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Is the stock cat back and intake ok for a stage 3 level performance?

Hijinx

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#21
Assumption 3: "The car would be getting rid of more exhaust gasses than cold air that its able to take in... Definitely NOT optimal for performance. "

Answer: Again the reality is while it's not 100% optimal it still provides real world gains. The total intake/exhaust system does not have to be 100% balanced to be working better than factory with regards to flow numbers.
To add to this point: Variable Cam Timing and Direct Injection; they're magical (not really). Cobb has given calibrators a great amount of control over the cam timing and fuel injection. So, getting rid of more exhaust gasses than cold air that it's able to take in isn't quite a valid statement. We're not locked on cam timing. And thanks to DI were def not locked on the intake cam for fuel injection.


Some Guy On The Internet
 


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#22
To add to this point: Variable Cam Timing and Direct Injection; they're magical (not really). Cobb has given calibrators a great amount of control over the cam timing and fuel injection. So, getting rid of more exhaust gasses than cold air that it's able to take in isn't quite a valid statement. We're not locked on cam timing. And thanks to DI were def not locked on the intake cam for fuel injection.


Some Guy On The Internet
Exactly right. There's so much more to it than just "More air/More fuel" and the numbers show it. There is power to be gained when removing restrictive components, in this case the DP being one of them.
 


Hijinx

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#23
That seems strange... when my buddy took out his stock intake and i was looking it over, it definitely looked very restrictive... But maybe thats just me after being used to short-ram intakes on everything that ive worked on LOL. As for the exhaust, that really doesnt surprise me as the FiST is a "sport" model!
The Fiesta uses torque-based, volumetric efficiency (how "full" the cylinders are) tuning. Basically, if it doesn't increase the actual mass airflow (compared to the theoretical mass airflow) you won't see a performance increase. The intake on this car is really not much more than a filter on a long pipe...well it measures intake air temps too which would start another war if we start talking about that, so let's not lol.


Some Guy On The Internet
 


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#24
The Fiesta uses torque-based, volumetric efficiency (how "full" the cylinders are) tuning. Basically, if it doesn't increase the actual mass airflow (compared to the theoretical mass airflow) you won't see a performance increase. The intake on this car is really not much more than a filter on a long pipe...well it measures intake air temps too which would start another war if we start talking about that, so let's not lol.


Some Guy On The Internet
LOL thats good to know! Im very happy I joined here and started learning more about these cars! My buddy is really going to hate the fact that I am going to know more about his own car than him! ;)
 


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#26
I don't mean to ask the obvious, but since nobody has brought it up, why not just get a custom tune? It sounds like you had a bad experience with one tuner, but there are several other well known and reputable tuners available. I wouldn't waste my time guessing if an OTS tune will work different than intended. Get the car dialed in for what you have and have the peace of mind it's done right.
 


OP
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Thanks, Fiesta gurus! I really just wanted to confirm that all that I have read was accurate. There's just so much info out there and one can get confused.
 


M-Sport fan

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#30
I like the quiet, stealthy exhaust.
So do I, but I HATE burning up my clutch from over-revving on take off (and even during on the move shifting) because the damned factory system (and the whole car itself) is so effing QUIET that I cannot hear the engine!

So, the CP-E Nexus system I'm getting becomes/serves as a 'clutch saver'. [wink]
 


OP
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Thread Starter #31
I don't mean to ask the obvious, but since nobody has brought it up, why not just get a custom tune? It sounds like you had a bad experience with one tuner, but there are several other well known and reputable tuners available. I wouldn't waste my time guessing if an OTS tune will work different than intended. Get the car dialed in for what you have and have the peace of mind it's done right.

I didn't have a bad experience with stratified. I had him put in a feature that was a "use at your own risk" sort of deal. I was mainly asking if I was going to be at stage 3 level without catback and intake upgrades. I know that the stages really don't mean anything (they could have called them 3, 4, 5...), but wanted to know if that's the level I have reached.
 


M-Sport fan

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#32
The Fiesta is capable of putting down at least 350whp on the stock intake
Which is EXACTLY why I am keeping the factory intake, and also for the 'stealership stealth' factor, since the aftermarket intake systems most install stick out worse than a sore thumb to the service departments if one needs to go back there for warranty/TSB work.

The Mountune at least retains the top of the stock air box, but the rest is very noticeable as not factory anyway, so that defeats that point. :(
 


M-Sport fan

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#33
I didn't have a bad experience with stratified. I had him put in a feature that was a "use at your own risk" sort of deal.
The more I hear about the Pops/Crackles/Explosion feature, the less I want it, but I am STILL getting the excellent Stratified Flash Tune itself.

Hopefully, the Nexus CBE is enough of a 'noisemaker' that I will not even need the closed throttle extra shotgun blasts. ;)
 


Bluedrank

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#34
So what was the resolution with the crackle and pop tube possibly damaging the cat? Did you end up narrowing in on whether it was the cat or the sensor?

I'm curious because I'll eventually get an ap and tune from them.
 


OP
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So what was the resolution with the crackle and pop tube possibly damaging the cat? Did you end up narrowing in on whether it was the cat or the sensor?

I'm curious because I'll eventually get an ap and tune from them.
I just pulled the factory downpipe because everything I read was that the secondary o2 sensor hardly ever goes bad, and when you do swap it, the light will come back on. There was so much involved in just getting to the plug for the sensor that I said screw it, and just replaced everything. New sensors and downpipe for me so that I'm done with it in one shot.
 


M-Sport fan

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#36
^^^We still want to know IF there was any actual damage to the factory catcon (i.e.; melted, cracked, burned, chunked, or clogged honeycomb ceramic substrate) caused by the PnC tune option. [dunno]
 


OffTheWall503

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#37
I'm curious about how many BT guys are running stock intake. From what I've seen if anyone mentions running stock intake they give the stink eye.
 


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