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Hi Guys, took my FiST for it's 1st dyno run after fitting the Finsport induction kit. My gains were 15bhp and 30NM more over stock FiST that ran just before me. Very happy with the results and good bang for buck.
 

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Discussion Starter · #7 ·
Are these gains over your baseline dyno runs or based off comparing your runs the the previous car that was dyno'd just before yours ?
A FiSt that ran just before me, both similar mileage, his is bone stock, mine has the CAI. Know it' snot perfect science, but a good indication.
 

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Does anyone know whether a CAI or TBE will require a tune? Are the FiST MAP or MAF cars, or a combination of both?

I know that my Subaru required a tune with a CAI or TBE as you would run the risk of blowing an engine due to the modifications causing lean conditions in the AFR and thus causing the engine to go POP.

I know that some VW's are able to be modified without a tune, but obviously to get your maximum gains you would need a tune.

Basically I am looking for COBB to chime in here. Let us know so that we can modify intelligently!
 

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A cold air intake does not require any kind of tune, what is the difference between driving your car on a very hot summers day and a very cold winters day. The engine ECU monitors many things and one of them is inlet manifold temps.
 

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A cold air intake does not require any kind of tune, what is the difference between driving your car on a very hot summers day and a very cold winters day. The engine ECU monitors many things and one of them is inlet manifold temps.
Yes but depending on how the airflow is monitored it can throw out your fuel trims.

Regardless if you have a N/A or Forced Induction engine, if you add an intake you will gain power. If you tune for that specific intake your gains will be greater.
 

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And just to add to add to that, I have heard stories of the latter model turbo Subarus leaning out when fitted with a 3 inch turbo back exhaust.
 

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And just to add to add to that, I have heard stories of the latter model turbo Subarus leaning out when fitted with a 3 inch turbo back exhaust.
I come from a 2008 STI.

A catback exhaust you are fine but a turboback or a downpipe alone will cause lean conditions. An intake will cause lean conditions. A BOV will cause lean conditions. This is all without a tune mind you.
 

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Yes but depending on how the airflow is monitored it can throw out your fuel trims.

Regardless if you have a N/A or Forced Induction engine, if you add an intake you will gain power. If you tune for that specific intake your gains will be greater.
Disagree, ever noticed how your car goes better on a cold night compared to a hot day. The fuel and ignition maps are already there in the engine ECU to compensate for changes in ambient temps.
 

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cold air is more dense thats why u get more power. cai's for the most part are crap even with a tune. the stock st intake looks pretty good to me. also those kn oiled filters are a waste of money, :)
 

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Disagree, ever noticed how your car goes better on a cold night compared to a hot day. The fuel and ignition maps are already there in the engine ECU to compensate for changes in ambient temps.
I agree with this. We are not talking about the type of intakes. A short ram typically makes less power than a CAI. Cold air is more dense so you can cram more air and fuel into the piston creating a bigger bang. Easy...

If you have a MAF or MAP sensor in your intake will greatly alter what an aftermarket intake will do to your car. If you have a MAF sensor and throw on an aftermarket intake, your MAF sensor is giving the engine the amount of fuel that is programmed for the factory sized intake. When you change that and the engine is getting more air then it thinks, you throw your AFRs lean which then causes detonation and engines tend to explode when detonation occurs. That is why you tune to compensate for that.

MAP sensors work on air pressure and they are a little more lenient. Some cars (VW's) actually have a combination of MAF and MAP sensors.

Regardless of what you have, an intake will gain you a little bit of power typically, but tuning for it will net you the best gains. It only makes sense.
 

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I agree with this. We are not talking about the type of intakes. A short ram typically makes less power than a CAI. Cold air is more dense so you can cram more air and fuel into the piston creating a bigger bang. Easy...

If you have a MAF or MAP sensor in your intake will greatly alter what an aftermarket intake will do to your car. If you have a MAF sensor and throw on an aftermarket intake, your MAF sensor is giving the engine the amount of fuel that is programmed for the factory sized intake. When you change that and the engine is getting more air then it thinks, you throw your AFRs lean which then causes detonation and engines tend to explode when detonation occurs. That is why you tune to compensate for that.

MAP sensors work on air pressure and they are a little more lenient. Some cars (VW's) actually have a combination of MAF and MAP sensors.

Regardless of what you have, an intake will gain you a little bit of power typically, but tuning for it will net you the best gains. It only makes sense.
Depends on the design of the stock airbox... an SRI and a second cat delete on a Genpoo Mazdaspeed 3 (2010-2013) would net over 50hp gain... without a tune. With a tune, slightly less peak power BUT more power under the curve where it is more useful (plus giving full power in 1st, 2nd and 3rd gears). HOWEVER, unfortunately on *some* vehicles* the fuel pumps would start to act up and not provide the required 1600+ psi @ WOT. Interestingly enough, the CAI kits for the same car made less power... even with a tune. I never saw a dip in fuel pressure ever, but to do other mods required either changing the internals (same internals as VW GTI/Audi fuel pump) or going with a new unit altogether. The $400.00 to 1,000.00 price tag for a fuel pump (which would be needed to essentially do common bolt-ons) was a serious detriment to me wanting to spend money on that car. I hope the FiST doesn't have any issues like that, although I don't plan on doing a lot to my car other than a few bolt-ons (intake, exhaust, possibly an intercooler and of course a tune).
 
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