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Discussion Starter #1 (Edited)
am I wrong in thinking overboost was 14sec? and never heard mention of reset times
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the over-boost function on the Focus RS lasts 20 seconds, and if you shift or lift off the throttle and then reapply it, the timer resets again for another 20 seconds, says Ford spokesman Paul Seredynski
 

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A more expanded quote of the relevant section:

Ford is able to generate such prodigious power from a relatively small four-cylinder engine in the Focus RS by using an all-new, twin-scroll turbocharger and a larger compressor that are continuously “over-boosted” to run at higher-than-normal pressures. In most cases where a turbo-charged engine features an over-boost function like this, it is only temporary and the additional power it generates is not necessarily factored into the engine’s official power rating.

But the over-boost function on the Focus RS lasts 20 seconds, and if you shift or lift off the throttle and then reapply it, the timer resets again for another 20 seconds, says Ford spokesman Paul Seredynski. Thus, the over-boost function is practically permanent, allowing for the Society of Automotive Engineers to officially rate the Focus RS’s 2.3-liter EcoBoost engine at 350 hp and 350 pound-feet of torque.
Interesting that it's the overboost that qualifies the engine for the 350 hp rating, I wonder what stock horsepower is sans overboost?
 

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A more expanded quote of the relevant section:



Interesting that it's the overboost that qualifies the engine for the 350 hp rating, I wonder what stock horsepower is sans overboost?
Curious about this too. Power figures without over-boost.

Also curious how long the motor is going to last before I blow it up 😅
 

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This does not sound like good news to me. If overboost only functions at full throttle, and most street driving is done at partial throttle, but the engine is say ... 315 hp instead, then it will drive MOST of the time like a 315 hp car.
 

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Some official figures would be nice. Ford is definitely not advertising this and it has me worried that the RS is going to perform a lot closer to the Golf R or STI in day to day driving than the 350hp figure would have us believe. I'm not going to cancel my order over it, but I'd still like to know what we are really getting.
 

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Discussion Starter #6
This does not sound like good news to me. If overboost only functions at full throttle, and most street driving is done at partial throttle, but the engine is say ... 315 hp instead, then it will drive MOST of the time like a 315 hp car.
no stock car will get full boost without going wot
only way to do that is with an aftermarket boost controller or maybe an ecu tune.

this is not unique to the RS
 

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no stock car will get full boost without going wot
only way to do that is with an aftermarket boost controller or maybe an ecu tune.

this is not unique to the RS
I'm aware of that, and that's not what I said. What I'm saying is that a boosted car with say 600 horse is going to be different at 30% throttle than a car with 250 horse at 30% throttle. So it goes to reason the same could be said about two cars with a smaller difference.

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I'm aware of that, and that's not what I said. What I'm saying is that a boosted car with say 600 horse is going to be different at 30% throttle than a car with 250 horse at 30% throttle. So it goes to reason the same could be said about two cars with a smaller difference.

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You can't make those comparisons without factoring in engine displacement, FI type/size, gearing, weight, etc. etc.

We really need more info on what load, gearing, speed variables affect the overboost function.

Nonetheless, I agree that this may cause a decrease in non-WOT performance. However it should be easily remedied with a tune :cool:
 

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This does not sound like good news to me. If overboost only functions at full throttle, and most street driving is done at partial throttle, but the engine is say ... 315 hp instead, then it will drive MOST of the time like a 315 hp car.
If you are using 20% throttle then you will notice absolutely zero difference between the normal and overboost modes.

The only time this will affect anything that I can see if top speed runs. Most of the gears won't last at WOT for more than 20 seconds, only the top gears. The 350HP isn't going to be there all the time. Neither is 300. Or 250. Or 200. Or 150. So anytime the car needs to make 350HP (mid-high RPM with high throttle %) it will make as much as it can.
 

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no stock car will get full boost without going wot
only way to do that is with an aftermarket boost controller or maybe an ecu tune.

this is not unique to the RS
Even then it will only hit full boost if throttle position demands it. I can bring my boosted cars to near redline with no boost by doing so very gently.
 

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You can't make those comparisons without factoring in engine displacement, FI type/size, gearing, weight, etc. etc.

We really need more info on what load, gearing, speed variables affect the overboost function.

Nonetheless, I agree that this may cause a decrease in non-WOT performance. However it should be easily remedied with a tune :cool:
This. It's the same motor. If normal boost is 20psi where it makes 315hp and overboost at 23.2psi or whatever it is makes 350, both will hit say 200hp at 10psi, which it'll be at regardless.

Can't really compare that to 30% throttle at 3,000RPM against a GTR or any motor that's different. They are simply allow higher boost than originally intended and limiting it's usage somewhat. This conversation is only important for those who plan to be in overboost settings (20-23.2psi or whatever "normal" is) for more than 20 seconds. It doesn't change how the car will drive around town at all.
 

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I'm not sure I understand the point of overboost if it resets after lift off. Even on long straights I've never been WOT for 20s. Under what circumstance would you possibly exceed 20 seconds of WOT? The only thing I can think of is trying to do a 6th gear pull? who does that though? It would make more sense to me if they said the monitored engine coolant temp / oil temp and lowered boost at extreme temperatures, but then I guess that wouldn't be very good advertisement material.
 

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I'm not sure I understand the point of overboost if it resets after lift off. Even on long straights I've never been WOT for 20s. Under what circumstance would you possibly exceed 20 seconds of WOT? The only thing I can think of is trying to do a 6th gear pull? who does that though? It would make more sense to me if they said the monitored engine coolant temp / oil temp and lowered boost at extreme temperatures, but then I guess that wouldn't be very good advertisement material.
The name is also deceiving in a way because that is exactly what the ECM does. These vehicles are all TQ targeting based and you will see a big difference in max boost pressure depending on intake temps. You could easily see more boost pressure under normal aggressive driving on a very hot day, compared to a very cold day hitting overboost. It goes back to the marketing thing, and makes it a lot easier to state 20 secs of overboost, something everyone should be able to grasp simply.
 

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This. It's the same motor. If normal boost is 20psi where it makes 315hp and overboost at 23.2psi or whatever it is makes 350, both will hit say 200hp at 10psi, which it'll be at regardless.

Can't really compare that to 30% throttle at 3,000RPM against a GTR or any motor that's different. They are simply allow higher boost than originally intended and limiting it's usage somewhat. This conversation is only important for those who plan to be in overboost settings (20-23.2psi or whatever "normal" is) for more than 20 seconds. It doesn't change how the car will drive around town at all.
I think we are talking apples and oranges here. You are comparing the Focus RS with 315 (guessing at this number due to some early information) hp to the Focus RS with 315 hp AND 350 hp overboost. I am comparing the Focus RS with this setup (315 hp w/ 20 sec overboost for 350 hp) vs a Focus RS with a PERMANENT 350 hp. They would be tuned differently, making it perform differently at all RPM. It would be a better accelerating vehicle at 30% throttle with a 350 hp tune than it will be with a 315 hp tune with 350 hp overboost. I'm not trying to compare it to a GTR, I'm trying to compare it to the "advertised" hp figures by Ford. When you buy a vehicle with "350" hp, you expect a vehicle that performs at that level relative to it's current boost, you don't expect a vehicle that performs at the level of a 315 hp vehicle at it's current boost except when you mash the throttle for up to 20 seconds.

Put it another way, Ford would be trying to say 315 = 350 because in a track setting you can nearly achieve that. 315 =/= 350 hp. I don't care if you can nearly permanently attain that 350 in a track setting, that doesn't mean it's going to perform like it would tuned to that level permanently. I plan to drive mine A LOT more on the street than the track and want that performance everywhere.
 

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I think we are talking apples and oranges here. You are comparing the Focus RS with 315 (guessing at this number due to some early information) hp to the Focus RS with 315 hp AND 350 hp overboost. I am comparing the Focus RS with this setup (315 hp w/ 20 sec overboost for 350 hp) vs a Focus RS with a PERMANENT 350 hp. They would be tuned differently, making it perform differently at all RPM. It would be a better accelerating vehicle at 30% throttle with a 350 hp tune than it will be with a 315 hp tune with 350 hp overboost. I'm not trying to compare it to a GTR, I'm trying to compare it to the "advertised" hp figures by Ford. When you buy a vehicle with "350" hp, you expect a vehicle that performs at that level relative to it's current boost, you don't expect a vehicle that performs at the level of a 315 hp vehicle at it's current boost except when you mash the throttle for up to 20 seconds.

Put it another way, Ford would be trying to say 315 = 350 because in a track setting you can nearly achieve that. 315 =/= 350 hp. I don't care if you can nearly permanently attain that 350 in a track setting, that doesn't mean it's going to perform like it would tuned to that level permanently. I plan to drive mine A LOT more on the street than the track and want that performance everywhere.
I don't see any problem that pushing the pedal down harder would not solve.

I can try to grab a log of target torque vs pedal position on my ST and we can see what it's actually doing.
 

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I am comparing the Focus RS with this setup (315 hp w/ 20 sec overboost for 350 hp) vs a Focus RS with a PERMANENT 350 hp. They would be tuned differently, making it perform differently at all RPM. It would be a better accelerating vehicle at 30% throttle with a 350 hp tune than it will be with a 315 hp tune with 350 hp overboost.
How are you defining permanent? Power output is constantly changing and I think you're getting hung up on the fact that the power profile doesn't have to be different when not in "overboost mode"

I'll give you an example. My old S4 was running ~23 psi spike which tapered to 21 psi. So in this boost profile I was probably putting down ~400whp. However if I unplugged my wastegate control valve max boost would be wg pressure - 14 psi. Obviously my peak power was much lower than 400, however the driving profile from vac-14 psi was the same. It was simply a matter of when the wastegates opened to limit boost.
 

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I don't see any problem that pushing the pedal down harder would not solve.
Hah, discussion over.


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overboost now 20sec long and instantly resettable

As others have said, I think it's more "opening the wastegate after 20 seconds to protect the engine" and less "overboost"


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Hah, discussion over.
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Accelerator Pedal Position vs. Target Wheel Torque. This is in 3rd gear also. Some people say "overboost" only happens in gear 3 and up.

Focus ST Torque and Accelerator Pedal.png

In words, don't worry the car will act like a 350 ft/lb(or HP) car until 20s of WOT when it detunes itself.
 

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I think we are talking apples and oranges here. You are comparing the Focus RS with 315 (guessing at this number due to some early information) hp to the Focus RS with 315 hp AND 350 hp overboost. I am comparing the Focus RS with this setup (315 hp w/ 20 sec overboost for 350 hp) vs a Focus RS with a PERMANENT 350 hp. They would be tuned differently, making it perform differently at all RPM. It would be a better accelerating vehicle at 30% throttle with a 350 hp tune than it will be with a 315 hp tune with 350 hp overboost. I'm not trying to compare it to a GTR, I'm trying to compare it to the "advertised" hp figures by Ford. When you buy a vehicle with "350" hp, you expect a vehicle that performs at that level relative to it's current boost, you don't expect a vehicle that performs at the level of a 315 hp vehicle at it's current boost except when you mash the throttle for up to 20 seconds.

Put it another way, Ford would be trying to say 315 = 350 because in a track setting you can nearly achieve that. 315 =/= 350 hp. I don't care if you can nearly permanently attain that 350 in a track setting, that doesn't mean it's going to perform like it would tuned to that level permanently. I plan to drive mine A LOT more on the street than the track and want that performance everywhere.
It's just a different peak boost level. It would make the same power at 10PSI as a 315HP Focus or a 350HP Focus since the difference is boost levels. My point is that you are disappointed that it won't always allow 23.2PSI of max boost and you are thinking that means it'll make less at 10PSI than it did if they always allowed 23.2PSI max. That's simply not the case.

Edit: And yes, I get that if different components were used to make 350HP at a non-"overboost" setting it would make a little more power elsewhere, however at low boost levels at partial throttle you wouldn't notice that very slight difference anyways.
 
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