Stock vs Stage 1(no mods) tunes

Would anyone be willing to post their stock ROM .hex and a ROM that has been tuned for a stock car with no mods? I have a 2006 LGT. This is strictly for my own educational purposes. The tune will NOT be put on my car. I would just like to compare full tunes to see what changes are made, how they are made, and most importantly, why they are made. I have read many of the threads about tuning on lots of forums and I am to the point that I would like to see the changes in a full file format in RomRaider. I would like to begin tuning myself, but I am not willing to do anything until I have a full understanding and I think this would help. Any other advice is welcome. I am not interested in paying for an etune, I would be possibly interested in paying for someone's time to teach me how they arrived to the changes they make. The knowledge is more important to me than the immediate performance improvements. Thank you for your time and as I've stated, advice is welcome but please note that I do value the ability to tune, much greater than a tune itself.

Take a look at this thread. The stage 0 safety tunes

 

http://legacygt.com/forums/showthread.php/covertrussians-05-lgt-build-thread-218363.html

Awesome info. Thanks for the link. So the changes you displayed are safer because they make the car run richer than the stock tune, but with the avcs advance it burns more efficiently creating gas mileage and in turn better power output?

I also read your closed to open loop post. Eliminating the factory lean in boost seams like it almost be necessary for tuning to larger boost levels than stock.

oh sorry, it's not me just linking to another user who I know thought about this.

 

I know little to nothing about tuning.

Then you're at the same place I am Thanks for the link still!

Awesome info. Thanks for the link. So the changes you displayed are safer because they make the car run richer than the stock tune, but with the avcs advance it burns more efficiently creating gas mileage and in turn better power output?

 

The stock tune comes with additional timing for two of the detonation prone cylinders, which means the are even more prone to knocking. Stock tune also is very lean in boost until about 5k rpm, which is very bad.

 

AVCS tuning really helped my gas mileage in the winter months on stock downpipe. I'm now testing it with STG2 downpipe, and with summer moths, but I will say it doesn't seem to be make nearly as big of a difference on gas mileage (recently stock AVCS @0 got me 28mpg)

 

I also read your closed to open loop post. Eliminating the factory lean in boost seams like it almost be necessary for tuning to larger boost levels than stock.

 

Even at stock boost levels your AFR's need to be much richer. I haven't really tested it with Subaru, but on my 4 cyl turbo Nissan I usually step the AFR's down in this fashion:

0 psi = 12.8 AFR (Usual target NA AFR)

1-3 psi = 12.5 AFR

3-6 psi = 12.0 AFR

7-10 psi = 11.8 AFR

11+ = 11.5 AFR

 

Boxers likes a richer tune, stock tune goes down to 10.8 afr... Most people tend to tune to 11-11.1 AFR though, which is still way richer then a regular boosted 4 cylinder. Even with Boxers liking richer tunes, closed loop to open loop delay cause you to be ~14 afr until 5k rpm. Which means you are ding 14 afr at 11-13.5 psi, because by the time 5k rpm kicks around your already only pushing 8-10psi.

It sounds like I should get a WBO2 gauge and log some data on the car stock. I'd be interested to see it lean out(interested then worried) on the stock tune. I'd like to find a gauge compatible with RomRaider.

Your stock front O2 sensor is a WBO2, it's sufficient enough to see this (just not accurate bellow 11.1 afr).

 

This graph is pulled from stock WBO2. But now that you mention it I might log it against my Uego later.

http://i160.photobucket.com/albums/t188/covertrussian/Cars/05%20LGT/ECU/CL%20to%20OL%20Delay/CLtoOLDelayDynoGraphpng.jpg~original

Nevermind, stupid comment I didn't think through. So the aftermarket wbo2 will come into play when you start changing scales. Your factory readings may say your at 11.1 when you could be 10.9 or 11.0?

...closed loop to open loop delay cause you to be ~14 afr until 5k rpm. Which means you are ding 14 afr at 11-13.5 psi, because by the time 5k rpm kicks around your already only pushing 8-10psi.

 

CL/OL delay is a split second thing, and it happens based on TPS not RPM. Even still, bad news. 3krpm or 5krpm, the transition can be dangerous if you're pushing big boost in that fraction of a second.

 

Also, 5k RPM is way into the meat of the boost curve for most of the turbochargers we are putting on these cars. You can make 22psi by 3k on the stock snail, or 30psi by 5k on a GT30, so I'm not sure what you mean about only 8-10psi, unless I'm missing something.

I believe he may be talking.about the boost taper at the end of the.power band as you approach fuel cutoff. Stock peaks at like 13.5 but that's in the middle of the powerband

5krpm is right in peak boost, about 14psi even on the stock tune.

Ah. I thought the vf40 lost a lot at the top end. Am I not thinking top end enough? Haha

5k is mid-range. You won't see that kind of taper until closer to 6k.

 

Most stock-turbo Subarus are factory setup for mid-range power. Just ballparking here for a stock EJ25, that's 3500 to 5500 rpm. Low end being 2000 to 3500 and top end being 5500 to 7000. If that makes any sense

Makes sense. I'm flipping through a stage one tune on RR. Looks like 5k is right were the boost begins to taper on this tune. It goes from 16 to 12 psi between 5k and 6k

Nevermind, stupid comment I didn't think through. So the aftermarket wbo2 will come into play when you start changing scales. Your factory readings may say your at 11.1 when you could be 10.9 or 11.0?

 

Correct, it's still not as accurate as a dedicated WBO2, but good enough for a fairly stock setup.

 

CL/OL delay is a split second thing, and it happens based on TPS not RPM. Even still, bad news. 3krpm or 5krpm, the transition can be dangerous if you're pushing big boost in that fraction of a second.

 

Also, 5k RPM is way into the meat of the boost curve for most of the turbochargers we are putting on these cars. You can make 22psi by 3k on the stock snail, or 30psi by 5k on a GT30, so I'm not sure what you mean about only 8-10psi, unless I'm missing something.

 

Even if it's a split second thing, one second lean can do a lot of damage. Look at the virtual dyno graph I posted above. It was lean from 3k to 4.7k rpm during the peak boost period.

 

As for the boost numbers, its going 9psi at 5k rpm. My point was, the more boost the more fuel is needed. By the time you are getting enough fuel, you are already pushing less boost.

Looking again at the graph you posted, I see what you mean about boost dropping. I didn't see the boost line there with the AF line. Is that really typical?? I was sure my stock tune was pushing better than 9psi @ 5k RPM. In fact, it held a pretty consistent 13psi until close to 6k.

Stock tune:

 

800 0.97

2000 6.19

2400 13.54

2800 13.54

3600 13.54

4000 12.96

4800 11.99

5200 11.6

5600 11.22

6000 10.64

6400 10.25

6800 8.51

 

 

Stage 2 tune might be something like this:

800 0.97

2000 6.01

2400 12.12

2600 16.05

2800 17.64

3000 18

3200 18

3600 18

4200 17.89

5000 17.11

5800 14.41

6800 11.1

 

See how quickly it jumps off a cliff after 5K? That's not just a simple choice for tuning. It's because after about 5K the turbo loses steam and you have to dump massive amounts of WGDC into your tables to generate higher boost figures... Which means you are driving the turbo really hard, which means the turbo becomes a flamethrower. The goal isn't to just make boost; it's to make useful boost.

iNVAR thats what I thought. The Turbo is overworking, its moving air. but really hot air up at the range, meaning less molecules per area. So its actually more efficient and healthier at lower boost levels than cranking it, and the limit is varying based on what turbo you run and its capacity to move cooler air. Does anyone know where to find compressor maps for a vf40?

No compressor map for VF40 or any IHI VF turbos. I've searched far and wide. There are approximations and theories, but that's about it.

 

It is sometimes better to sharply taper off your boost and instead advance your timing. You'll make more power that way and not kill your turbo in the process. Being able to taper off boost is also why I'm personally strongly against going to a strictly only MBC setup. Hybrids are okay in my book.

I do agree with you, seeing the capabilities of the cars OEM equipment. I would also like to stay away from an MBC.

Another question, I downloaded a MY06 Base map off of OSecu for my car. I made changes to it based on the Stage 0 Safety recommendations posted by covertrussian, I like that he has dyno charts explaining his modifications as well so they seem logical. My question being, am I ok to flash that map on my ecu, or would it be much better for me to pull my own factory map and make the same changes and reflash it back on. I dont know if the ECU has an ID of some sort making it specific to a certain ROM. I wouldn't think it does since COBB AP flashes universal Stage tunes onto any car. When you marry an AP it doesn't automatically make changes to your map correct? It uses an existing map from COBBs website.

I have also disabled the CEL codes that are associated with an Invidia up pipe install which will be done before my ROM flash. I like the idea of disabling the codes rather than a resistor mod.

Pull your own map and see what its ID is first.

Awesome post @iNVAR, correct on the turbo running out of steam thus needing less boost to make usable power. It's a shame there are no compressor maps, but at the same time why bother wasting that much time with such a tiny turbo anyway .

 

+1 on pulling your map first, it's easy and takes a couple minutes to do. At that point go to Romraider Stock Rom List and find the latest compatible tune for your car (Subaru tends to make changes to the tune as they find issues).

 

Keep in mind my dyno maps are from virtual dyno, while I try to make sure as many conditions are constant, it can be very hard to have two identical runs (especially with Subaru's overzealous knock control system).

 

+1 on disabling codes vs resistor mod, if you need help on which cells to disable, check this thread out. Always better to just disable it then to hack it.