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How much power can 2.25" exhaust support?

jmrtsus

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#21
IF there is one single area of the aftermarket where we have too many great choices for this car, it is cat back exhaust systems. [wink]
I agree, many different needs, I want a nice sound to compliment the performance, others want all out performance.........choices,choices!
 


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flagstaff
#22
Anyone try the mishimoto resonated cb? It sounds pretty tame on they're video, but videos suck at times. Something half as loud as the cpe Nexus would be great.
 


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#23
i dont see anyone mentioning that the direct injection ecoboost runs higher AFRs than old school engines producing a lot less exhaust gas than traditional injection engines so not needing as large a diameter exhaust.
 


re-rx7

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#24
i dont see anyone mentioning that the direct injection ecoboost runs higher AFRs than old school engines producing a lot less exhaust gas than traditional injection engines so not needing as large a diameter exhaust.
Exactly
 


M-Sport fan

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#25
i dont see anyone mentioning that the direct injection ecoboost runs higher AFRs than old school engines producing a lot less exhaust gas than traditional injection engines so not needing as large a diameter exhaust.
Given that factor, does it also hurt (even small) turbo spool as well? [???:)]
 


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#26
Dont think so as thats where the manifold sience comes into play. Its the reason the standard log manifold is small diameter to speed the gas flow up into the turbo. Same reason a lot of the so called bigger quick spool manifolds actualy dont work. On my efr twinscroll manifold we went up a diameter size with the same design and lost 400 rpm of spool but gained power up near red line .
 


Quisp

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#27
i dont see anyone mentioning that the direct injection ecoboost runs higher AFRs than old school engines producing a lot less exhaust gas than traditional injection engines so not needing as large a diameter exhaust.
How would AFR affect the amount of air and lbs/ hr of fuel needed to make x amount of horsepower?
 


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#29
How would AFR affect the amount of air and lbs/ hr of fuel needed to make x amount of horsepower?
i am no expert in this, i assume with the direct injection it is much more precise atomised fuel which gets full burn at a leaner mixture than electronic injection which produces less gasses. this is the reason we dont get pops and bangs unless its added by mapping it in or running methanol
 


AzNightmare

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#30
imo, unless you're changing your turbo. Size doesn't matter, get what you enjoy hearing.
Hybrid or big turbo, get 3"?.
 


Quisp

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#31
i am no expert in this, i assume with the direct injection it is much more precise atomised fuel which gets full burn at a leaner mixture than electronic injection which produces less gasses. this is the reason we dont get pops and bangs unless its added by mapping it in or running methanol
So your afr's are what at full throttle? Physics doesn't go out the window with D.I . it takes x amount of fuel to make x amount of horsepower.
 


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#32
not true a leaner burn makes more HP with less fuel at the expense of higher temperatures. DI is far more accurate and can get closer to the optimal burn without the fear or running lean and melting pistons
 


OP
B

Based

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Nope
Thread Starter #33
imo, unless you're changing your turbo. Size doesn't matter, get what you enjoy hearing.
Hybrid or big turbo, get 3"?.
I ordered the Borla a while ago. It made it to my house maybe 2 weeks ago. Weather's been stupid lately so I haven't put it on yet but I'm putting it on this weekend and changing my oil. I plan to get an x47 by the end of this year too. Hopefully the 2.25" exhaust doesn't hinder the performance THAT much. I just can't stand the sound of the bigger exhausts. They sound too burbly like there underwater about to bog down.

I also just ordered a Depo racing intercooler ;). Imma be fast now


Sent from my iPhone using Tapatalk
 


shouldbeasy

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#34
I ordered the Borla a while ago. It made it to my house maybe 2 weeks ago. Weather's been stupid lately so I haven't put it on yet but I'm putting it on this weekend and changing my oil. I plan to get an x47 by the end of this year too. Hopefully the 2.25" exhaust doesn't hinder the performance THAT much. I just can't stand the sound of the bigger exhausts. They sound too burbly like there underwater about to bog down.

I also just ordered a Depo racing intercooler ;). Imma be fast now


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Ur ma twin.

Good fuckin' yard.
 


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Detroit
#35
I ordered the Borla a while ago. It made it to my house maybe 2 weeks ago. Weather's been stupid lately so I haven't put it on yet but I'm putting it on this weekend and changing my oil. I plan to get an x47 by the end of this year too. Hopefully the 2.25" exhaust doesn't hinder the performance THAT much. I just can't stand the sound of the bigger exhausts. They sound too burbly like there underwater about to bog down.

I also just ordered a Depo racing intercooler ;). Imma be fast now


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I've had Borla on every vehicle since the first one I put it on, I love them.
The only reason I didn't on this car was the diameter but, I see hybrid turbo
dyno's going from stock exhausts to 2.5" and gaining nothing. That made me
kind of regret not buying it because I'm only going with a hybrid turbo.

On my first gen Focus I got comments all the time with my borla, people would stop
me at gas stations import and domestic people it was weird. One old dude
said he had flashbacks of his MG lol. The funny thing is that system was to BIG
for the N/A motor but, I got it because I was running nitrous and it worked out
very well.
 


J2FoRS

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#36
I ordered the Borla a while ago. It made it to my house maybe 2 weeks ago. Weather's been stupid lately so I haven't put it on yet but I'm putting it on this weekend and changing my oil. I plan to get an x47 by the end of this year too. Hopefully the 2.25" exhaust doesn't hinder the performance THAT much. I just can't stand the sound of the bigger exhausts. They sound too burbly like there underwater about to bog down.

I also just ordered a Depo racing intercooler ;). Imma be fast now


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Did ya get it installed? Impressions? Drone? Sound? Video?
 


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West Barnstable
#37
So it's a couple of years down the road and I am in the same predicament. I am curious as to how you made out with your Borla. I have narrowed down my choices to MAP, Borla and Mountune catbacks. All three are somewhat similar but different diameter pipes. I am ultimately aiming for the Pumaspeed X47 and want appropriate hardware in place as well.
 


Quisp

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#38
I have an X47R with a Mountune downpipe and stock exhaust. I prefer to go unnoticed while breaking the law .
 




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