2 final drive ratios- why didn’t the fist use this?

[Stkid93]

As some of you may know, it’s become more and more common to have 2 final drive ratios these days. Typically gears 1-4 have their own final drive and gears 5-6 have their own. Having 2 final drive ratios allows the car to have much more aggressive 1-4 gears, while allowing gears 5-6 to be highway gears. Some of the cars that do this include

-GR corolla
-focus st
-focus rs
-mazdaspeed 3

So my main questions are

1) besides cost, why do you think they didn’t they have 2 final drives with the fist? (Like I said above, I’m going to go ahead and assume the reason they didn’t have 2 final drives on the fiesta st was cost, but I’m not convinced cost was the deciding factor)

2) how do you think 2 final drives would affect the fist, do you think it would make it a better or worse car?

3) if there was a modification on the market that allowed us to change to a 2 final drive ratio set up. Assuming it was reasonably priced, would you buy it?

.

 

[Dialcaliper]

Dual final drives (separate countershafts on the ring gear) are usually used to a) make a transmission more compact, and b) Allow the higher and lower ratios to use more equal size gears, which is a way to make a transmission to handle more power without making the whole transmission physically much larger.

Basically, any time you’ve got to mesh a little tiny gear with a big gear to get a desired ratio, especially in the lower gear ratios, you have a much weaker combination, as the small gear has less material to distribute the load (you can only add a limited amount of material to the small gear to make it stronger, without also making the large mating gear wider. Adding a second countershaft with different final drive means you don’t need as wide a spread of gear sizes and ratios.

The FiST didn’t get one for plenty of reasons. Increased cost probably being the first reason, and then the fact that it’s not dealing with a lot of power or moving a heavier vehicle, both of which put more load on the transmission.

Given the fact that the IB6 seems to be fairly reliable and the market demographic doesn’t mind (and likes) a tight ratio transmission, I’m not seeing a lot of advantage to justify the cost.

Ford didn’t need a shorter 1st gear because the turbocharger already adds enough low end that 1st and 2nd are traction/torque limited, and they were able to extend the top end by adding a 6th gear and taller final drive over the base Fiesta

All of the other cars on your list are either AWD (not traction limited), or are heavier than the FiST.

The Getrag MMT6 transmission in the Focus ST is also shared across a wider variety of vehicles some of which are quite heavy and/or have a lot of power. For example the Transit and Mondeo, and it’s also designed for an AWD variant used in the Focus RS as well a range of Volvo vehicles (S80, V70 including R models listed as a different code).

The Getrag IB6 in contrast is simply the next “step down” in size only used with smaller engines and nothing larger than the older Mondeo and older UK Focus Mk2 ST models

The Mazdaspeed 3 transmission also shares an AWD variant in the Mazdaspeed 6, and I suspect is also used in a number of other vehicles.

The beefier transmission simply wasn’t needed in the FiST and would have also driven MSRP up, probably by several thousand dollars.

 

[Stkid93]

Wow, that was an impressive breakdown. Out of curiosity are you some kinda of mechanic engineer or transmission guru? You seem to know a ton about this stuff. More than the average Joe for sure

 

[M-Sport fan]

They sell Transits in Europe/rest of world with manuals??

I've never even heard of one here in the states, let alone have ever seen one.

 

[Stkid93]

I also thought that was interesting but hey. They make giant diesel pick ups with a stick shift. The srt-10 was a giant dodge pick up with a viper v10 and a stick shift. And people have swapped manuals into minivans for fun. So it’s not impossible I guess. My personally I love that, I personally think every car should have the option for a stick. Especially all the new super cars. That don’t even offer that as an option anymore which immediately turns me off. If I’m buying a super car I want a 6 speed. That’s why the 911r is so sought after. It’s a gt3rs with a stick. And they are worth a ton of money. Although I’m not sure how many people want a stick shift transit van. I imagine the take rate would be very low.

 

[Intuit]

Wow, that was an impressive breakdown. Out of curiosity are you some kinda of mechanic engineer or transmission guru? You seem to know a ton about this stuff. More than the average Joe for sure

Obviously has an engineering background.

Ford didn’t need a shorter 1st gear because the turbocharger already adds enough low end that 1st and 2nd are traction/torque limited, and they were able to extend the top end by adding a 6th gear and taller final drive over the base Fiesta

To get off the line, I have to slip the clutch at much higher RPMs on this 16 valve 1.6L engine, than I did on a prior 8 valve 1.9L (82 mm × 88 mm (3.23 in × 3.46 in)) engine. The the 1.9L does have more stroke, but I always assumed that the tiny displacement, was the largest factor in their decision to add the sixth gear before one.

For comparison it may be interesting to see what they did with the transmission on the later generation 1.5L 3 cylinder engine.

 

[Stkid93]

I know the tranny on the 1.5 fist is way more aggressive. The final drive is 4.3, with more aggressive gearing. Carwow did a drag race comparison between the 1.6 fist and the 1.5 fist and despite extremely similar power numbers the 1.5 pulled away pretty easily due to the gearing advantage. The 1.5’s top speed is way lower but again, who really needs to go 170+ in a fiesta.

 

[Fusion Works]

Fiesta ST 2018-20
6th 0.651
5th 0.775
4th 0.971
3rd 1.290
2nd 1.952
1st 3.583
Reverse 3.333
FDR 4.313

While numerically different, the gearing is going to behave pretty much the same. The 1.5 turbo Fiesta ST uses a tire that is 1in larger in OD, that requires different gearing to get the acceleration back.

The numbers though are pretty much the same. The 18 and up car are slightly shorter than the US model 1.6 cars about 6%. Thats pretty much in the noise.

 

[Stkid93]

I don’t honestly know anything about how tire size affects gearing. I obviously know that putting different size tires will make your speedo in accurate. So it obviously affects it. I just don’t know how much. For example, I don’t know how much 1 inch in OD affects acceleration. But I do know the newer 1.5 fists are pretty much identical in total power output. The shape of the curve and where they make torque will be slightly different. But despite the almost identical power out the 1.5 pulled away very easily. Not only from a dig. But from a roll race as well. I know the newer fists come with an optional lsd.

I don’t know how the 1.6 would drive if it has the more aggressive gearing from the st200/mark 8 fiesta. I imagine the gears would be incredibly short considering the 1.6 cars already require a shift to 3rd for 0-60 and 5 gears to get thru a quarter mile. So more aggressive gears would require a bunch more shifting. But, it would also increase the torque output at the wheels by about 20-30%. Assuming you can put the power down that’s a very significant difference. Hence why the 1.5 with the aggressive gearing pulled away so easy from the 1.6. And Obviously this isn’t a huge problem as ford engineers made it work without having ridiculous wheel spinning.

I would I personally be super interested in driving a stock turbo fist with the 4.3 final drive just to see what it’s like. I think the gearing they chose for the 1.6 fists was more for fuel economy rather than performance. Because 6th gear is about the tallest 6th gear you will find and allows the fist to get up to 170 mph+ assuming it has enough power to power through the super tall 6th gear.

Had they gone with 2 final drives, they wouldn’t have needed to make 6th so tall. Which would help with people lugging their motor and experience lspi as well.

 

[Fusion Works]

I have a 4.06 final in my car and its better than stock, but its not "earth shatteringly" different. That is ST200 gearing.

Stop looking at the actual numbers of the gearing. It all works together. So a 4.3 final with a .651 works out to a 2.8 gear at the wheel, the 1.6 cars have a 2.6 gear at the wheels with a .69 6th gear. The Focus SVT with a triple shaft transmission 2.88/4.25 final drive has a 3.0816 sixth gear. So no the Fiesta 6th gear isn't that tall.

People lugging their engine has nothing to do with gearing and everything to do with the American mentality for driving at low rpm. Add to that the goofy ass shift light Ford put in these cars that was coded for mileage.

 

[Fusion Works]

BTW Volvo used a .622 6th gear in Europe. Even longer than what we have.

 

[Stkid93]

@Fusion Works

How did you get that final drive? Do you have an actual st200? Cause those are very rare.

I thought the only aftermarket modification available for our final drive was the 4.3 final drive. Do they also have a 4.06 available somewhere?

 

[M-Sport fan]

BTW Volvo used a .622 6th gear in Europe. Even longer than what we have.

Yes, apples to kiwis, due to almost 400 lb.ft. of torque to the rear wheels right from the factory, but the T56 in my '00 Z28 had a .50 sixth.

WHY it was able to get over 32 MPG on the highway.

 

[Fusion Works]

Nothing like cruising at 90 at 1800rpm. LOL.

BTW, that Volvo V40 has a 1.6 turbo engine with the same transmission in our Fiesta. Not Apples to Kiwis.

 

[Dpro]

@Fusion Works

How did you get that final drive? Do you have an actual st200? Cause those are very rare.

I thought the only aftermarket modification available for our final drive was the 4.3 final drive. Do they also have a 4.06 available somewhere?

it actually came here in the Fusion Ecoboost with manual trans. If you had the part number you could order it from Ford . Though I would not hold my breath on them being able to get it given Ford propensity for discontinuing parts for cars of late. Otherwise you try sourcing it in the yards one othe4 forum member did that. I wanted it initially but ya sorta of a lot of trouble to find/ get. I do feel with how low our 1st is already a 4.3 would just make it completely useless.
YMMV

 

[Fusion Works]

SHHHHHH, stop sharing the secrets. I can't find anything that suggest there are any serviceable parts inside those Fusion Transmission. I had to buy my own trans from a junkyard and then take the damn thing apart. I agree 1st is entirely too short. My preferred trans would look something like the Mk8 ST, with some slightly different ratios to tighten it up some more.

3.25
2.098
1.5
1.2
1.000
0.850
Something along these lines.

 

[M-Sport fan]

Nothing like cruising at 90 at 1800rpm. LOL.

BTW, that Volvo V40 has a 1.6 turbo engine with the same transmission in our Fiesta. Not Apples to Kiwis.

I was referring to my comparing a 5.7 liter V8 ride to our 1.6T rides, and NOT your comparison above.

Just pointing out that there were/are some super overdrive top gears in some gearboxes out there, that's all.

 

[Fusion Works]

400lbft at idle lets you get pretty long, especially like a Vette which is pretty slick. It can easily get away with those long over drives.

 

[Stkid93]

I’m on stock turbo e30 and I’m just looking for a little more. personally would love a fist with 280-300 horsepower and 360-400 torque, I think that would make it an almost perfect car. Bigger tires and lsd on top of that additional power would make it perfect in my mind. I don’t think anyone would ever need more than that in a 2700 lb car. I had a neon srt4 that made 325/385 at the wheels 2900-3000 lbs or so and that thing was insane. The only race I ever lost in it was to a 2001 twin turbo s4 with rs6 turbos making 600 wheel all wheel drive.

 

[Fusion Works]

There will always be someone faster, so I don't worry about that part.

A S280 makes the car about right. That turbo doesn't fall off like the OE turbo. That kinda fixes the main grip with the car.