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Discussion Starter · #1 ·
Other than if you want a noisier car that is.

The reason I ask is that none of the exhausts being made for this car give any specifics on any performance gains other than saying 'performance gain!' Well that's BS. I want to see HP and Torque specs, otherwise they're just expensive noisemakers. I'm starting to wonder if they did such a good job on the exhaust that no one has been able to come up with anything better. So far that seems to be the case for the air intake, you only get a 2 to 3 HP gain there (after spending 300+ dollars!) and you have to tune the engine to really see anything beyond that. (And I have the sneaking suspicion that you could get the same HP benefits after a tune with the stock air intake and save yourself a lot of money!)

So, back to the original question: Do any of the after market exhaust systems really gain you anything? Especially in the cat back systems. I have no interest in making my car noisier, I'd just like to go after any of the 'easy' HP gains that are out there.
 

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I don't have a specific answer for BRZ exhausts, but the easiest HP gain in most cars is obtained by installing a cold air intake. Less restriction = better airflow = more power.
 

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I don't have a specific answer for BRZ exhausts, but the easiest HP gain in most cars is obtained by installing a cold air intake. Less restriction = better airflow = more power.
Not without an ECU tune. The exhaust is choked on this car and you pick up quite a bit of power by putting a 2.5" headerback in, and you don't need a tune.
 

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Other than if you want a noisier car that is.

The reason I ask is that none of the exhausts being made for this car give any specifics on any performance gains other than saying 'performance gain!' Well that's BS. I want to see HP and Torque specs, otherwise they're just expensive noisemakers. I'm starting to wonder if they did such a good job on the exhaust that no one has been able to come up with anything better. So far that seems to be the case for the air intake, you only get a 2 to 3 HP gain there (after spending 300+ dollars!) and you have to tune the engine to really see anything beyond that. (And I have the sneaking suspicion that you could get the same HP benefits after a tune with the stock air intake and save yourself a lot of money!)

So, back to the original question: Do any of the after market exhaust systems really gain you anything? Especially in the cat back systems. I have no interest in making my car noisier, I'd just like to go after any of the 'easy' HP gains that are out there.
Perrin or Nameless IMO. Both companies have all their dyno charts to prove their products and sound good. Perrin has a blog-- PERRIN Performance Official Blog so you can read about the development, and preview new products.
 

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Discussion Starter · #6 ·
I hope you guys are right on the Perrin exhaust. Their intake doesn't really give you more than a couple of horsepower (again, without a tune, so I still mark it as questionable), but their crank pulley does free up quite a few HP and they give the number on that, so hopefully they've put up solid numbers on the exhaust.
The only reasonable excuse I can hear from a number of these places is that the car is still new and development is still in process. But they need to avoid the 'increases performance' line unless they can actually show what the increase is.
 

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Welcome to 4 cylinder natural aspirated engines.

Intakes and exhaust only add a bit of power and some response.

What did you expect out of the exhaust? 20whp? Not going to happen.

If you want top end power to increase get a cold air intake and a 3" full race exhaust. No catalytic converter. And even so you might only gain 15whp or so ontop.
 

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Discussion Starter · #8 ·
20whp? Well maybe if it's some kind of 'supercleancaliforniaARB' stuck on there stock.
But I do think it's reasonable for manufacturer's to put up the actual performance you can expect to get out of an exhaust. Because unless if drops a few pounds (7lb = 1hp after all) and gives me a reasonable amount of HP on top of that (say maybe 5 to 10?) it's just not economically feasible to go spend the $700 to $1000 dollars on one.
For a cold air intake I want to get at least 3hp out of it, and I'm not spending over 300 on it. cause again, it comes down to economics. Look at the Perrin crank pulley, that gives you an amazing return on your investment, and it's really easy to install as well. Their replacement intake tube probably doesn't do very much, but combined with a better air filter (K&N perhaps) I'd hope to maybe see a 1HP gain (And I get a reusable air-filter so it's worth the investment).

If I seriously wanted to see a large HP gain, I'd be looking at things like Nitrous, Super Chargers, or Turbo Chargers. But I didn't buy this car for that. I bought it cause it's fun to drive and it makes me smile (Hopefully not as hideously as Jeremy Clarkston does!). But if I can add some HP for a reasonable price, I will.
 

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So... Let me get this straight. You want hp per dollar but don't want to do one of the few options that will pay off. Also I'm not sure where you got 7lbs from. You need to drop 13 lbs of sprung weight to free up 1 hp in the brz. You aren't actually gaining any. Hp costs money that's the long and short of it. Just three pulls on a dyno costs about 90$ near me and to tune for an hour is 150$ that's assuming you don't need them to tune for you and you already have a ecu. I will say there are usually other benefits from modding breathing mods usually help the car rev faster and increase throttle feel. You already said you don't want a noisy car but a nice exhaust can bring a great note to almost anything.
 

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Discussion Starter · #10 ·
No, I said I will only go for cost effective options. ~$100 dollars per hp. Anything way over that isn't an option, it's a waste of money. You're better off just buying a WRX STI. because you will have spent that much more money by the time you are done.

I got the 7lbs from motorcycles, that's what we use there. figured it was the same for cars.
As for a dyno, well I have one that's free. While it isn't probably that accurate against a professional dyno, it's pretty accurate in telling me what the upgrades are doing.
As for tuning, if and when I decide to go that route I'll probably hire a pro. It's not that money is that big a deal, it's just that I don't throw money away unless I get value for it, and I'm not looking to turn this car into a huge horsepower machine.
And yes, nice exhausts can sound nice, but I don't want to listen to an annoying drone on a 4 to 8 hour trip and I sure as hell don't want a fart can on it.
 

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If you don't see the value in an exhaust don't get one. No one is making you.

Personally I like hearing an exhust. I find the stock exhaust too quiet.

BRZ/FR-S Part Proving…. All Bolt-Ons Part 1 » PERRIN Performance Official Blog

In the world of 4 cylinder naturally aspirated engines. You won't be getting much power out of bolt ons unfortunately. Should have bought an STi instead if you wanted cheap and effective power mods.

If you objective is to make the car more fun to drive. Don't look at power (its a lost cause) look into suspension and weight reduction.
 

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Discussion Starter · #12 ·
As I've mentioned before (Both here and elsewhere) I'm looking for some reasonable 'bolt on' mods that give some Hp boosts at reasonable prices. Not looking for a lot, if I could squeeze another 5 to 10 percent I'll be pretty happy. I'm not sure why so many people find that idea objectionable. Maybe I didn't present it well?

I think weight reduction in a car already this small and lite is really not worthwhile unless it's a track car. As for suspension, I suspect it's still a bit too early for the best mods to come to market.
 

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As I've mentioned before (Both here and elsewhere) I'm looking for some reasonable 'bolt on' mods that give some Hp boosts at reasonable prices. Not looking for a lot, if I could squeeze another 5 to 10 percent I'll be pretty happy. I'm not sure why so many people find that idea objectionable. Maybe I didn't present it well?

I think weight reduction in a car already this small and lite is really not worthwhile unless it's a track car. As for suspension, I suspect it's still a bit too early for the best mods to come to market.
I think front and rear sway bars will make a good difference. Get some adjustable ones and you can adjust your front/rear balance and overall roll stiffness. You can also get an easy 10whp with an ECU tune, but that isn't cheap either (but it's cheaper than an exhaust).
 

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Just put a k&n filter in the intake and be done with it. Or you can wait till the used market grows for this car. 10% boost of power is 20hp which will probably cost over a grand in new bolt ons. Which assuming you wanna stick with 300$ or less you won't get the bump you are looking for. It's not that anyone is objecting its just not feasible.
 

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One thing I've learned is that if you want to see decent power gains, you have to be ready to spend a decent amount of money. Exhausts aren't cheap, but if you get the right one, you could see an additional 2-5 hp/tq. No it's not ground breaking, nor is it cheap, but it is a good place to start a build.

Try the Perrin exhaust, and if you're feeling frisky, take a look at a Greddy intake, you'll get some easy, not major, gains. It takes a lot to get power out of some cars, so if your heart isn't into it, or you might have some regrets, just don't do it.

The only place you'd get major gains is with a bolt-on, like a turbo, but even some of those run about 7-8k and up including the engine prep for a turbo.

If you just want small, easy gains with, like you said, a 10% increase, do what suggested, look into an ECU tune, an exhaust, and an intake. Maybe wont be as much as you hope, but it'll be something.

You have to be ready to spend if you want a noticeable bump in power. I've been planning mine for a year and I already have detailed upgrade plans. Total cost? 16-20k. It's not cheap. And even with spending that much I'd be looking at maybe 150hp gain. But hey, I'm just learning a lot of this stuff, so I'm no well of information. (Feel free to correct me guys, gotta learn somehow)

Stick with what's been suggested. You'll find yourself spending probably a good 1k to get near a 10% increase. Like I said, and like others have said in the thread; intake, exhaust, ECU.

Also, not all exhausts drone/sound like fart cans. There are a lot that sound really nice; Greddy EVO3, Perrin Catback.


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Here are some of the examples of gains you can expect, this is taken from Perrin's blog.

3" Perrin intake and ECU tune vs stock


Perrin header, overpipe, front pipe, and catback exhaust vs stock


Perrin catback vs stock
 

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As I've mentioned before (Both here and elsewhere) I'm looking for some reasonable 'bolt on' mods that give some Hp boosts at reasonable prices. Not looking for a lot, if I could squeeze another 5 to 10 percent I'll be pretty happy. I'm not sure why so many people find that idea objectionable. Maybe I didn't present it well?

I think weight reduction in a car already this small and lite is really not worthwhile unless it's a track car. As for suspension, I suspect it's still a bit too early for the best mods to come to market.
Weight reduction and suspension are the best ways to make the car faster around the track. You won't get much power out of the cars 2.0L motor without engine work or boost. None of the bolt on mods are that great of a deal. They all barely give you power and they are expensive.

I don't think its too early for the best mods to come. If you are talking about value you likely wont want to afford the best suspension mods anyways. A set of race designed dampers will cost you well over $10k. You could likely spend the cars worth just on the suspension.

Id say the KW V3s are a safe buy.
 

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If you don't see the value in an exhaust don't get one. No one is making you.

Personally I like hearing an exhust. I find the stock exhaust too quiet.

BRZ/FR-S Part Proving…. All Bolt-Ons Part 1 » PERRIN Performance Official Blog

In the world of 4 cylinder naturally aspirated engines. You won't be getting much power out of bolt ons unfortunately. Should have bought an STi instead if you wanted cheap and effective power mods.

If you objective is to make the car more fun to drive. Don't look at power (its a lost cause) look into suspension and weight reduction.
STIs are not cheap to mod either. Just a little more bang for the buck initially. And adding power is never a lost cause. Weight reduction is pointless unless you drive competitively in an unmodded class. Not really something you will notice on the street. Suspension is great on and off the track and will change your driving experience drastically.

One thing I've learned is that if you want to see decent power gains, you have to be ready to spend a decent amount of money. Exhausts aren't cheap, but if you get the right one, you could see an additional 2-5 hp/tq. No it's not ground breaking, nor is it cheap, but it is a good place to start a build.

Try the Perrin exhaust, and if you're feeling frisky, take a look at a Greddy intake, you'll get some easy, not major, gains. It takes a lot to get power out of some cars, so if your heart isn't into it, or you might have some regrets, just don't do it.

The only place you'd get major gains is with a bolt-on, like a turbo, but even some of those run about 7-8k and up including the engine prep for a turbo.

If you just want small, easy gains with, like you said, a 10% increase, do what suggested, look into an ECU tune, an exhaust, and an intake. Maybe wont be as much as you hope, but it'll be something.

You have to be ready to spend if you want a noticeable bump in power. I've been planning mine for a year and I already have detailed upgrade plans. Total cost? 16-20k. It's not cheap. And even with spending that much I'd be looking at maybe 150hp gain. But hey, I'm just learning a lot of this stuff, so I'm no well of information. (Feel free to correct me guys, gotta learn somehow)

Stick with what's been suggested. You'll find yourself spending probably a good 1k to get near a 10% increase. Like I said, and like others have said in the thread; intake, exhaust, ECU.

Also, not all exhausts drone/sound like fart cans. There are a lot that sound really nice; Greddy EVO3, Perrin Catback.


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16-20k seems a little much for 150hp. We have all seen 400+ on stock engines with turbo kits. Forged pistons are already available. This car is turning out to be very tuner friendly. Its just that you have to pay to play.

To the OP this car wont yield much gain with just an intake and exhaust. But it may change the way you enjoy the ride. Sorry not trying to be an a$$ but some of your guys information is misleading.
 

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16-20k seems a little much for 150hp. We have all seen 400+ on stock engines with turbo kits. Forged pistons are already available. This car is turning out to be very tuner friendly. Its just that you have to pay to play.
I guess I should have specified, half of that is a turbo kit, and the rest of it are other body/wheel/tire/exhaust/etc. modifications. My apologies.
 

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No foul norse just dont wanna scare of some of the guys that are new to tuning.
 
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