Ford Fiesta ST Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
773 Posts
Discussion Starter · #1 ·
I come from a Subaru background so I am very familiar with Cobb. My last car was a Cobb Stage 2 2008 Subaru STI. I know that with the Subarus if you modded without tuning you could run into lean conditions and detonation issues.

Is the FiST safe to mod with say an Intake and TBE without a tune, or is a tune needed to keep the engine running within safe perimeters? Any insight would be greatly appreciated.
 

·
Registered
Joined
·
269 Posts
Modern engines are capable of keeping themselves safe. So a tune shouldn't be nessecary. But to see the full potential of intake and exhaust mods a tune is really ideal.
 

·
Registered
Joined
·
946 Posts
Modern engines are capable of keeping themselves safe. So a tune shouldn't be nessecary. But to see the full potential of intake and exhaust mods a tune is really ideal.
Eh not true in all cases..my '12 5.0 required a tune for just an intake, and its widely known with those cars that running an intake without a tune is risky. Wish that wasn't the case..but it is!
 

·
Registered
Joined
·
773 Posts
Discussion Starter · #4 ·
Eh not true in all cases..my '12 5.0 required a tune for just an intake, and its widely known with those cars that running an intake without a tune is risky. Wish that wasn't the case..but it is!
And this is exactly why I want Cobb to chime in. My STI was in the same boat as your 5.0 so I wanted to know if Cobb has any insight?
 

·
Registered
Joined
·
269 Posts
I'm not sure how actively they monitor this forum given the limited user base and the newness of the FiST. I'd give them a call and ask and then please do let us know what they say.
 

·
Vendor
Joined
·
418 Posts
Sorry for the slow response, usually I check the forum at least once a day and just missed this post! The 2002-2014 Subarus are MAF based (directly measures incoming air) and those cars are very sensitive to air intake changes which is why a tune is required when you modify the intake. However, many modern cars like the BMWs we support or the Focus ST and Fiesta ST use speed density (calculates incoming air via other sensor input) tuning logic. Therefore, you can make modifications to the car without effecting the tune. However, it is torque based tuning logic, so modifications without tuning won't make a very big impact on power since the car will by trying to meet the same torque targets even with free flowing parts installed.



Ian
 

·
Registered
Joined
·
128 Posts
...However, it is torque based tuning logic, so modifications without tuning won't make a very big impact on power since the car will by trying to meet the same torque targets even with free flowing parts installed.



Ian
Does this mean that with freer flowing parts and no tune the engine will actually be more efficient, higher gas mileage, since it's targeting the same power while not working as hard?
 

·
Registered
Joined
·
773 Posts
Discussion Starter · #8 ·
Sorry for the slow response, usually I check the forum at least once a day and just missed this post! The 2002-2014 Subarus are MAF based (directly measures incoming air) and those cars are very sensitive to air intake changes which is why a tune is required when you modify the intake. However, many modern cars like the BMWs we support or the Focus ST and Fiesta ST use speed density (calculates incoming air via other sensor input) tuning logic. Therefore, you can make modifications to the car without effecting the tune. However, it is torque based tuning logic, so modifications without tuning won't make a very big impact on power since the car will by trying to meet the same torque targets even with free flowing parts installed.

Ian

Is this likely to be an issue for tuners? Will Protuners be able to get around this or will the AccessPort be able to tune around/in conjunction with this?
 

·
Registered
Joined
·
490 Posts
Also remember the latest Fiesta's have a learning ECU. When you do a mod like an intake, it will take about 50-70 miles before you start feeling any difference.
 

·
Vendor
Joined
·
418 Posts
Does this mean that with freer flowing parts and no tune the engine will actually be more efficient, higher gas mileage, since it's targeting the same power while not working as hard?
Our Accessport mapping on the Focus ST gets better gas mileage than the stock tune ;) In general, the biggest variable in MPG will be your right foot. If your aftermarket intake makes cool noises when you smash the pedal and lift, then there's a pretty good chance you're going to smash the pedal more often, haha!

Is this likely to be an issue for tuners? Will Protuners be able to get around this or will the AccessPort be able to tune around/in conjunction with this?
Nope, won't be an issue at all! That's why we do the work we do! All of our OTS maps will take advantage of a certain modification path, and Pro Tuners will be able to make a custom map for any set of modifications once Accesstuner is released.

Ian
 

·
Vendor
Joined
·
418 Posts
Also remember the latest Fiesta's have a learning ECU. When you do a mod like an intake, it will take about 50-70 miles before you start feeling any difference.
It is important to note that the US FiST and the non-US FiST use different engine tuning logic. The US car is speed density tuning and the non-US car is MAF based. Therefore, modifications can affect the cars differently.

Ian
 

·
Registered
Joined
·
773 Posts
Discussion Starter · #13 ·
Will you be releasing tunes for your equipment at first like stage 1+SF or will you also be releasing tunes for other aftermarket intakes out there?

I know for my Subaru you also offered an AEM intake specific tune.
 

·
Vendor
Joined
·
418 Posts
Will you be releasing tunes for your equipment at first like stage 1+SF or will you also be releasing tunes for other aftermarket intakes out there?

I know for my Subaru you also offered an AEM intake specific tune.
All of our OTS maps will be optimized for our parts. But since the car is speed density based, you should be fine running other intakes with the OTS maps.

Ian
 

·
Registered
Joined
·
923 Posts
Hi Ian, do you happen to know off hand if your Plano, Texas Cobb location has the Access Ports for Fiesta STs in stock yet? My wife wants to get me one for Christmas. :eek:
 

·
Vendor
Joined
·
418 Posts
Hi Ian, do you happen to know off hand if your Plano, Texas Cobb location has the Access Ports for Fiesta STs in stock yet? My wife wants to get me one for Christmas. :eek:
I just asked them (Plano) and they said yes!

Ian
 

·
Registered
Joined
·
923 Posts
1 - 17 of 17 Posts
Top