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Max HP on stock internals

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California
#1
By chance does anyone know how much power the stock internals can handle? I’d love to build my fiesta to just push as much power as possible but not sure about building the block yet😅
 


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#2
It's just an opinion developed from years of reading posts about blown engines but I would pass anything requiring a larger capacity turbocharger. So plan on about 240-250 HP maximum. If you want more than that then spend the money to get a Mountune short block with forged internals. I'll also note that if you do increase the engine power to that 240 HP number you should also have a new "limited slip" differential installed in your transmission. Because that much power will be too much any stock width tires without the Traction Control kicking in. Yeah you might find some way to get 305's to sort of fit but you will end up with a very large turning radius due to tire rub issues. BTW I'm driving on 205/16 Firestone all seasons with a 50K life rating and my mostly stock Fist with it's increased cooling capacity and larger intake cooler is distinctly traction limited in 1st and 2nd gears.

I will also note that boosting power always ends up with a higher cost than anticipated. I have a 1985 Monte Carlo SS with a GMPP 383 under the hood. At present its producing 345 HP which is pretty much the limit that 2nd gear in the tranny can take, a prior built 350 produced over 400 HP and 2nd gear would take near 3 minutes to fully engage the only time I nailed it from the line. Anyhow that 383 can easily be bumped to over 500 HP with a simple cam swap and dusting the valve seal faces by 0.03 inches to provide clearance for the increased lift of the cam. I haven't done that for one simple reason, the transmission to handle that level of power costs roughly 12 thousand and the controller is another 4 thousand.
 


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Capri to ST

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#3
By chance does anyone know how much power the stock internals can handle? I’d love to build my fiesta to just push as much power as possible but not sure about building the block yet😅
Here's an article I think you will find helpful on that point. They go through the engine part by part and talk about how much power they think each one can handle, and which ones might need to be changed to reach their goal. Here's a description of their goal-
Here’s a look at the FORD EcoBoost 1.6L in detail... It’s our goal to build this 1.6L engine to thrive and survive at 400 whp.

https://dsportmag.com/the-tech/ford-ecoboost-1-6l-analysis-turbocharged-direct-injection-ccvtc/

Anecdotally, people here on the Forum describe going up to about 300 horsepower on stock internals without too much effect on reliability. That tracks with what the article says, which is that you can generally increase power by about 50% reliably.
 


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OP
Dohm
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Location
California
Thread Starter #5
Here's an article I think you will find helpful on that point. They go through the engine part by part and talk about how much power they think each one can handle, and which ones might need to be changed to reach their goal. Here's a description of their goal-
Here’s a look at the FORD EcoBoost 1.6L in detail... It’s our goal to build this 1.6L engine to thrive and survive at 400 whp.

https://dsportmag.com/the-tech/ford-ecoboost-1-6l-analysis-turbocharged-direct-injection-ccvtc/

Anecdotally, people here on the Forum describe going up to about 300 horsepower on stock internals without too much effect on reliability. That tracks with what the article says, which is that you can generally increase power by about 50% reliably.
Thank you so much for this! Time to spend hours reading and learning😂
 


OP
Dohm
Messages
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4
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California
Thread Starter #6
It's just an opinion developed from years of reading posts about blown engines but I would pass anything requiring a larger capacity turbocharger. So plan on about 240-250 HP maximum. If you want more than that then spend the money to get a Mountune short block with forged internals. I'll also note that if you do increase the engine power to that 240 HP number you should also have a new "limited slip" differential installed in your transmission. Because that much power will be too much any stock width tires without the Traction Control kicking in. Yeah you might find some way to get 305's to sort of fit but you will end up with a very large turning radius due to tire rub issues. BTW I'm driving on 205/16 Firestone all seasons with a 50K life rating and my mostly stock Fist with it's increased cooling capacity and larger intake cooler is distinctly traction limited in 1st and 2nd gears.

I will also note that boosting power always ends up with a higher cost than anticipated. I have a 1985 Monte Carlo SS with a GMPP 383 under the hood. At present its producing 345 HP which is pretty much the limit that 2nd gear in the tranny can take, a prior built 350 produced over 400 HP and 2nd gear would take near 3 minutes to fully engage the only time I nailed it from the line. Anyhow that 383 can easily be bumped to over 500 HP with a simple cam swap and dusting the valve seal faces by 0.03 inches to provide clearance for the increased lift of the cam. I haven't done that for one simple reason, the transmission to handle that level of power costs roughly 12 thousand and the controller is another 4 thousand.
Thank you for the info. I definitely think an LSD is on my top priority even just for stock because man is open diff annoying 😅 I would love to go absolutely crazy and push numbers nobody has heard on a Fist but I know it will take a longgg time and even more money🥲
 


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#7
Thank you for the info. I definitely think an LSD is on my top priority even just for stock because man is open diff annoying 😅 I would love to go absolutely crazy and push numbers nobody has heard on a Fist but I know it will take a longgg time and even more money🥲
If you want stupid powerful and fast off the line you'll have to toss the ST powertrain and adapt the body/frame to mount a Focus RS powertrain. You will also want to start with a Mountune 2.3 long block assembly and spend a good bit of time finding a turbo large enough for 600+ HP output. To do this you'll also need roughly 70,000 dollars of cash. for the work involved. Current local rumors in the supercar community is that there are two of these cruising in the Detroit area and one appears to be bone stock from the side profile. From the rear the tipoff is that the rear has been tubbed to carry 275 profile tires. Word is the sleeper likes to pick on Dodge Hellcats.
 


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san diego
#8
From what I have gathered I would not go over 340-350 HP on stock internals. But I would talk to who ever you choose to do your tune. They should know best. But safe is a term that the individual has to define themselves. Safe for me might not be safe for you.
 


WannabeST

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#9
By chance does anyone know how much power the stock internals can handle? I’d love to build my fiesta to just push as much power as possible but not sure about building the block yet😅
You should mention what the car is being used for. A track car, Drag car, highway car will all see different levels of abuse on different parts of the car.
My best advice from someone who enjoys driving more than building, Prepare the rest of the car for big power and enjoy the car in stock power. Then when the rest of you chassis is ready, throw in the built engine. If you want to push as much power as possible and do the engine first, you are just going to run into roadblock after roadblock.
 


OP
Dohm

Dohm

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Thread Starter #10
You should mention what the car is being used for. A track car, Drag car, highway car will all see different levels of abuse on different parts of the car.
My best advice from someone who enjoys driving more than building, Prepare the rest of the car for big power and enjoy the car in stock power. Then when the rest of you chassis is ready, throw in the built engine. If you want to push as much power as possible and do the engine first, you are just going to run into roadblock after roadblock.
I plan on doing canyon runs/highway runs. That being said building the chassis, like you stated, is probably a smart idea lol. Thank you for the advice!
 


rallytaff

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#11
I plan on doing canyon runs/highway runs. That being said building the chassis, like you stated, is probably a smart idea lol. Thank you for the advice!
Don't forget that you live in Kalifornia where smog checks or police will stop you for a hood up inspection and send you to a State ref which will be a bitch!
 


OP
Dohm

Dohm

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Thread Starter #12
Don't forget that you live in Kalifornia where smog checks or police will stop you for a hood up inspection and send you to a State ref which will be a bitch!
man dont remind me 😭
 


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