ST-line build

[Plain Jane]

Had this idea of doing an OE+ build on our 2015 Fiesta SE hatch 5MT. By my understanding many parts off the ST will bolt up to the base NA 1.6 cars. Looking to make a comprehensive list on what exactly we can swap over, how much of an improvement they can be expected to make, and also where to buy the parts. Still compiling the list, so will be some time before things start moving, but if you'd like to chime in or offer ideas/suggestions I'm more than willing to hear it. This is my first Ford so am not deeply familiar with the platform yet

The first thing I'd like to do is snag the suspension off the ST as my rear shocks have begun to leak and they need the most attention. Sway bars and endlinks would be thrown in too and anything else that I may need to complete the package. Afterwards will go from there

 

[scotman]

Have you driven the ST version?

 

[Plain Jane]

Have you driven the ST version?

No, but all the reviews for it are overwhelmingly positive

 

[scotman]

Just the body pieces to replicate the appearance of the ST package would be over $1,500 dollars if you could find all of them used. That doesn't include the paint and installation cost.
I would clean up my basic Fiesta, maybe put some new rear shocks on it and then sell it and find a nice used ST Line Fiesta somewhere.
I am buying Fiesta ST parts frequently. They are not inexpensive used. They are crazy expensive new!
My favorite example of how expensive ST parts are is the tiny little "peel and stick" ST emblem in the front grille panel. That tiny part is over $40.

 

[Plain Jane]

Interesting. I wasn't considering changing up the body unless I had to to fit the rear catback. So would you suggest abandoning the project and going aftermarket or forget the whole thing entirely? I like the car, I like the fuel economy and I love the handling. Selling it to buy another is not high on my list of options, I just wanted to spruce it up a little.

 

[Rowdy09]

Are front ends the same on a hatch as the sedan? I know the rears are not

 

[scotman]

The front sheetmetal is identical.

 

[scotman]

I own both versions of the Fiesta. I like the fuel economy of the basic fiesta. I like the performance and driving dynamics of the ST. I do not like the insurance costs of the ST! My cost of coverage for a year on the ST has recently increased to over $2,300 a year. That's with NO tickets, NO accidents and NO glass breakage claims. That is close to what i was paying for a Mustang convertible i had less than seven years ago.

 

[Plain Jane]

I own both versions of the Fiesta. I like the fuel economy of the basic fiesta. I like the performance and driving dynamics of the ST. I do not like the insurance costs of the ST! My cost of coverage for a year on the ST has recently increased to over $2,300 a year. That's with NO tickets, NO accidents and NO glass breakage claims. That is close to what i was paying for a Mustang convertible i had less than seven years ago.

Rough. It's about $1,000 CAD/y for our Fiesta and base 2014 Civic (each) with reasonable coverage in western Canada. My old Eclipse was even less and that had ~300hp

 

[scotman]

Interesting. I wasn't considering changing up the body unless I had to to fit the rear catback. So would you suggest abandoning the project and going aftermarket or forget the whole thing entirely? I like the car, I like the fuel economy and I love the handling. Selling it to buy another is not high on my list of options, I just wanted to spruce it up a little.

Selling the one you have might be the cheapest way to get what you really want and would enjoy more.
The Fiesta is a digital car. By that i mean that it is CANbus networked and has a build configuration when assembled that creates a lot of problems for anyone who wishes to change many features in the car. The engine processor is locked, so performance upgrades are not economically possible. Even if you could remap the engine, the basic Fiesta manual transmission has very unfavorable gearing for any performance that might have been gained. The ratio of third gear is very poor for performance purposes.
The disc brake rear axle assembly is do able. And the rear disc brakes are easily serviced for pad changes compared to the drum brakes on the basic fiesta. I have found that the rear pads will have less than half the lifespan of the shoes on the drum brake equipped basic fiesta. It's not my driving style that lead me to that conclusion, its the torque vectoring and stability controls that are very different between the two versions of fiesta. I don't know if it's the system calibration or the material specs and design of shoes versus pads. But the ST version has a strong appetite for rear pads and rotors. You would need to make the deciding call on the value of the disc brake upgrade for yourself.

 

[Plain Jane]

Selling the one you have might be the cheapest way to get what you really want and would enjoy more.
The Fiesta is a digital car. By that i mean that it is CANbus networked and has a build configuration when assembled that creates a lot of problems for anyone who wishes to change many features in the car. The engine processor is locked, so performance upgrades are not economically possible. Even if you could remap the engine, the basic Fiesta manual transmission has very unfavorable gearing for any performance that might have been gained. The ratio of third gear is very poor for performance purposes.
The disc brake rear axle assembly is do able. And the rear disc brakes are easily serviced for pad changes compared to the drum brakes on the basic fiesta. I have found that the rear pads will have less than half the lifespan of the shoes on the drum brake equipped basic fiesta. It's not my driving style that lead me to that conclusion, its the torque vectoring and stability controls that are very different between the two versions of fiesta. I don't know if it's the system calibration or the material specs and design of shoes versus pads. But the ST version has a strong appetite for rear pads and rotors. You would need to make the deciding call on the value of the disc brake upgrade for yourself.

So a rear disc swap on a base wouldn't have the excessive pad wear issue? Are the rear discs vented? What would you estimate the cost of the rear subframe?

 

[scotman]

I think that the pad wear issues would be close to the same. The rear disc brakes are not vented, its one solid disc. The rear axle beam assembly is bolted into the body structure. Same as the basic fiesta

 

[Rowdy09]

The front sheetmetal is identical.

So I could put a ST front bumper on my se?

 

[scotman]

If you have several hundred dollars, sure. But It won't serve any functional purpose. In terms of a modification, it would add less bang for your buck than the shot of whipped cream on top of a hot chocolate that some places are charging an extra ten cents for if you request it.