Darth SpecB Posted December 28, 2017 Share Posted December 28, 2017 I have had my spec b for about over a year now. I personally rebuilt the motor about 6k miles ago in an effort to keep the cost down. (2600$ USD) However there were a few things I am concerned about, not knowing much of the previous history of the car. Since I bought her previously modified, I'm not sure how it came originally. For example, there appears to be no egr system. I have a complete magnaflow exhaust starting from the turbo with catless CNT downpipe, Perrin turbo inlet. Now the car was dyno tuned back in 2013. Turbo inlet was installed in 2015. There's no way for me to tell if the car was tuned for these mods and I'm afraid of running too lean/rich and causing damage to my fresh motor. Are the stock ecus readings accurate if I were to log with btssm? Or should I just bring my car to a tuner to check if she's running healthily with my current mods? Sent from my SM-G950U using Tapatalk Link to comment Share on other sites More sharing options...
Notorious Posted December 28, 2017 Share Posted December 28, 2017 The catless downpipe alone should warrant a tune as soon as possible to prevent boost creep. If you aren’t experiencing any boost spikes/cut offs yet at WOT then there may be an existing tune. Link to comment Share on other sites More sharing options...
FJuan Posted December 28, 2017 Share Posted December 28, 2017 Tune My wife's balls are delicious. Link to comment Share on other sites More sharing options...
Wasted Potential Posted December 28, 2017 Share Posted December 28, 2017 I have a Cobb Accessport, and I advise going open source haha. Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 28, 2017 Author Share Posted December 28, 2017 The catless downpipe alone should warrant a tune as soon as possible to prevent boost creep. If you aren’t experiencing any boost spikes/cut offs yet at WOT then there may be an existing tune.I am aware that both a catless downpipe and a aftermarket turbo inlet require a tune. My problem is, I don't know if there was a tune performed after the installation of the perrin turbo inlet considering it was installed 2 years after the dyno tune. The car was tuned with the existing exhaust set up. Is there a way I can verify the tune will support my current set up? Or that the tune is healthy for my car? Sent from my SM-G950U using Tapatalk Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 28, 2017 Author Share Posted December 28, 2017 I have a Cobb Accessport, and I advise going open source haha.Agreed! Sent from my SM-G950U using Tapatalk Link to comment Share on other sites More sharing options...
relative4 Posted December 28, 2017 Share Posted December 28, 2017 Re: "There's no way for me to tell if the car was tuned for these mods" - exactly which mods are you referring to? You seem to be saying it was tuned for the DP but not for the inlet, which was installed after it was tuned for the DP. So if that's correct, and the inlet is (are?) the mods to which you're referring, then no, you do not need a re-tune. Link to comment Share on other sites More sharing options...
rhino6303 Posted December 28, 2017 Share Posted December 28, 2017 If your closed loop fuel trims (cruise) are in line and you don't have significant afr error during open loop fueling (accel/boost) you don't need a tune for just the inlet. The inlet can increase airflow and require new maf scaling if your fueling is out of line. Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 28, 2017 Author Share Posted December 28, 2017 Re: "There's no way for me to tell if the car was tuned for these mods" - exactly which mods are you referring to? You seem to be saying it was tuned for the DP but not for the inlet, which was installed after it was tuned for the DP. So if that's correct, and the inlet is (are?) the mods to which you're referring, then no, you do not need a re-tune.Yes this is the answer I was looking for. Sent from my SM-G950U using Tapatalk Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 28, 2017 Author Share Posted December 28, 2017 If your closed loop fuel trims (cruise) are in line and you don't have significant afr error during open loop fueling (accel/boost) you don't need a tune for just the inlet. The inlet can increase airflow and require new maf scaling if your fueling is out of line. While logging, what should my fuel trims look like under open/closed loop? Should I be reading fuel learn, correct, or injector duty cycle? My a/f ratios are around 14.7+/-(.2-.3) at idle and around 14.0-7 At cruise. I haven't tested during WOT. Sent from my SM-G950U using Tapatalk Link to comment Share on other sites More sharing options...
rhino6303 Posted December 28, 2017 Share Posted December 28, 2017 While logging, what should my fuel trims look like under open/closed loop? Should I be reading fuel learn, correct, or injector duty cycle? My a/f ratios are around 14.7+/-(.2-.3) at idle and around 14.0-7 At cruise. I haven't tested during WOT. Sent from my SM-G950U using TapatalkIf you just do a learning view it should tell us the closed loop trims. Open loop is slightly more challenging. It will be dependant of your primary open loop enrichment fueling in the tune. You most likely have your open loop table tuned anywhere from 11.0-11.5ish during boost. Do you have a wideband that you can log? Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 28, 2017 Author Share Posted December 28, 2017 If you just do a learning view it should tell us the closed loop trims. Open loop is slightly more challenging. It will be dependant of your primary open loop enrichment fueling in the tune. You most likely have your open loop table tuned anywhere from 11.0-11.5ish during boost. Do you have a wideband that you can log? I can log using BTSSM. I can do a WOT pull and log that. Edit: I have the stock o2 sensors, but I don't believe it's a wideband. There is 2 sensors, 1 before down pipe, and 1 after. Sorry I'm not familiar with all of this tuning terminology. I will do some studying tonight. Sent from my SM-G950U using Tapatalk Link to comment Share on other sites More sharing options...
solidxsnake Posted December 28, 2017 Share Posted December 28, 2017 You can't accurately measure open-loop fueling without a wideband. Only closed-loop. One way to kind-of (potentially dangerous) check is to log fine-learn knock correction, feedback knock correction, and IAM, then run a WOT pull. In BtSsm, I'd set an alarm for FLKC and IAM if they drop below 2deg and 1.0 respectively. If the alarm goes off during the WOT pull, let off ASAP because the car is knocking. If you can make it through several WOT pulls with no knocking, chances are your fueling during open-loop is fine, or at least, not too lean. BTW, don't try and log too many parameters at once. You should only log what you need, because the more you have, the slower the logging (i.e. less samples per second). There's plenty of guides on what to log for certain types of diagnosis or tuning over at the Romraider forums. Link to comment Share on other sites More sharing options...
ehsnils Posted December 28, 2017 Share Posted December 28, 2017 If you don't know where the car is when it comes to tuning and mods - do a tune, just make sure that all "simple" items are fresh before the tune to not mess up the tune; Injectors, spark plugs, air filter, clean MAF and valve clearance. Running with an incorrect tune may result in burnt valves or even worse piston failures. Since you are catless you don't have to worry about burning the cat to oblivion due to a bad tune though. Link to comment Share on other sites More sharing options...
Phate Posted December 28, 2017 Share Posted December 28, 2017 If your closed loop fuel trims (cruise) are in line and you don't have significant afr error during open loop fueling (accel/boost) you don't need a tune for just the inlet. The inlet can increase airflow and require new maf scaling if your fueling is out of line. My inlet messed with the MAF scaling at low rpm/load. Thing acted all kinds of screwy puttering around town, and occasionally at low load on the highway, but runs great (if a bit rich) under boost/power. Link to comment Share on other sites More sharing options...
Wasted Potential Posted December 28, 2017 Share Posted December 28, 2017 I remember watching a video on YouTube. Kid used a K&N intake VS. A Cobb intake on the stage 2+ tune meant for the Cobb intake. Car would not even run haha. Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 29, 2017 Author Share Posted December 29, 2017 You can't accurately measure open-loop fueling without a wideband. Only closed-loop. One way to kind-of (potentially dangerous) check is to log fine-learn knock correction, feedback knock correction, and IAM, then run a WOT pull. In BtSsm, I'd set an alarm for FLKC and IAM if they drop below 2deg and 1.0 respectively. If the alarm goes off during the WOT pull, let off ASAP because the car is knocking. If you can make it through several WOT pulls with no knocking, chances are your fueling during open-loop is fine, or at least, not too lean. BTW, don't try and log too many parameters at once. You should only log what you need, because the more you have, the slower the logging (i.e. less samples per second). There's plenty of guides on what to log for certain types of diagnosis or tuning over at the Romraider forums. I set two alerts. 2 degrees for FLKC and 1 for IAM. The first log is closed loop (cruising at about 43-48mph) https://docs.google.com/document/d/18SCG-SgKaFCGpwYjjjW_sZmvHlqh3zqpLSEx-bEQOLc/edit?usp=drivesdk The second log is open loop (WOT in 3rd gear via 6 speed transmission) https://docs.google.com/document/d/17705boIDk6KS93JhIWaQXP2CALYwOa8jeyQS2PkGJlI/edit?usp=drivesdk IAM seems to be a consistent .938 Whats concerning is that FLKC reported -3.5 from 5580 to 5677 rpm. Should I be worried? Sent from my SM-T350 using Tapatalk Link to comment Share on other sites More sharing options...
Wasted Potential Posted December 29, 2017 Share Posted December 29, 2017 Do a few logs and make sure they are consistent if the alerts are not triggered. All heat shields removed? Only fine knock I got was low rpm and building into boost. Link to comment Share on other sites More sharing options...
solidxsnake Posted December 29, 2017 Share Posted December 29, 2017 I set two alerts. 2 degrees for FLKC and 1 for IAM. The first log is closed loop (cruising at about 43-48mph) https://docs.google.com/document/d/18SCG-SgKaFCGpwYjjjW_sZmvHlqh3zqpLSEx-bEQOLc/edit?usp=drivesdk The second log is open loop (WOT in 3rd gear via 6 speed transmission) https://docs.google.com/document/d/17705boIDk6KS93JhIWaQXP2CALYwOa8jeyQS2PkGJlI/edit?usp=drivesdk IAM seems to be a consistent .938 Whats concerning is that FLKC reported -3.5 from 5580 to 5677 rpm. Should I be worried? Sent from my SM-T350 using Tapatalk Haven't looked at the logs yet, but in general, having FLKC means the car detected knock at the given load/RPM range enough times to think it's a chronic problem, and is pulling timing in that condition always (use BtSsm to get a "learning view" to see what I mean). That could be bad, but if its at low load/RPM, then it could be due to false knock. Link to comment Share on other sites More sharing options...
Darth SpecB Posted December 29, 2017 Author Share Posted December 29, 2017 So it looks like im getting knock around 4400 rpm (-2.19) to 5600 rpm (-3.50). Looks like i should get a tune cause I'm possibly running lean or causing detonation. Sent from my SM-T350 using Tapatalk Link to comment Share on other sites More sharing options...
solidxsnake Posted December 29, 2017 Share Posted December 29, 2017 Yep, that's a good assumption. Those are places you definitely don't want to see knock. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted December 29, 2017 Share Posted December 29, 2017 Before you get a tune though, carefully check if you have any pre/post turbo leaks just to be sure. Your trims are almost all in the negative, meaning the ECU is detecting you are running slightly rich, and as a result is pulling a bit of fuel. This happened to me a couple of times and it was due to a throttle body hose which was not sealing very well. But my fuel trims were way more negative than yours. Then again, it may also come from a bad tune. In any case, just double check. It's good practice. Link to comment Share on other sites More sharing options...
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