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Subaru Impreza WRX - READ ONLY

11554 messages,  Last post on Nov 07, 2006 at 12:41 PM

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What is this discussion about? Subaru Impreza, Sedan

Messages Page 481 of 1156

#4797 of 11554 Interesting tidbit by hunter001

Jan 20, 2002 (5:48 pm)

One of the i-clubbers asked Subaru about the difference between the RS and WRX suspensions, and this was their answer:
 
----------------------------------
 
Suspension comparison between 2002 Impreza 2.5 RS and WRX.
**********************************************RS**************WRX
Stabilizer bar diameter (mm)****F:********20**************20
Stabilizer bar diameter (mm)****R:********13**************20
Travel (mm)*********Front Jounce*********100**************80
********************Rebound****************100*************110
***********************Rear Jounce*********115*************110
*************************Rebound************90**************95
Spring Rates (N/mm)******Front(MT,AT)26,27.7**********28.5
*****************************Rear(MT, AT)20.5,22.6*******20.9,23.1
 
Roll center height is the same for both models.
 
Information is taken from the Motor Vehicle Manufacturers Specifications.
I hope that this helps with your research. Best wishes!!
 
John J. Mergen
Subaru of America, Inc.
-----------------------------------
 
Interestingly, the Auto-WRX/Auto-RS have stiffer springs than their Manual counterparts. I would have assumed the opposite to be the case !!!
 
Later...AH

#4798 of 11554 hazdaz by bedabi

Jan 20, 2002 (5:53 pm)

I only have the Stromung muffler. That's it. I had a cat back, but put back the stock pipe between the last cat and muffler to reduce a little interior noise. It's 2.5" in diameter, so there's not much restriction in that pipe. In other words, it's perfectly legal. Taking out a cat is not.
     The exhaust comes in five parts: after the exhaust manifold, there is the 1) up-pipe with first cat before the turbo; 2) downpipe with second cat after the turbo; 3) front midpipe with thrid cat; 4) second mid-pipe with resonator; and finally 5) the muffler. If you're interested, e-mail me and I can send you a schematic diagram.
     As for high RPM launches, I don't think any one can really say with certainty how bad it is for our cars. But Subaru does have a reputation for its transmission being the weakest link in its reliability (think high HP SVX). After all, the WRX hasn't been here a year yet. But anyone will tell you that high RPM launches do cause more wear on a clutch. How much, I can't say.
     You can't compare it with an auto tranny, since it simply doesn't allow for high RPM launches. I think I read that 0-60 times for the auto were like 7.5 secs, and this was while standing on the brake while revving the engine!
     I usually slip into first gear at around 2000 RPMs or less. If you're stalling getting into first gear, give it a little more gas before you engage the clutch. Release it halfway for a split second until you fell it catch then release it quickly but smoothly all the way.
     You should come to one of our i-club meets in Queens sometime. It's a great way to compare and contrast different mods.

#4799 of 11554 bedabi - some points to keep in mind by mgreene1

Jan 20, 2002 (6:16 pm)

You're exhaust is probably "technically" illegal unless you have it in writing that it's emissions-certified. Still, my guess is that you shouldn't have any problems passing emissions testing if you haven't messed with the catalytic converters and if you haven't done any other mods.
 
The times you posted are what could easily be extracted from a bone stock WRX 5-speed sedan. Despite being louder and raising warranty and emissions concerns, your exhaust evidently doesn't do much to help performance. Dyno charts should be taken with a grain of salt especially when it comes to measuring small differences. The same exact car can test differently from one dyno run to another on the same day. It would be interesting to see some rolling start times from 0-60 bone stock and then bone stock with an aftermarket exhaust setup you described. If your point is valid, there should be a measurable improvement in the times. Have you seen any such testing? You'd think that SCC, being the pillar of credibility that it is, would have done this. Just provide some hard performance numbers to back up your claims and I'll gladly retract my skepticism and become a true believer.
  
Off-topic: Sorry about your speeding ticket. The last thing you want is a speeding ticket on your driving record in NY. The state insurance law allows an insurance company to increase premiums for two speeding tickets within a given timeframe regardless of points (unless that law has been changed since I've last read it). You may want to hire an attorney ($75 or so) to see if this could be changed to a no point, non-moving violation, e.g., parking on the highway. That has a fairly steep fine so the municipality gets the same (or more) revenue but you keep the moving violation off your driving record. Of course, this is my (perhaps misinformed) personal opinion, not legal advice per se.
 
hazdaz, if the aftermarket exhaust provider doesn't explicitly state it's emissions-legal *in writing* then it probably isn't. I wouldn't worry about the clutch unless you smell something awful. Starting below 2000 rpms shouldn't pose any problem unless you are riding the clutch. Occassionally, I'll use a little too much clutch at lower rpms and smell something but it's not that big of a deal and I don't sweat it. However, if you see smoke and there's a God-awful smell that doesn't go away then that's pretty bad news.

#4800 of 11554 by ateixeira

Jan 20, 2002 (8:26 pm)

AH: the stiffer spring rates are probably due to the higher curb weight of the automatic models. But you love a conspiracy theory as much as anyone, so go ahead and call the automatic sportier!
 
ASC and the shop that installed my roof offer a liftime warranty for leaks and squeeks/rattles. So I guess any structural creak would have to be audible for them to have to address it.
 
-juice

#4801 of 11554 re: launches by elec3

Jan 20, 2002 (10:30 pm)

It's generally the price you pay for driving a car with a large turbo. It has two personalities, mom's station wagon, and top fuel dragster. I played around with a silver WRX sedan one time and learned a few things. My car is an auto Mazda Protege5 which is quick if you really wring it out but simply not in the same class as a WRX when it comes to speed. With my whopping 135ft-lbs of torque and an automatic, I was able to blow the WRX off the line. Not even close. If I run my Protege up to redline I can hit 40-45 miles an hour in first gear, let off the gas, and be right in the middle of the powerband in second. I was up about a carlength or two when the WRX driver got his revs in the right spot and the turbo kicked in. At that point we were around 35 or so miles an hour and he took off like the car was shot out of a cannon. He blew way way way past me and, even though the Protege5 is usually at its quickest from 40 to 60 miles an hour, I couldn't begin to compete with the extra 100 horses his turbo was providing. Getting a quick start with a manual WRX seems to simply be a matter of finding a way to get your revs up soon enough for the turbo to do its job. Peak power and torque in this car are at comparatively high rpms and that is what you are noticing when you take off from an idle at a stoplight.
 
PS: It's very difficult to drive an automatic transmission car fast. It can certainly be done but it takes a lot of practice and a good degree of "feel" for the engine and transmission. You have to be able to feel and recognize what gear you are in and correctly guess whether stomping on the accelerator at that moment will keep you in your current gear and send you zipping forward or cause a downshift which will make your revs zoom towards the redline and you zoom...nowhere Forcing gear changes in an automatic is really more of an art than a skill, but it's a fun challenge for those times you want to get off the "all shifts at 2800rpm autopilot" feeling.

#4802 of 11554 mgreene by bedabi

Jan 21, 2002 (12:35 am)

First of all, the times I posted was in no way referring to any power gains. I only mentioned them for Hazdaz' benefit in attempting to explain how to launch. I'm no professional driver, and I doubt I could recreate launches well enough to provide an accurate "before and after" analysis.
     Second, if you read any of my prior posts, you'd realize that I not only expressed doubt that any cat-back produces additional power gains, but that I never claimed to get any power gains. What I did claim was that in my own car, I've experienced no loss of power in the low RPM range and no bogging with my replacement muffler as you've only predicted. I don't see how you can dispute my first hand experience in my own car.
   Third, SCC printed dyno results of the difference between a stock car and the Subaru N-class road racing car without catalytic converters. My point was that the simple notion of requiring any kind of backpressure for more low-end torque is dubious. And yes, acceleration times were notably better (unfortunately, I don't have the magazine handy to post them - e-mail me and I'll send them to you when I get home). If you are able to cite other published dyno or track measurements from more reliable sources other than general skepticism, I invite you to do so.
     Fourth, I AM a lawyer. I'll be going to court to work a deal. Thanks for your advice though. Being a trial attorney myself, I'll vouch that you were pretty much right on.

#4803 of 11554 Esq by paisan

Jan 21, 2002 (7:09 am)

I know the manager at your dealership personally. He wouldn't jerk you around. E-mail me off line if you want to discuss it further.
 
-mike

#4804 of 11554 juice by hunter001

Jan 21, 2002 (7:57 am)

AH: the stiffer spring rates are probably due to the higher curb weight of the automatic models. But you love a conspiracy theory as much as anyone, so go ahead and call the automatic sportier!
 
The difference in curb weight between the manual/automatic is 55lbs....not enough to justify your theory. I think there are a lot of other variables in this equation than what meets the eye. A Subaru engineer can maybe throw light on why the Autos are setup with a sportier setup than the manuals. The exact opposite of what the Lexus IS300 has done. They have higher spring rates in the manual vehicles (even though IS300 manuals are about 50lbs lighter than the IS300 Automatics, again disproving your theory). Does the better AWD/more efficient power/torque transfer characteristics in the Auto-WRX (a difference present in the Subaru cars but not in the IS300) have anything to do with this ??
 
I would never have guessed that Subaru had provided stiffer springs in the Automatics, if I had not seen these specs. Such a lot of these differences do not come up in the regular specs, does it?
 
Later...AH

#4805 of 11554 Shifter problem? by cinosweive

Jan 21, 2002 (10:48 am)

Is it me or the car?
 
I seem to have problems finding 1st and reverse about 20 to 50 percent of the time. The shifter just doesn't seem to want to go in either gear - I either have to "re-clutch" it or fish around for a bit. Once I am rolling, the shifter is great.
 
Has anyone else experienced this?

#4806 of 11554 bad sub trans by rezo00

Jan 21, 2002 (11:32 am)

Subaru and nissan auto trans are pretty crappy for accileration. Mercedes, BMW , Lexus, Acura, honda,Audi, and GM all have much faster shifting auto trans for one reason or another...though the G35 might be different...no one knows yet.

Messages Page 481 of 1156

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