STi Boost
1 - 20 of 20 Posts
Joined
·
33 Posts
It wouldn't worry me. The Evo motor is incredibly strong. It has proven to be much easier to tune than the WRX. I have seen some completely insane Evo's in the Uk when I have been over there. The Evo also has a truly bulletproof drivetrain something Subaru need to make sure the Sti has.
Joined
·
541 Posts
Our STi will be running less boost than the 2.0, guaranteed. Think about this: If the 2.5 was running at the same specific output as the 2.0, we'd be getting 345 hp stock. That's good news for tuners. This engine is nowhere near its potential.
I wouldn't worry about 19 psi on the Evo. Like Limeydriver said, it's very strong, and can take big boost. No one was ever worried about the JDM Evo, right? And that's a 2.0 making even more power than here, albeit on better gas. I tell you, it's those cast iron blocks. That's why I think the SRT-4 will be a major boost junkie. Watch out for big power Neons in the near future.
I wouldn't worry about 19 psi on the Evo. Like Limeydriver said, it's very strong, and can take big boost. No one was ever worried about the JDM Evo, right? And that's a 2.0 making even more power than here, albeit on better gas. I tell you, it's those cast iron blocks. That's why I think the SRT-4 will be a major boost junkie. Watch out for big power Neons in the near future.
I'm not worried about it being able to handle it, just more boost = more lag, etc.
The Neon will always be a Neon though, and its front wheel drive. Yuk. I still feel there something to be said for the classyness or "character" of a car, and the Neon falls short in that area IMO.
The Neon will always be a Neon though, and its front wheel drive. Yuk. I still feel there something to be said for the classyness or "character" of a car, and the Neon falls short in that area IMO.
Joined
·
33 Posts
Lag is really more of a factor of the turbo size than the amount of boost. Historically the Evo has had less turbo lag than the Sti.
Joined
·
541 Posts
Yes, and remember that boost is simply positive pressure in the intake manifold, right? You can't have boost at all without the turbo already spinning. If your gauge hits 19 psi, the turbo is already on full boil, which means no lag by definition.Limeydriver said:
Thus more boost does not equal more lag.
It was said on this page that the Evo's have "bulletproof drivetrains". I am of the opinion that the Evo drivetrains are very weak. We have been working on Evo trannys for the last two years and there is a mechanical quality issue. The Subaru STi drivetrains are incredibly strong. One must be careful with their choice of clutch however. They tend to favour organic clutches.
Right on.Limeydriver said:
More boost usually requires a bigger turbo, which equates to more lag. You could say then, most likely more boost is more lag. Mitsubishi's turbo technology has done a good job of countering this with titanium turbine blades and other goodies. Why do you think twin-turbo applications are potent? The smaller one spools up almost instantly (less lag) for a good torque punch but cannot produce as much high end power, the larger one kicks in for the high end.
Chobos, I'm not sure what you mean about the turbo already spinning=no lag by definition. The lag is the time while you're waiting on the turbine to spool up. The boost is generated by the turbine inside your turbo spinning. The turbo spooling up gives you the compressed air.
More power with less boost is a good thing. Could be that huge bag of crack I smoked this morning talking though...
Better get some wheel locks guys!
I don't know how much boost the STi runs and I could not get an answer from the people working the display.
Educated guess? With the RS-T's that I know of that run this kind of power, I would guess anywhere from 10-14 pounds of boost.
20+ should be no problem with this engine as long as you use the right fuel and maybe some fuel management. :evil: :lol:
At 20 pounds, I would guess 400HP would be VERY reachable.
JJ
I don't know how much boost the STi runs and I could not get an answer from the people working the display.
Educated guess? With the RS-T's that I know of that run this kind of power, I would guess anywhere from 10-14 pounds of boost.
20+ should be no problem with this engine as long as you use the right fuel and maybe some fuel management. :evil: :lol:
At 20 pounds, I would guess 400HP would be VERY reachable. JJ
Joined
·
541 Posts
That was exactly my point. If you're at 19 psi, that means the turbo is already spooled up; no waiting.D$ said:
I'm just saying that increasing the max. boost with a given turbocharger will have no effect on responsiveness. How would turning up the boost on the stock turbo give you more lag? Obviously if you go with a bigger one, lag will increase; no argument there. The issue is the more boost = more lag statement.
Let's say you have an Evo VIII, and you use a boost controller to raise max. boost from 19 psi to 22 psi with the stock turbo. This by itself will not give you more lag. The spool-up characteristics of the turbo do not suddenly change; you're only telling the wastegate not to vent at 19 psi anymore.
Joined
·
33 Posts
The sti trans we will be getting is brand new and a complete unknown. The WRX trans has major issues. The Evo has had a much better reputation, not perfect I agree, but much stronger than the WRX.
Joined
·
541 Posts
The "new" 6-speed has been around for 2 or 3 years already. It's only new to the US market. And the tuning community already knows that its strength far surpasses the WRX 5-speed. And it's used extensively in SCCA ProRally.Limeydriver said:
Not to mention that it holds up to a factory output of 320 ps in the S202.
Not exactly a "complete unknown"...
Watching someone else take the blame.
I am speaking of the STi's we have in Trinidad. We've had these cars here for the last few years. This is my opinion and the general consensus here. The STi trannys are much stronger than Evo's from the experience we've had here. The WRX is a fantastic automobile, but it's nothing like an STi and you'd only know that if you've driven both. I'm sure that the new STi's will have an improved/different gearbox. It's really difficult to imagine though because I don't see how they can improve on the present one. I think it's a perfect match. Blistering acceleration with a top speed of over 162mph. It could have done more. I don't know of any Evo's that even get to 150mph. I've heard of so many Evo trannys with transfer cases cracking under torque and other problems. I sold my Evo 4 (which had the Evo 5 engine & tranny) last year partially because of the tranny problems. In Trinidad, we love both these cars, but the Subaru's are definitely of a higher standard. Now check out www.trinituner.com and have a look at what we've got here. Enjoy!
I am speaking of the STi's we have in Trinidad. We've had these cars here for the last few years. This is my opinion and the general consensus here. The STi trannys are much stronger than Evo's from the experience we've had here. The WRX is a fantastic automobile, but it's nothing like an STi and you'd only know that if you've driven both. I'm sure that the new STi's will have an improved/different gearbox. It's really difficult to imagine though because I don't see how they can improve on the present one. I think it's a perfect match. Blistering acceleration with a top speed of over 162mph. It could have done more. I don't know of any Evo's that even get to 150mph. I've heard of so many Evo trannys with transfer cases cracking under torque and other problems. I sold my Evo 4 (which had the Evo 5 engine & tranny) last year partially because of the tranny problems. In Trinidad, we love both these cars, but the Subaru's are definitely of a higher standard. Now check out www.trinituner.com and have a look at what we've got here. Enjoy!
Joined
·
33 Posts
Dazed and Confused
Had a Legacy Twin Cam, WRX and Sti never broke a trans killed clutches in the Twin Cam and WRX, did that to my Integrale as well.
Don't mean to nitpick but new ABS driven DCCD design, new diff, new ratios, new linkages, first true volume 6 speed version. Maybe not a complete unknown but plenty to break. Remember only the US had major problems with the 5 speed. It caught Subaru off guard as they had not seen the level of failures they have seen in the US. Hope that trans cooler holds up. I think the failures might be temperature related. Not too many places in Europe or Japan that run over 100 for weeks on end.
Had a Legacy Twin Cam, WRX and Sti never broke a trans killed clutches in the Twin Cam and WRX, did that to my Integrale as well.
1 - 20 of 20 Posts
