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-   -   ecu stage 1 (https://www.subaru-svx.net/forum/showthread.php?t=24136)

vwmrbill11 01-28-2005 05:22 PM

ecu stage 1
 
What in terms of horsepower and performance do you gain by adding this pkg sold on ebay for $214 and how much should installation be. Are you that have it happy with it. Bill

Earthworm 01-28-2005 05:43 PM

You don't really gain peak hp but instead improve on low end power. Check the graphs on www.ecutune.com

EddieSVX 01-28-2005 05:58 PM

Quote:

Originally posted by Earthworm
You don't really gain peak hp but instead improve on low end power. Check the graphs on www.ecutune.com
I wish I still had the URL, but I saw a dyno chart of a stock SVX once and there wasn't that big HP/torque dip they show between 2700 ~ 4000 RPM or wherever it is in the range that they claimed it dips a lot and that the replacement chip fixes.

So I dunno, I think this may improve a little but not as much as they advertise. Maybe they let go of the gas momentarily or weren't hard pressing it during those RPMs, or maybe their specific car had issues.

The HP/tq curve of the stock SVX I saw was pretty linear.

AFBeefcake 01-28-2005 06:14 PM

Well I feel more power off the line with the chip.

immortal_suby 01-29-2005 08:37 AM

I am very happy with stage 1 version 4. It made an incredible difference. The improvement is real and you feel it every day.

ensteele 01-29-2005 10:07 AM

The next question then is how hard is it to install? What does it take?

:)

longassname 01-29-2005 08:26 PM

Quote:

Originally posted by EddieSVX


I wish I still had the URL, but I saw a dyno chart of a stock SVX once and there wasn't that big HP/torque dip they show between 2700 ~ 4000 RPM or wherever it is in the range that they claimed it dips a lot and that the replacement chip fixes.

So I dunno, I think this may improve a little but not as much as they advertise. Maybe they let go of the gas momentarily or weren't hard pressing it during those RPMs, or maybe their specific car had issues.

The HP/tq curve of the stock SVX I saw was pretty linear.

Here's a plot of chiketkd's car on an awd dynojet (dynojets typically show higher #'s than dyanpacks). This is a plot of a very healthy svx with better than typicall driveline efficiency thanks to a transmission transplant. You'll notice that it comes out of the 2500 rpm stall at around 80hp. All of our runs on the factory software were about the same be them good runs or bad runs. Now we did have good runs and bad runs and the plot shown in our hp comparison is a bad run. Chike's plot would be indicative of a good run. Here let's look at it:
http://www.subaru-svx.net/photos/fil...etkd/23162.jpg

Ok, now we chose to use a bad run in our comparison. We chose this bad run not to be deceptive but to illustrate the problem with the factory tuning. The bad run is a valid indicator of real life performance because it happens in real life pretty frequently with the factory software on the us market svx. Mass air meters are great. Personally I think it's THE way to go for engine management but at the same time they like any technology do have limitations. They are slow to register the rush of air that comes in when the throttle is opened far and fast. In order to overcome this limitation there is a seperate fuel enrichment based on the throttle position sensor to stop the car from going too lean when the accelerator is floored. It uses a table to look up and add a set # of milliseconds of fuel injector pulse width according to the tps voltage. The #'s in this table are ballpark #'s since they are based on throttle position and not actual air mesaurements so in some conditions they result in the afr being a little richer than was planned and in other conditions a little leaner. Because the SVX is already nastily lean from the factory when the throttle enrichment isn't enough and the afr goes even leaner the power loss jumps from bad to terrible. I drive an SVX myself so I know about this intermittant lag all too well and I'm sure you do too. We shouldn't just pretend like there aren't times when we press the gas and the car just kind of sits there for a second before it does anything. It's an annoying problem which the stage 1 software does fix. So now let's look at the plot provided on our website:
http://www.ecutune.com/images/HPplots.gif

You should note where the plot with the stage 1 software comes out of the torque converters 2500 rpm stall. You'll never find a stock svx doing that and that's no one time thing; every stage 1 plot shows the same low end increase. Whether you are comparing to the best stock svx plot you can find or the worst you will still see that a stage 1 starts at something like 112 ( i can't remember the # off the top of my head) and stock svx's start off around 80hp.

I imagine you can appreciate the plot comparisons better now so I'll move on to touting stage1v4. The plot on our website is not of stage 1v4. It's of the original stage 1 software. Someday we'll go do some more runs and we'll post more plots. Maybe next time I show both a good and bad run on factory software so the skeptic inside doesn't get the better of anyone who would otherwise be thrilled to say goodbye to the lag in their svx. Now while we don't have any plots of v4 everyone seems pretty thrilled with it. I think it's safe to say there's a good improvement over what i think was a pretty impressive improvement with the original stage one software. We've also made some nice drivability improvements. Try to drive someone elses SVX who has it if you can.

Rotorflyr 01-29-2005 08:44 PM

I have one for my Liquid Silver, but have yet to install it.
Why you might ask?, Well the reason is simple, while I have had the car since Oct, I really haven't driven it much (ya, I know, sacrilege!) Still need to do a tranny cooler, gotta find a shop and the funds to do it, as I haven't the time, tools or inclanation (yep Im feeling kind lazy right now) to do it myself.
I'm driving my pos chevy thru the winter, and then I want to drive it a while without the chip, basicaly so I can really feel the difference! That said, from everything I've heard/read, it was well worth the money! (and then some)

immortal_suby 01-30-2005 06:55 AM

Michael hit the nail on the head.
With stage 1 the power is always there. Every time. No worrying that the motor might fall flat when you pull out in front of that truck.
It's an amazing difference.

I was becoming very jealous of the wife's turbo forester until version 4 came out. V4 is awesome. I can't wait to see the dyno plots.

Earthworm 01-31-2005 11:39 AM

Quote:

Originally posted by ensteele
The next question then is how hard is it to install? What does it take?

:)

It's easier than changing the spark plugs but requires about the same amount of patience. The hardest part is just removing/installing the ECU box.

You do learn what all resides under our dash though :)

RojoRocket 01-31-2005 01:48 PM

I've very much enjoyed the improved throttle response and muscle down low since installing the v4. With gas prices stabilized for the moment I've put off completion and testing of the 87 code option, as it's WAAAYYY too much fun the way it runs now!!

As far as difficulty, this is a job you only wish the "little woman" (literally) were of a mind to do it for you. The constant need for a third hand is always fun in such confined spaces while standing on one's head. Now, after doing it, I can see it was much easier than it appeared.

Glenn

Bigdave 01-31-2005 04:11 PM

Just thought I would add my two cents on the 87 option. I am running the V3 chip and have had it in since around September. I love it! I switched to the 87 mode when it started to snow and have run about 4 tanks of gas so far. I figured I did not need the extra power in the winter, so I would save money on gas. I really have not seen much of a difference in the preformance yet. It still runs stronger and smoother. I can't say much for the gas mileage.It always is bad in the winter though. I only get about 12-15 MPG. So it really helps to be able to put in the 87 gas. Dave.

kuoh 02-06-2005 11:32 AM

And all this time we have been blindly crushing that noise supressor thinking it was the culprit to our lag problems, when it was this poor coding all along. So does your code bump up the fuel a bit more than stock? This looks like a great mod, especially with the option to run 87 or 89 gas on a normal basis.

KuoH

Quote:

Originally posted by longassname
They are slow to register the rush of air that comes in when the throttle is opened far and fast. In order to overcome this limitation there is a seperate fuel enrichment based on the throttle position sensor to stop the car from going too lean when the accelerator is floored. It uses a table to look up and add a set # of milliseconds of fuel injector pulse width according to the tps voltage. The #'s in this table are ballpark #'s since they are based on throttle position and not actual air mesaurements so in some conditions they result in the afr being a little richer than was planned and in other conditions a little leaner. Because the SVX is already nastily lean from the factory when the throttle enrichment isn't enough and the afr goes even leaner the power loss jumps from bad to terrible. I drive an SVX myself so I know about this intermittant lag all too well and I'm sure you do too. We shouldn't just pretend like there aren't times when we press the gas and the car just kind of sits there for a second before it does anything.


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