Other Cars Without Turbos

[teikyo30]

I love my car, and it's stock right now, and, honestly, might just stay stock, but something has been bugging me for a while. A car like a WRX is, from what little I get about cars, just a turbo charged version of a 4 cylinder Impreza. Right? Most of the cars people compare the WRX to, BMWs, Mustangs, Infinitis, VWs, etc, all have non-turbo/supercharged engines.

My questions is how are these other companies able to get so much bang out of their engines without the use of a turbo or supercharger, and cars like mine would be neutered without it?

One of the cars I love is the G37X, and another would be the new Camaro (about the only American car I would buy). Imagine those cars with turbos. They're already pretty fast.

I know the WRX costs a lot less, so I guess a better comparison is the STi to those two cars I mentioned. The STi would still be neutered without the turbo. The Infiniti and Chevy would smoke it. Can't Subaru make an engine that performs as well without the use of a turbo?

[T0rque]

well the main reason the wrx or the sti would be slow without the turbo is the fact that they run a low compression. another reason is the low displacement.

The other companies need to use a higher displacement to gain the torque of the turbo and they need the higher compression to gain the horsepower.

[teikyo30]

I'm just trying to figure out if there's more bang for the buck in a car that doesn't rely on the turbo to perform well. My nightmare with this car is the turbo dies, then I'm stuck with a crappy 4 cylinder car that does 60 in ten seconds until I can buy a new turbo.

[T0rque]

if your turbo dies your stuck with a 3000 lbs paper weight til you replace the turbo.

Do not drive your car with a blown turbo.

[teikyo30]

if your turbo dies your stuck with a 3000 lbs paper weight til you replace the turbo.

Do not drive your car with a blown turbo.

This is why I love forums. I'm a computer guy, not a car guy. My limit with cars mechanically is changing the oil, filters, headlights, things like that. Not engine stuff. lol. So why can't it drive without the turbo? Mine's fine, I'm just curious.

[T0rque]

most of the time when the turbo goes it has small metal particles that could possibly get forced thru the motor.

[Anub1s]

Echoing what's been said in here, the reason why N/A (Naturally Aspirated, or non forced induction) cars are either as fast or faster than the WRX is:
1) Higher Compression Ratios, more compression = more bang from gas and air = more power.
2) Higher displacement and more cylinders. More cylinders = more explosions per revolution = more power.
3) Tuning. Typically they run more lean than a turbo charged engine, more air in the fuel mix = more powerful explosion = more power.
4) Valves, head design, exhaust/intake manifold design etc... The leftover stuff can all be fine tuned to get more power out of the motor. Where as with a turbo charged car, to get anything out of it you have to tune for it, N/A engines simply perform better with just better airflow. Tuning still helps of course, but it's not as necessary.

With turbocharged or supercharged applications, everything is calculated, fine tuned, recalculated and executed to the "T". You HAVE to be able to tune it correctly, otherwise you'll either get crappy power, or you'll get too much power and blow the motor. When you're forcing more air into the engine it changes things. Heat is created by both methods which requires more fuel and an intercooler to keep the charge temperatures down. Too much heat = detonation = blown motor. Less heat = more air per cycle = more power IF tuned for. Turbocharging is an exact science, more so than you're average N/A engine. Though these days, N/A engines are getting pretty elaborate and are pushing the edges of the possible more and more, so they are getting more and more fidgety. Honda has done some godly work with their K-series engines. Pushing greater than 100hp per liter out of an N/A 4 banger is quite the feat.

Anyways, I'm going to stop typing now or I'll keep going on, and on, and on.

[RayfieldsWRX]

There are many sides to this coin..it all comes down to personal preference. Bo and Anub1s covered it pretty well; another thing to consider is the AWD system on our cars. We lose a good bit of power due to having to push 4 wheels around; power that would be available for quicker acceleration from a roll if we were using 2WD. This is one of the reasons why an average V6 sedan like an Altima or Accord is nearly as fast (in some cases faster) than a WRX when accelerating from 30mph to 70mph.

I owned a G35c for a while...great car, and a great engine, but I had gotten used to a forced-induction powerband, and the V6 bored me pretty quickly.

[teikyo30]

I owned a G35c for a while...great car, and a great engine, but I had gotten used to a forced-induction powerband, and the V6 bored me pretty quickly.

Some of those cars, like the G37x are awd and still just as fast. I'm just trying to understand the car, that's all. So if turbos are so finicky, does that mean if I get the Cobb AP mapping it myself is a bad idea?

[suba-roo]

hey man,

dont worry about blowing your turbo. its not gonna happen unless you bought a lemon or someting is seriously wrong with your car. im having a blast with my stock turbo. it all depends on how you drive.. if you beat on your car, i would worry more about the transmission. theres modifications you can do that will give you nice performance without worrying too much about blowing **** up like an exhaust or an intake. i got my car bone stock and 1 year ago with 45,xxx miles on it. since then ive done a full exhaust (headers, sti uppipe, perrin downpipe, custom catback, greddy tic muffler.) , cold air intake, ive dropped it almost 3 inches, running cobb stage 2, custom ground kit.. other then that, just little things. my car pulls hard, probably not compared to some of these guys on here but its fast enough for me. the only problem ive had so far is that my clutch is starting to go. understand i beat on my car everyday.... EVERY DAY! to the floor countless times a day. stock clutch starts to go after a while but my turbo is running strong. anyway, im just trying to ease your worrys, dont be too freaked about something happening to your whip dude. its all good, and if you were to ever blow your turbo, send me a pm because i can def help you out for cheap. if i wasnt so nervous about blowing my trans, the fp green and fmic and new injectors and fuel pump and gift card for a free tune would all be in my 05 right now. haha good luck. symmetrical awd ftw.

[Anub1s]

Some of those cars, like the G37x are awd and still just as fast. I'm just trying to understand the car, that's all. So if turbos are so finicky, does that mean if I get the Cobb AP mapping it myself is a bad idea?

If you do it wrong, yeah it's a bad idea. There's a lot that goes into tuning, I've been studying it and working on my own car for a few months now and I'm STILL learning all kinda of new things.

You can't just change things up willy nilly like in the tune and expect it to just work with it. The car itself is what's finicky, not so much the turbo. There's a lot that goes into turbocharging dynamics and air flow, as well as conditions that you need to tune fuel and timing for, so it's a good idea to get a very good understanding of how turbocharging works and what's needed for tuning before making ANY changes.

[teikyo30]

If you do it wrong, yeah it's a bad idea. There's a lot that goes into tuning, I've been studying it and working on my own car for a few months now and I'm STILL learning all kinda of new things.

You can't just change things up willy nilly like in the tune and expect it to just work with it. The car itself is what's finicky, not so much the turbo. There's a lot that goes into turbocharging dynamics and air flow, as well as conditions that you need to tune fuel and timing for, so it's a good idea to get a very good understanding of how turbocharging works and what's needed for tuning before making ANY changes.

So at that point it would probably be wiser to go to one of the pro-tuners in the area and have them do it, right?

[Anub1s]

So at that point it would probably be wiser to go to one of the pro-tuners in the area and have them do it, right?

To be on the safe side, absolutely. If you want to invest this kind of time into learning how to tune, then good on ya, but if it's not something you're planning on doing as a hobby, I wouldn't bother and just let someone else do the tuning. But in the future, if you do end up doing a lot of mods, be sure to talk to your tuner about them. If you speak with one about your goals they can help you get there and can help you make the decisions you need on parts and things like that. They'll help you not waste money. :P

[teikyo30]

To be on the safe side, absolutely. If you want to invest this kind of time into learning how to tune, then good on ya, but if it's not something you're planning on doing as a hobby, I wouldn't bother and just let someone else do the tuning. But in the future, if you do end up doing a lot of mods, be sure to talk to your tuner about them. If you speak with one about your goals they can help you get there and can help you make the decisions you need on parts and things like that. They'll help you not waste money. :P

Yeah, my goal is driving, not tuning. I know it sounds retarded, but I'm 37. Kinda feel like I missed that boat. I hung out with the gear heads in high school, but all my parents got me at 16 was a BMX

Anyway, I stuck with computers. Those make total sense to me. I design computers for fun, design websites, and unfortunately deliver pizza at the moment, but I get like $25 an hour (with tips) so it isn't that bad.

[gastoys]

The WRX is a 2.5 liter 4 cylinder and you're comparing it to 3.7 liter V6 engines and 4.0, 4.6, and 6.2 liter V8 engines? It was not long ago that 6 cylinders could not push 265hp without turbos.

The 2.5 boxer is a phenominal engine making great power. Even stock with no turbos the engine produces 170hp. That's pretty good. Take 2.5 and double it to equal 5.0, now double the hp too - 340hp. So if the WRX had a 5.0 flat 8 it would be producing 340 hp, still not bad. If the WRX had a 6.2 liter flat 8 which is the same displacement as the Camaro it would produce 425hp. So IMO the WRX is right up there with V8's in power to displacement.

If the WRX had a 3.7 liter flat 6 which is the same displacement as the G37 it would produce 260hp/260tq that's not bad at all and right up there with most V6 engines.

Turbos even the playing field IMO and with 265hp/250tq for a 2.5 flat 4 that's amazing power, and with the STI its 305hp! Wow! I remember when the 3.0 V6 twin turbo 300Z was producing that same power back in the early 90s and that was for a $40k car - 15 years ago!

I would like to see Subaru put the flat 6 with a turbo in the Impreza - would probably be good for 375hp!