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Is it safer to get an intake, like the mishimoto performance, without a tune or the intake with a tune. It states that you can do either, but which ones the safer bet. I dont want to have crazy problems with the car any time soon.
In an unrelated note, i love this forum. I have so many questions on a daily basis. Now i have a place to ask them all , other than google.
 

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Any aftermarket intake will need a tune.
This is very important. Mishimoto has made some nearly nefarious claims and here's the short answer:

It might be possible to run an intake without remapping the ECU, but from an engineering standpoint, the methodology is very questionable. Let me provide some quick education as to why there are gains to be had with an aftermarket intake and no tune. The common fallacy is that horsepower increases because there is less intake restriction (reduced pumping losses) or the intake charge is cooler (in the case of a Cold Air Intake -- CAI). While these claims are not inaccurate, they are only a small portion of the reason a car makes power with an intake (and no tune).

From the factory, most cars are tuned to run rich under load. This rich mixture is more knock-resistant and reduces NOx production. The optimum charge mixture to produce power is approx. 13:1, but this is far too lean for a turbocharged car (turbo'd cars are typically knock-limited). Most of the gains in a "Stage 1" tune are had by leaning the steady-state mixture under load. The aftermarket has less concern for NOx emissions or bad gas/extreme climates, so it's generally seen as OK to lean out the mixture somewhat. The caveat is that these maps MUST be run in standard climate/elevations and with high-octane fuel. In addition, some safety margin is built-in for cars with slightly different MAF and intake flow characteristics -- remember, the OEM map is meant for all cars on the production line!

So Mishimoto designs their intake to "trick" the MAFv calibration so that the engine is actually consuming more air than the ECU believes. This is typically done by placing the MAF sensor at a slightly different location within the induction tube. You might remember this trick from Quirt Crawford several years back: Crawford Eco Block? A MAF spacer? What is this? - NASIOC -- he was ridiculed quite a bit for this. IMO, this is very dangerous because it means that all load calculations (which are done by calculating air intake demand) will be incorrect. All compensations based on load will be shifted by some undefined delta. What you'll likely find is the following:

1. Mishimoto intake (no ECU remapping) produces similar power to the Stage 1 map minus the intake
2. Stage 1 + intake will produce slightly more power over Stage 1 (no intake), but with far less gains than Mishimoto claims

You make the decision here, but know that most knowledgeable people do not buy into Mishimoto's strategy.
 

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Well you have 1 option. Install the intake and tune because anything less can skew maf readings and lead to engine damage.

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A proper tune for any intake is safer without a doubt.
 

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Burko22 said:
how much more will the tune + intake get you over just tune?
A working car, in the event the MAF scaling is off enough (where a lean condition causes the motor to blow).

If you can't afford a calibration to go with the intake, you can't afford the intake.
 

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you may have misread my comment I asked is there much difference in hp/tq gains from intake + tune over stock with just tune...
 

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you may have misread my comment I asked is there much difference in hp/tq gains from intake + tune over stock with just tune...
You will want to consult your tuner.

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With a Cobb Access Port and CAI/Short Ram you should be around 250hp (at the best) at the wheels. Cobb has dyno sheets showing the percentage increase somewhere, I just can't find it ATM.
 

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As zax linked. Cobb's map notes should cover all approximate gains. However you also need to read those map notes to ensure that you are using equipment supported by the ots map.

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With a Cobb Access Port and CAI/Short Ram you should be around 250hp (at the best) at the wheels. Cobb has dyno sheets showing the percentage increase somewhere, I just can't find it ATM.
Not true. COBB says there are not enough real HP or TQ gains in order claim them. They tested their product against "many" brands they said. See attached screen shot. This comes from their own page regarding 2015- 2019 WRX vehicles.
 

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So if i'm reading that right, cobb basically said there's no difference in gains with an intake or stock once an access port is installed
 

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You are reading that the intake without a tune leans out the afr until the engine knocks at which point it retards timing robbing you of power and risks damaging your engine.
 

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You are reading that the intake without a tune leans out the afr until the engine knocks at which point it retards timing robbing you of power and risks damaging your engine.
Thanks man, only picked up a WRX last thursday so this platform is very new to me,

Cheers
 

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This is very important. Mishimoto has made some nearly nefarious claims and here's the short answer:

It might be possible to run an intake without remapping the ECU, but from an engineering standpoint, the methodology is very questionable. Let me provide some quick education as to why there are gains to be had with an aftermarket intake and no tune. The common fallacy is that horsepower increases because there is less intake restriction (reduced pumping losses) or the intake charge is cooler (in the case of a Cold Air Intake -- CAI). While these claims are not inaccurate, they are only a small portion of the reason a car makes power with an intake (and no tune).

From the factory, most cars are tuned to run rich under load. This rich mixture is more knock-resistant and reduces NOx production. The optimum charge mixture to produce power is approx. 13:1, but this is far too lean for a turbocharged car (turbo'd cars are typically knock-limited). Most of the gains in a "Stage 1" tune are had by leaning the steady-state mixture under load. The aftermarket has less concern for NOx emissions or bad gas/extreme climates, so it's generally seen as OK to lean out the mixture somewhat. The caveat is that these maps MUST be run in standard climate/elevations and with high-octane fuel. In addition, some safety margin is built-in for cars with slightly different MAF and intake flow characteristics -- remember, the OEM map is meant for all cars on the production line!

So Mishimoto designs their intake to "trick" the MAFv calibration so that the engine is actually consuming more air than the ECU believes. This is typically done by placing the MAF sensor at a slightly different location within the induction tube. You might remember this trick from Quirt Crawford several years back: Crawford Eco Block? A MAF spacer? What is this? - NASIOC -- he was ridiculed quite a bit for this. IMO, this is very dangerous because it means that all load calculations (which are done by calculating air intake demand) will be incorrect. All compensations based on load will be shifted by some undefined delta. What you'll likely find is the following:

1. Mishimoto intake (no ECU remapping) produces similar power to the Stage 1 map minus the intake
2. Stage 1 + intake will produce slightly more power over Stage 1 (no intake), but with far less gains than Mishimoto claims

You make the decision here, but know that most knowledgeable people do not buy into Mishimoto's strategy.
Reread this. It will tell you everything you need to know. Cobb has since determined that the OEM VA intake is not restrictive and aftermarket intakes offer little gain over OEM at stage 1 power levels.
 
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