Top speed in each gear

[Ryephile]

I strongly disagree on behalf of engines everywhere. Flooring anything in a high gear at low rpm is one of the few ways I know to deliberately damage your car. Direct injection plus turbo happens to be the setup that is at most risk of damage by doing this.

That would be changing the context rather strongly. We're talking about EcoBoost engines and their excellent LSPI strategy. Even then, compare the EcoBoost's to the BMW B-series TGDI Valvetronic engines. They have a torque shelf that starts at 1250 RPM.

research low speed pre ignition to have a gram of reference of what I am referring to

That's what I included in my previous reply. I recommend giving it another read, along with Cobb's Ford Tuning Guide if you don't already have ATR. If there's an emotional fear of you pushing the pedal to the floor based on previous cars, it's simply not a relevant response in the context of this engine. If you want a number, then according to ATR's examples the LSPI risk significantly drops off above 2k RPM, which also correlates to a significant rise in requested torque. Note that the ECU limits your torque request at low RPM. What your foot does and what the ECU deems safe is predetermined.

 

[Ryephile]

All interesting calculations, but they omit slip. The tires don't achieve perfect traction.

It's not meant to be complete, just amusing. It also doesn't include aero drag.

 

[Rhinopolis]

That would be changing the context rather strongly. We're talking about EcoBoost engines and their excellent LSPI strategy. Even then, compare the EcoBoost's to the BMW B-series TGDI Valvetronic engines. They have a torque shelf that starts at 1250 RPM.




That's what I included in my previous reply. I recommend giving it another read, along with Cobb's Ford Tuning Guide if you don't already have ATR. If there's an emotional fear of you pushing the pedal to the floor based on previous cars, it's simply not a relevant response in the context of this engine. If you want a number, then according to ATR's examples the LSPI risk significantly drops off above 2k RPM, which also correlates to a significant rise in requested torque. Note that the ECU limits your torque request at low RPM. What your foot does and what the ECU deems safe is predetermined.

Cool, I'll give it a look.

 

[Sourskittle]

Don't fool yourself... There are limits as to what the ecu can do to save you.
(Not mine, its a friends, no story behind it ).

 

[IronMaiden]

173 is theoretical top speed, yes? Even without a limiter, at what point can the car just not push the wind out of the way anymore? Let's assume there is no head wind, at a stand still start, on a perfectly level road.

 

[Hijinx]

173 is theoretical top speed, yes? Even without a limiter, at what point can the car just not push the wind out of the way anymore? Let's assume there is no head wind, at a stand still start, on a perfectly level road.

Depends on how much power you've got.


Sent from my iPhone using Tapatalk

 

[enamelizer]

And for fun, here's a tractive force to the contact patch per gear (in Lbf) for a stock FiST with stock 205/40-17 tires, based on the SAE published engine curves.

View attachment 9761

Wait, it isn't 3rd that pulls the hardest? lol =D

http://www.fiestastforum.com/forum/threads/12419-What-gear-pulls-the-hardest

 

[brbauer2]

All I know is I can get to 60 MPH in 2nd gear with a Stratified E-Tune before the car protects itself. Makes 0-60 times look better without that shift to 3rd.

 

[Ryephile]

Wait, it isn't 3rd that pulls the hardest? lol =D
...

The graph didn't account for the stock tune's torque limiters in 1st and 2nd. In real life, the actual accel g in 1st, 2nd, and 3rd is probably fairly similar.