diesel and gas that dynos the same peak hp. The diesel with an older 6 speed, and the gas with 10 spd. I bet at sea level they'd pull very close.RoyJ wrote:
dodge guy wrote:
Yes, better gearing will tow better. Glad you now understand!
And with enough gearing (10 spds), two engines of the same hp, one with double the torque, will perform IDENTICAL except right off the line.
I hope you understand that now.
I agree with you in principle but in every dyno test I have seen the diesels produce much more of their rated horsepower than the gas engines in the same vehicle. So, a diesel will frequently outrun a gas engine of the same rating. I haven't found any explanation for this and it is just a personal observation. It may have something to do with diesels being considered commercial engines being tested to a different standard.ShinerBock wrote:
if this 2020 truck is like all Fords I have owned, it will hit its governor at 95 mph.
I'm not sure what the max speed is limited to but I think it's either 105 or 110mph. My 2016 F150 will easily hit 103mph. Completely stock with no tuner 2.7 EcoBoost 4X4 with 3:55's.- I thought the only gas truck to come with a 4.30 with the new 10 speed was the Tremor due to it's 35" tires.
- Let's do some math, the Ford 10 speed has the following ratios:
Ratio: 4.6957 2.9851 2.1462 1.7690 1.5201 1.2700 1.0000 0.8536 0.6892 0.6357
From Ford's chart, the 7.3 makes above 400 hp from 4800 - 5800 rpm. In the first 6 gears, those rpm correspond to the following speeds, assuming 4.3 diff ratio and 33" tires:
1: 23 - 28 mph
2: 36.7 - 44 mph
3: 51 - 62 mph
4: 62 - 75 mph
5: 72 - 87 mph
6: 86 - 104 mph
With so many gears, there are very few gaps where the engine isn't making close to peak hp. In fact, from 51 mph and above, the engine is always making 400+ hp, at any speed from 51 - 104 mph.
The "lack of torque" of a big displacement gas engine isn't a concern at all with modern transmissions. At any reasonable towing speed, the transmission has a ratio that allow close to peak hp. dodge guy wrote:
Yes, better gearing will tow better. Glad you now understand!
And with enough gearing (10 spds), two engines of the same hp, one with double the torque, will perform IDENTICAL except right off the line.
I hope you understand that now.- That's a cool engine for sure. Nice power and torque ratings VS RPM's. Not giving up my Duramax though........................
parker.rowe wrote:
I guess people think just because something has pushrods its old outdated technology?
It is old but obviously not outdated. Lol
