FIST Stock Turbo Max PSI, where does it get dangerous?

[TalkToTheFiST]

Hello all, i had a fairly simple (i hope) question. I read the stock tunes for the FIST have the turbo somewhere around 21psi, although that's only from 3rd on, in 1st and 2nd it's limited to 19psi. Is this true and, what happens if you increase the PSI, will that increase power at the cost of increased pressure in your engine?

If the above assumptions are true, at what point does the PSI hit a critical mass and start to do damage? I would assume the stock tune PSI is on the conservative side, how far can we push it and is there anything that should accompany more pressure, like a better FMIC? Im very new to automotive and tuning (and forced induction) and just trying to get a feel for how this all works.

 

[Hypergram]

I'm not sure about the specific numbers, but I do know torque is electronically limited in first and second gear to reduce torque steer and shredding tires. This can be disabled though without causing any damage as part of a tune I believe. A new intercooler will reduce temps and will obviously help quite a bit. Apparently, the stock IC is pretty garbage. Sorry, I can't answer your other questions. I simply don't know the answers. I'm sure someone will come in soon though.

 

[RubenZZZ]

My understanding is that the factory reduced boost in 1st and 2nd to avoid driveline damage warranty claims. Also helps control torque steer.

Cobb's OTS and any flash tune will allow full boost in all gears (really wakes up the car!).

The turbo is tiny and boosting high psi from the factory. An aftermarket intercooler helps keep the air temps down specially when boosting past factory levels.

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[TalkToTheFiST]

I'm not sure about the specific numbers, but I do know torque is electronically limited in first and second gear to reduce torque steer and shredding tires. This can be disabled though without causing any damage as part of a tune I believe. A new intercooler will reduce temps and will obviously help quite a bit. Apparently, the stock IC is pretty garbage. Sorry, I can't answer your other questions. I simply don't know the answers. I'm sure someone will come in soon though.

My understanding is that the factory reduced boost in 1st and 2nd to avoid driveline damage warranty claims. Also helps control torque steer.

Cobb's OTS and any flash tune will allow full boost in all gears (really wakes up the car!).

The turbo is tiny and boosting high psi from the factory. An aftermarket intercooler helps keep the air temps down specially when boosting past factory levels.

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Hi guys. Ok makes sense, i was just looking into some of the aftermarket boost tuners out there. I will eventually get an IC upgrade but it will be later this year, just finalizing what i wanted to do in the meantime. I know people recommend the COBB AP but im not having much luck finding one at a decent price used, which is making the SCT x4 look very tempting. It's just a matter of if it has enough tunes offered, free or at comparable prices to the competition.

 

[Ford ST]

Patience is a virtue. The Cobb tuner is by far the best. Just wait and save money for it. You can do as you wish, but no one can give you advice on a tuner no one uses.

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[RubenZZZ]

Hi guys. Ok makes sense, i was just looking into some of the aftermarket boost tuners out there. I will eventually get an IC upgrade but it will be later this year, just finalizing what i wanted to do in the meantime. I know people recommend the COBB AP but im not having much luck finding one at a decent price used, which is making the SCT x4 look very tempting. It's just a matter of if it has enough tunes offered, free or at comparable prices to the competition.

Believe me, I REALLY wanted to use an SCT or even Diablo tuner, but the truth is the Cobb is just favored among tuners.

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[TalkToTheFiST]

Believe me, I REALLY wanted to use an SCT or even Diablo tuner, but the truth is the Cobb is just favored among tuners.

Sent from my LGLS992 using Tapatalk

Will it matter if i never go past a OTC or canned tune? I know for sure im going to get a tune kit and by the end of the year i will get a better FMIC, but i can't say how long or how far i will go after that, depends on savings. And i don't do track days or anything like that, im just a guy with a fist for a daily driver looking for some more power. I don't think i will ever contact a tuner for a custom.

Ditto for some of the other stuff like readings and graphs ect, if i ever get to that point it will be many years down the road. For surface use is the COBB still that much better?

 

[Spork1569]

Believe me, I REALLY wanted to use an SCT or even Diablo tuner, but the truth is the Cobb is just favored among tuners.

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I feel finding a tuner for the other brands would be pretty difficult of a task in of itself.

While one can use the OTS maps for those other tuning devices, when you want to upgrade further are there even any reputable tuners for those other brands? I wouldn't want to trust that task to just anybody.

 

[Spork1569]

Will it matter if i never go past a OTC or canned tune? I know for sure im going to get a tune kit and by the end of the year i will get a better FMIC, but i can't say how long or how far i will go after that, depends on savings. And i don't do track days or anything like that, im just a guy with a fist for a daily driver looking for some more power. I don't think i will ever contact a tuner for a custom.

Ditto for some of the other stuff like readings and graphs ect, if i ever get to that point it will be many years down the road. For surface use is the COBB still that much better?

It's probably better to have the reliability and flexibility of the COBB and not need it, rather than need it and not have it if you choose another route.

My first mod was a simple RMM, I barely even knew how to change my own oil at that point. Never in a million years did I think I'd be this far into modding this car.

Im glad I bought the AP because as I grew more comfortable modding I could always have the flexibility to try this tuner or that tuner, run 91 or 93 or even ethanol tunes.

I didn't see myself going this far down the rabbit hole but I have no regrets, modding and driving this car is one of my favorite hobbies now. Your mindset too can change down the road and I say why limit yourself now when for the price of a new SCT you can find a good deal on a Cobb that'll let you grow if you decide to get bit by the mod bug down the line.

If you don't end up using it the Cobbs hold value really well and are always being sold secondhand, idk if I can say the same for the rest of the tuning devices. So if worst comes to worst and you find that none of it is for you, you'll at most only lose a few bucks as someone will always be searching for an AP to buy.

 

[Hypergram]

If you don't want the AP anymore I'll buy it off you lol. I would recommend looking at Stratified, they have a package which includes a new AP and a custom-ish tune for $550, which is the same price as a new AP from COBB without a tune. Here's the link. There's a lot of customization so check it out!

http://www.stratifiedauto.com/index.php?main_page=product_info&cPath=117_121&products_id=300

 

[Sprinkle_Star]

You ask some really good questions. I don't know much about tuning, but it's fun to read about.

 

[RubenZZZ]

Will it matter if i never go past a OTC or canned tune? I know for sure im going to get a tune kit and by the end of the year i will get a better FMIC, but i can't say how long or how far i will go after that, depends on savings. And i don't do track days or anything like that, im just a guy with a fist for a daily driver looking for some more power. I don't think i will ever contact a tuner for a custom.

Ditto for some of the other stuff like readings and graphs ect, if i ever get to that point it will be many years down the road. For surface use is the COBB still that much better?

I wanted a custom tune from the start. From what I read, the Cobb OTS tunes were very mild. That and the tuner was like $500+ new. Used SCT3s could be found for like $150. I figured most Mustang pro-tuners could tune my Fiesta with an SCT... Not the case! You need a SCT4 model, and very few tuners will want to tune the car. They kinda brush you off, or just tell you no thanks.

I looked into Diablosport, but the cars being tuned with them were having issues. Never followed up, but nobody talks about them anymore...

In the end, Cobb turned out to be the best choice.



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[TalkToTheFiST]

I wanted a custom tune from the start. From what I read, the Cobb OTS tunes were very mild. That and the tuner was like $500+ new. Used SCT3s could be found for like $150. I figured most Mustang pro-tuners could tune my Fiesta with an SCT... Not the case! You need a SCT4 model, and very few tuners will want to tune the car. They kinda brush you off, or just tell you no thanks.

I looked into Diablosport, but the cars being tuned with them were having issues. Never followed up, but nobody talks about them anymore...

In the end, Cobb turned out to be the best choice.



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Funny you mention that bc i found a diablo sport last night for $200 on ebay. Looked tempting for an actual tuner but i found an old thread here where multiple people had warning lights and issues with the turbo not engaging or something. So yea not doing that. So Cobb seems to be the one, but im not having luck finding it used, which brings me to the thread topic here actually.

I was reading another thread here from a couple years ago, HERE. The item in question is called a sprint booster, which piggybacks on the boost pressure sensor. In essence it lies to the ECU convincing it to up the boost by however much. In the thread a forum member MaestroMaestro is skeptical, ends up buying one and then explains how it does actually work.

This was one reason i started asking about stock boost. If tunes increase the boost moderately on a stock turbo, then a piggy back should be able to also. The catch with the sprint booster is the car was always trying to counter the boost pressure sensor reading bc its not the only sensor. Which is where i found a solution.

I found something called race chip. It basically does what the sprint booster does but does so with the manifold pressure sensor also. I've found several videos of people reviewing them and they work. My guess is very similar to stage 2 kits, you will want an upgraded FMIC since you are increasing boost.

Any thoughts on these kinds of kits?

 

[Booster]

26psi to avoid overspinning.

 

[danbfree]

I think we've touched on this in your other thread, but I like to go by Dizzy's max target PSI: 24.75 on pump, 26.25 on e30. It's just a personal opinion thing as far as the pump limits, and while I appreciate Alex of Stratified's overall knowledge, I have personally seen how Jason described that going past 24.75 on pump fuel has zero benefits and can actually hurt performance and efficiency a bit. Since ethanol has a cooling effect, that's why it's totally safe and effective to push it a bit more on e30 tunes. But also, timing plays big into it, some tunes actually add more timing (which adds power and heat of it's own) while keeping the boost down a touch. For example on my e30 tune, it uses only 2.5 degrees of added timing but uses the full 26.25 max boost target while on my e50 tune I see 26 psi max and up to 5 degrees of added timing but only hit that occasionally, it seems adaptive based on conditions more. To be clear, an e50 tune is just for easier math when mixing, it doesn't add much more cooling effect or octane that a stock turbo can even use... But also base timing plays into it as well, the higher the base timing is, the smoother power you get with only a little more added in later but can up your coolant temps a bit at idle.