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Discussion Starter · #1 ·
Just picked up a '22 WRX. Not first sports car or even race car, but first Subaru. This thing is a hoot. The engine pulls hard up to redline, and then cutoff - argh!!!

Before kids, I used to race a 1982 911SC and 1972 240z with a Rebello race motor. I learned to drive on an '82 Subaru GL wagon. Usually, when you're approaching redline, the motor stops making power and you're just revving. Not with the new WRX. This thing feels like it could pull to 7k no problem. Will be interesting to see if some of the mods coming out will allow the motor to sing to higher rpms and up the boost a little.

There is sooooo much potential for more power in this motor.
 

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Redline is a meaningless number.
 

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My new C8 has a redline of 6600 and its still an amazing car so idk. I don't think anyone buys a subaru to get porsche redline numbers.
 

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Very true. Was watching a video about the differences between the 2.0 and 2.4 motor. Sounds like the 2.4 is way overbuilt and could easily handle a little bit more.
As long as it's built the same as what's in the other vehicles it's quite a stout unit.

Although I like the sound of high rpms I don't know if you would be as happy here as you think as the engine is falling off at 5500. I guess you could push it to 7k but you'd likely be disappointed as at that point I'd guess the induction system is beyond it's effective range.

You'd also be just moving any possible power band to the right. Not gaining a longer one. So you'll have the exact same feeling but audibly it will sound faster.

I'd look to what's going on with the other fa24f engines and see if it's worth it. If I recall it's got a pretty long stroke and is over square so a higher rpm may not be the best idea.
 

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Very possible. It's just very interesting how hard it pulls to 6k then cuts off. Feels like there's way more potential.
Yeah, just about every forced induction engine does that. It's because at the end of the power and the blower is outside of it's efficiency range.
 

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Discussion Starter · #16 ·
Yeah, just about every forced induction engine does that. It's because at the end of the power and the blower is outside of it's efficiency range.
Interesting. I have only had NA vehicles in the past. This is my first turbo. With NA motors, they lose power near the redline. Didn't realize turbos don't act the same way. Thanks for the clarification.
 

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Sounds like you'd be right back in the same boat as the FA, and even the EJ to an extent. I bet it would ruin the drivability journalists are praising.
Probably not. Air flow at lower rpm won't be affected by raising redline, unless you modify the turbo. It should just lose power at higher revs before hitting cutoff.
 

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Probably not. Air flow at lower rpm won't be affected by raising redline, unless you modify the turbo. It should just lose power at higher revs before hitting cutoff.
To make use of the higher rpm without having a huge drop off where it already drops off you'd have to change the cam profile sacrificing that lower rpm grunt.

It's a trade off. It's why you don't find high rpm engines with any balls.
What I would have thought too, but this is my first turbo. It's possible I just don't know what I'm talking about :)
It's not as simple of just tuning. The dropoff in all of the dunp charts ive seen starts at 5000-5500. So if you just add more rpm you'll see the end of the curve where it just tanks.

As rpm goes up you need way more air. You are past the turbos efficiency at some point and it's lack of effectiveness is compounding that issue further.
 

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Discussion Starter · #20 ·
^^^ Great info, thanks. Interesting that charts show a dropoff around 5k to 5.5k because it still feels like it's pulling hard. Will be interesting to see what the tuners come up with.
 
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