Top speed in each gear

[Brickell FIST]

I was just curious to find out the maximum speed in each gear. Also, what gear will the maximum speed be attained and what is that number? I am not sure if the car is limited from stock or becomes unrestricted with a AP.

 

[trahma]

Assuming 20.14" diameter (17" + (40mm*2)) and a 6700 RPM redline:

1st: 28
2nd: 51
3rd: 77
4th: 102
5th: 128
6th: 152

I calculated these using this calculator: http://www.apexgarage.com/tech/gear_ratios.shtml and specs from this page: http://www.edmunds.com/ford/fiesta/2014/road-test-specs1.html

 

[Hijinx]

Assuming 20.14" diameter (17" + (40mm*2)) and a 6700 RPM redline:

1st: 28
2nd: 51
3rd: 77
4th: 102
5th: 128
6th: 152

I calculated these using this calculator: http://www.apexgarage.com/tech/gear_ratios.shtml and specs from this page: http://www.edmunds.com/ford/fiesta/2014/road-test-specs1.html

Stock tire is 23.4"

 

[MacDubois]

Assuming 20.14" diameter (17" + (40mm*2)) and a 6700 RPM redline:

1st: 28
2nd: 51
3rd: 77
4th: 102
5th: 128
6th: 152

I calculated these using this calculator: http://www.apexgarage.com/tech/gear_ratios.shtml and specs from this page: http://www.edmunds.com/ford/fiesta/2014/road-test-specs1.html

Not quite, the tires are actually 23.4 diameter per tirerack/bridgestone. The 40 is aspect ratio, not mm. Overall diameter is (40% of 205mmx2) + 17 inches. My fuel cut is closer to 6500, so I used that.

Should be:
1st: 32
2nd: 58
3rd: 87
4th: 115
5th: 144
6th: 172

Top speed is somewhere in the high 130s, magazines report 137. No idea if it's limited.

 

[Ryephile]

Assuming 20.14" diameter (17" + (40mm*2)) and a 6700 RPM redline:

That's not how you calculate tire sizes. 40 in 205/40-17 is not millimeter, it's % of section width, which in this case is 205 * 40% = 82mm. However that's only theoretical, not a specific tire model spec.

Static tire diameter for the stock Bridgestone 205/40-17 is about 23.5", however loaded rolling effective diameter is about 22.76", which is 886 revs/mile.

From there you can calculate MPH vs. Gear vs. RPM. Given the torque plummet on the stock turbo FiST, most of the time you want to shift at 6250 RPM, but at 6750 RPM, the MPH per gear is:
1st = 32 MPH
2nd = 57
3rd = 88
4th = 116
5th = 146
6th = 173, with more power than stock turbo can give

 

[Ryephile]

Here's a screencap from my spreadsheet:

 

[Ryephile]

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.

 

[Hijinx]

Here's a screencap from my spreadsheet:

View attachment 9760

Can you do this for a 7400 redline?

 

[Zissou]

Okay, but what about reverse?

https://www.youtube.com/watch?v=-tulDW616IE

 

[Siestarider]

Stock spec top speed is in 5th, around 138.5 mph, drag limited. So if you want faster top end, either improve existing aero or add HP.

For example, lowering car 1" reduces frontal area and should add a little top end.

http://www.fiestastforum.com/forum/threads/5065-Virtual-Dyno-HP-Cd-frontal-area-and-Top-Speed copied and pasted address of a old thread about HP and top speed. For those of us who have big turbos, just in case you would rather calculate your top end than go to Mexico.

 

[wrongwheeldrive]

Top speed is somewhere in the high 130s, magazines report 137. No idea if it's limited.

I hit 135 somewhere in Wyoming. I cannot tell you if it is governed because there was no more road to play with. I can tell you that this car will get up to 120 fast but creeps up sloooooooooowly from there (in stock form). I wouldn't be surprised if 137 is the limit of what the car can reach stock. There just wasn't any power left! Also, the car feels scary light at that speed. The rear end wiggled all around while braking.

I hope to find a long empty stretch of road again to test with my Tune+ upgrades, if there's a governor I will find it!

 

[Rhinopolis]

At what rpm is it "safe" in the taller gears (5th and 6th) to run full boost? I understand not to lug the engine and then go full boost, but what is the magic rpm level where full boost becomes "safe" in those taller gears?

 

[15performanceblue]

I have had the speedo at 155+ in my stage 3 E40 tuned car. I looked down and it was a little past 155. I looked right back up. Not sure how much more it had, but I kept it floored for another good 10 seconds or so before letting off.
I was at 150 with my brother in law in the car with my old 93 tune.

 

[Brickell FIST]

Thanks for all the input. I live in Florida and like to know what speeds are max in each gear. Alligator alley any speed is obtainable. This car can be a bit sketchy. I like to know what the car is capable of. You guys nailed it. Thanks!

 

[Ryephile]

Here's a screencap from my spreadsheet:

View attachment 9760

Can you do this for a 7400 redline?

You can extrapolate it pretty quick. 1st gear is about 5 MPH per 1k RPM, 2nd is 8, 3rd is 13, 4th is 17, 5th is 22, 6th is 26 mph per 1k RPM. So the chart would expand to 7,000, 7,250, and 7,500 RPM like this:

1st, 2nd, 3rd, 4th, 5th, 6th
34, 59, 91, 120, 152, 180
35, 61, 95, 125, 157, 187
36, 63, 98, 129, 162, 193

 

[Ryephile]

At what rpm is it "safe" in the taller gears (5th and 6th) to run full boost? I understand not to lug the engine and then go full boost, but what is the magic rpm level where full boost becomes "safe" in those taller gears?

Safe? Safe for what? The ECU is always in full control of itself with regards to pre-ignition and knock and over-temp regulation, on top of targeting specific torque limits. If you want more torque from the engine, push the pedal further to the floor. If you're below the boost threshold RPM than you'll get not much torque. Downshift to the meat of the turbo's operational band, 3k to 5k RPM, and enjoy. Magic has absolutely nothing to do with the ECU strategy.

If you want to verify that big downpipe made a boost threshold improvement, the only effective datalogging will be to floor it at 1k RPM in 6th and wait for the spool-up. Obviously it'll take a while, but you're not damaging anything.

 

[Siestarider]

Safe? Safe for what? The ECU is always in full control of itself with regards to pre-ignition and knock and over-temp regulation, on top of targeting specific torque limits. If you want more torque from the engine, push the pedal further to the floor. If you're below the boost threshold RPM than you'll get not much torque. Downshift to the meat of the turbo's operational band, 3k to 5k RPM, and enjoy. Magic has absolutely nothing to do with the ECU strategy.

If you want to verify that big downpipe made a boost threshold improvement, the only effective datalogging will be to floor it at 1k RPM in 6th and wait for the spool-up. Obviously it'll take a while, but you're not damaging anything.

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.

 

[Rhinopolis]

Safe? Safe for what? The ECU is always in full control of itself with regards to pre-ignition and knock and over-temp regulation, on top of targeting specific torque limits. If you want more torque from the engine, push the pedal further to the floor. If you're below the boost threshold RPM than you'll get not much torque. Downshift to the meat of the turbo's operational band, 3k to 5k RPM, and enjoy. Magic has absolutely nothing to do with the ECU strategy.

If you want to verify that big downpipe made a boost threshold improvement, the only effective datalogging will be to floor it at 1k RPM in 6th and wait for the spool-up. Obviously it'll take a while, but you're not damaging anything.

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

 

[trahma]

Not quite, the tires are actually 23.4 diameter per tirerack/bridgestone. The 40 is aspect ratio, not mm. Overall diameter is (40% of 205mmx2) + 17 inches. My fuel cut is closer to 6500, so I used that.

Should be:
1st: 32
2nd: 58
3rd: 87
4th: 115
5th: 144
6th: 172

Top speed is somewhere in the high 130s, magazines report 137. No idea if it's limited.

Thanks for the correction. Exactly why I included my sources.

 

[Zormecteon]

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