I've got an XEDE. I LOVE MY STAGE 1! you won't regret it

 

remember josh, the xede sets timing via offsets from the oem ecu. the utec is a hard coded timing advance number. that is a major difference in the two units.

also, afaik, the xede does not offer the open loop fueling (ie. built-in maf vs rpm fuel tables) that the latest utec flash does. with OLF turned on you can set your rev limit wherever you want it--once the utec takes control past your tps crossover, it is COMPLETELY in control.

jm2c
ken
happy utec user

 

hey josh,

1st thing to keep in mind: they are ALL compromises. you have to learn what each of the solution's strengths are, and what their weaknesses are, and make your decisions accordingly.

"my question about the 'full control' of the UTEC versus offset of the XEDE is that isn't the offset method safer? Say the ECU sees some condition for which it decides for the safety of your motor that it needs to drastically pull timing (say bad gas or extreme heat or whatever). "

yes, that is exactly what will happen. but, keep in mind, even the oem knock control algorhythm is far from perfect. for example, it stops listening over 5500 rpms. in other words, knock higher than that, and you won't have ANY knock control to pull timing or enrich fuel.

the oem solution is to be rather productive and sensitive in the midrange, where it is most likely to knock in the first place. if you get a single knock event, it will record this in a table, so that timing will end up slightly retarded in that one load/rpm range and not in others.

if the knock continues to occur, especially at various other load/rpm sites, then ultimately the ecu will go into a global correction setting and pull timing globally. in this way the upper rpm ranges will be "protected" in the same way. if the global correct becomes severe enough a "high det" map is swiched in which has LOTS of fuel, minimal boost and minimal ignition advance.

what's important to note is that the oem ecu is adaptive, and "learns" where knock occurs and will "remember" that it needs to have slightly retarded timing in that region. over time, the ecu will attempt to readvance the timing, both in the individual load/rpm ranges, as well as the global adjustment. if the knock stays away, all is well, and the "flat spots" in torque commonly felt when the ecu pulls advance will decrease.

so the xede ends up setting offsets on top of the ecu's timing numbers. the problem is that you don't really know when the ecu is going to decide to start adding timing advance again--it's out of your hands. so your offsets are built on a dynamic table which is subject to change, and which you cannot rely upon as being optimal. in theory the system sounds like it would work perfectly, but the implimentation is generally found to be a bit lacking due to this day-to-day variability in timing.

people with xedes put down good power, and they seem to be doing so reliably, so take that for what it's worth.

the utec, being static, DOES require more user interaction. for example, while it reacts very quickly and effectively, it does NOT "learn" any knock prone areas and remember where they are. in a nutshell, that is YOUR job as the tuner. if the car knocks you NEED to find out why (by collecting datalogs) and address the issue yourself.

despite what some folks believe, generally, utec maps, if not tuned to that last 10% of power output, are very usable across a wide variety of load conditions (cargo mass, hills, a/c, etc) and atmospheric conditions (temp, humidity). on the other hand, i LOVE tweaking the maps and update them at least once a week. i still have not been a utec owner through all 4 seasons and i take a lot of pleasure in tracking how gas formulations, weather conditions, and various mods change the parameters of how the car runs. in that respect, either the xede or utec will provide a LOT of enjoyment and will teach you volumes about how your car runs, and what it means to have a well-tuned engine.

i'd write more but i must run... fire away with more ?s if you'd like and i will return to this thread.

ken

 

yes, you're right there. the utec and xede both "know" what the stock ecu is "doing," since they are intercepting the signals to and from it. but you are also correct in thinking that they are not as complicated as the oem ecu. they both demand more attention to make sure things are operating properly. in fact, most of the "issues" in the utec tuning world are around the very tricky handoff or transition region, where the control of fuel/boost/timing switches from ecu to utec and/or vice versa. i am hoping that the next version of utec software will take steps to make it easier (ie some data interpolation), but who knows how it will turn out?

otoh, i'll give you a real-life example... a week ago, i got a free fill up at a local mobil gas station. now, normally (about 99% of the time) i use sunoco, from the same gas station. as soon as i hit the gas getting back on the highway after filling up with mobil, i knew the gas wasn't as good.. i got a cel flash.

luckily i had a laptop hooked up and logging (i was tuning my upper load sites after acquiring a wideband o2) and i pulled over to see what was up. everything appeared normal, but suddenly i was knocking where i hadn't been before. i knew it was the crap gas, so i played it safe and pulled 2 degrees from the entire timing map and went on my way. the rest of the week up to today have been completely knock free, and it's been hot, and the a/c has been on a LOT.

fast forward to today... go back to sunoco, fill it up, put the two degrees back in the map, take it easy until the gas circulates through the rails, and romp on it.. all's quiet, which makes me .

you've got the main pros and cons to full standalone... the big one for most is the obd2 compatibility. apparently with the hydra phil has worked out the maps enough to get it to idle without problems. if you have a rex you can hold onto your cruise control.

if you want a turn-key solution, go with the reflash. it is the most "transparent" to the end user. in the scenario above, the reflash would have knocked just as my car had. in fact, it probably would have been a little bit more severe of a knock event. i knew i had just filled up, and i knew i had just switched to a gas brand i don't typically drive on/tune with, so after the VERY FIRST knock i knew what the deal was and i took aggressive steps to combat it. the oem ecu, with or without reflash, would need either a humungous knock or a lot of smaller knocks to pull timing on a global scale--but (and this is admittedly a big but) it wouldn't have required ANY input from me to do it, and certainly not a laptop, pulling over to the side of the road, etc).

yes, a reflash keeps the adaptive learning of the oem ecu. now, keep in mind that the tuner can program in just how much learning can/will take place. in that respect the tuner must really know their stuff when programming an oem ecu if they want to get the best results.

i also hold it to be true that regardless of HOW you determine the injector duty cycle and the coil signals, any piggyback/standalone/reflash will produce the same power. it's just that with a piggyback or standalone you are relying on the owner/operator/tuner to make adjustments, and with the reflash you are literally letting the computer make the adjustments for you. as such you have less control, as well as less responsibility.

keep in mind afaik there is no way to make the wrx oem ecu listen for knock above 5500 rpms... the sensitivity of the knock sensing can be altered, but not the fact that it doesn't work above that rpm. the sti ecu is different in that respect.

you can only have a max of two different maps on the reflash, which boils down to low boost and high boost maps. a utec can store 4 maps at the ready, and with a laptop an infinite number of maps can be stored. iirc, the xede is the same way.

the utec is a bit more versatile... spare solenoid control/water injection map, launch control (which is a TOTAL RIOT to play with! ) shift lights, hookup to a tuner (wideband o2 sensor with built in detcans, 2 each analog and digital logging inputs), etc. the xede has outboard interfaces but i can't comment on them personally.

finally, if you'd like to make global adjustments to fuel, idle, timing with your reflash you need to go with ecutek and you need to buy a licence for deltadash. and if you ever want to make significant mods to the car you will need to reflash. the good thing is that it also does obd2 codes and you can get a LOT of data about your car with its logging features.

cobb's accessport seems to be more convenient in this respect since you can reflash your ecu with another set of maps yourself. cobb has also been promising an "accesstuner" which would allow you to make adjustments on the same level as deltadash, as well as a "protuner" which would essentially be like a version of the ecutek reflash program, making very basic low-level programming changes to the oem ecu. however, as much as i'd like to see it and try it out i don't think accesstuner or protuner will be coming out for at LEAST a year.

hth
ken

 

Hi, I'm relatively new to the WRX scene. Although I've been reading this board for sometime, I mainly read clubwrx,wrxfanactics and nasioc. I can honestly say that this one thread has more insight and intelligence on the subject than most of those other boards' threads combined. Usually, comparisons of engine management end up in "cobb sucks" or "utec fried my friend's friend's car" or any other myriad of generalizations and half-truths.
With that said, I have the accessport and do like that its a reflash, since I am not a tuner nor have any aspirations to become one. cobb is one of the best companies to deal with, and often update the maps to make sure as many people as possible are happy. Some of the other benefits of the accessport are not as important but still are nice.. such as the anti-theft maps, econo maps and ecu boost gauge. It is quite a good buy for the everyday driver that just wants some extra power.
So, I really dont have any opinions to add to the topic, nor have I contributed greatly but I just wanted to say kudos to some level-headed wrx owner's sharing the wealth.

 

thanks josh for starting this thread and ride5000 for all the insight...i too am like"huh" and what should i do next for engine management, but yeah ecuteck reflash does seem promising now since i am not a big tuner nor would i really know how to do it...thanks for the info guys!!!

daniel

 

josh, is there any chance you could get a custom tune from a good shop nearby?

are there a lot of wrx owners in your area? maybe you could get together and pay a "big tuner" to come to town and give you all custom tunes.

ken