Japtastic141 Posted February 23 Report Share Posted February 23 Fairly standard RB26. Breathing mods and a couple of R34 N1 turbos. Better fuel pump and 550cc injectors. I wonder if what I'm doing is correct from a road-tuning point of view. I'm using the Aplha-N method. Just wastegate pressure at the moment which is 0.6 bar. After a bit of trial and error, I think I have a plan but I'd like to know if it's a valid way to do it. Started off with the base map from Link, smoothed it out a bit, and then did some pulls to make sure I wasn't too lean. Adjusted the main fuel a bit on the rich side to ensure this. Started the log and turned off OL and CL AFR control. Went for some pulls and tried to hit a lot of cells. The best way I've found was coming right down to 1000-1500 RPM and then doing a pull in 3rd, 4th or 5th gear holding the TPS at various points. So first pull at 10-20% throttle and hold all the way to redline. Then rinse and repeat for 30, 40, 50, 70, 100% TPS. This filled up the mixture map a good chunk and I now have some data to work with. I took a look at the results and applied corrections (from the mix map) to any cells that looked sensible and had a decent amount of samples. This made the map a bit spikey again so went ahead and smoothed it out a bit on the 3D map. Below is my map file and log before any changes and then my new map after I applied the changes. I haven't had a chance to go out again but will do soon so should have another log file in the next couple of hours. https://drive.google.com/file/d/19ITEiFUfCT3eb9Cgq0oGEKuD2q60PNdb/view?usp=sharing G4X R32 GTR.pclx Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 24 Report Share Posted February 24 Open loop lambda correction needs to be on for boosted alpha N. You will need to enable that and go over the fuel map again. Once you have the main fuel table giving decent results, then increase the boost to max and confirm the lambda still follows target. If it has restrictive turbines you will find it will drift richer than target at high boost, put negative values in the high boost/high RPM corner of the 4D table that is already setup in the base map if needed to correct this. Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Confused as I thought it was best to have these controls off when using the mixture map and doing the initial tuning of the fuel map to get it dialed in? I have a permanently installed AEM CAN WB that will do the CLLC after I tune it. I didn't intend to use the OLLC at all. Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 24 Report Share Posted February 24 7 hours ago, Adamw said: Open loop lambda correction needs to be on for boosted alpha N. You will need to enable that and go over the fuel map again. Once you have the main fuel table giving decent results, then increase the boost to max and confirm the lambda still follows target. If it has restrictive turbines you will find it will drift richer than target at high boost, put negative values in the high boost/high RPM corner of the 4D table that is already setup in the base map if needed to correct this. Alpha N Fuelling needs to be tuned at base boost , then Open loop lambda sorts of the fuelling when over base boost as Adam said above. If your fuelling is pretty tight to the AFR numbers you shouldn't need to make much of change to the fuel map. Open loop lambda sorts out the fuelling over base boost without any input from another map mathematical in the back ground A well set up layout will help with the tuning , on the above run at 55% throttle you map needs a lot of fuel out at low RPM more fuel from 3000rpm upwards any questions you only need to ask Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Thanks for that. So after I tune it with the above method I turn off OL and turn on CL? Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Turned on OL and did some more runs, has made things a lot richer. I'll spend some time looking through it all. Any suggestions welcome. Cheers. https://drive.google.com/file/d/1oY1bRkfRJWxRVo1jkZsReCGiZ8FVrP8F/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 24 Report Share Posted February 24 13 minutes ago, Japtastic141 said: Turned on OL and did some more runs, has made things a lot richer. I'll spend some time looking through it all. Any suggestions welcome. Cheers. https://drive.google.com/file/d/1oY1bRkfRJWxRVo1jkZsReCGiZ8FVrP8F/view?usp=sharing you now need to tune the fuel table to match the lambda table, you leave the open loop lambda tab turned on. Looking at your previous map file the fuel map is a long way from being tuned close. ; should look more like this I dont like the auto tune to rough a map out or to finally tune a car, this needs to be done manually using lambda versus lambda target (which is the same as overlay lambda numbers) pretty easy if you get a good layout set up to view the correct data. Happy to help if needed Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Thanks again. There certainly is a lot to learn and I appreciate the help. I'm learning a lot from EPA and HPA but nothing like speaking to an experienced tuner. Strange that I'm not getting that close to your 3D fuel map even after multiple runs and adjustments. If you have a decent layout file I could use that would be great. The other thing would be a target AFR table you recommend for the RB26. Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 24 Report Share Posted February 24 ABBEY 01_2024.llf5 Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Brilliant, thanks! I'm targeting a lot richer after 100 MAP on my AFR table so will tone it down a fair bit now I've seen yours. One thing I did notice was that at cruising speed / 100MAP, I was seeing around 900c exhaust temps at 14.7 so brought that down to 14.3 which improved temps. Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 24 Report Share Posted February 24 1 hour ago, Japtastic141 said: Brilliant, thanks! I'm targeting a lot richer after 100 MAP on my AFR table so will tone it down a fair bit now I've seen yours. One thing I did notice was that at cruising speed / 100MAP, I was seeing around 900c exhaust temps at 14.7 so brought that down to 14.3 which improved temps. What sort of ignition timing figures you seeing? any compensation on the timing figure working? IAt? Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Around the 20's on my 100% TPS to 7500RPM runs. Haven't tuned it yet. No compensation that I can see in the logs. Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 24 Report Share Posted February 24 2 hours ago, Japtastic141 said: Brilliant, thanks! I'm targeting a lot richer after 100 MAP on my AFR table so will tone it down a fair bit now I've seen yours. One thing I did notice was that at cruising speed / 100MAP, I was seeing around 900c exhaust temps at 14.7 so brought that down to 14.3 which improved temps. I wasn't clear enough regards EGT numbers while cruising , I think you running too small ignition timing figures, adding timing will lower EGT's far more efficiently than running a rich mixture. Your also running a static injection timing figure that will also affect EGT's/afr readings Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 24 Author Report Share Posted February 24 Ok great, will try adding timing for the cruise areas first. Do you mean turning this table on? If so, I haven't even looked into that yet so any guidance welcome. Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 24 Report Share Posted February 24 this is how a base map is set up. Have a read up in the help file. Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 25 Author Report Share Posted February 25 Yes, that matches mine. Thought you meant to turn the Injector Timing Table on so not sure what you meant by "Your also running a static injection timing figure that will also affect EGT's/afr readings" I'm wondering if I wasn't too far off tuning my fuel table but one of the main issues was that my target AFR's were way richer than they needed to be. This massively skewed my 3D map vs yours. I was just erring on the side of caution basically. The two pics below show the comparison between my guestimation targets and yours that I've now swapped to. I was also running a flat figure across all rows from low RPM to high. A stark difference! I'm still unclear on how exactly OLLC works within the Link platform. What is it referencing and how is it calculating what it needs to adjust and why did turning it on make my fuel so dramatically rich after around 50% TPS and beyond mid-range RPM? Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 25 Report Share Posted February 25 1 hour ago, Japtastic141 said: I'm still unclear on how exactly OLLC works within the Link platform. What is it referencing and how is it calculating what it needs to adjust and why did turning it on make my fuel so dramatically rich after around 50% TPS and beyond mid-range RPM? Overlay lambda is an add onto the fuel equation that helps when tuning Alpha N with a boost car. it needs the fuel map tuned closely to the Lambda figures to allow the fuel equation to work out required fuel quantity once running over base boost (if base boost is 0.8bar the fuel map doesn't know what boost your running OOLC does so it works it out for you. You can run without OLLC turned of but to run more than base boost you require another map configured to add the required fuel that more boost needs something like a 4 or 5d map with MAP versus RPM axis's set up. if you turn it on after tuning the fuel map the added extra equation will slur(offset) your lambda/AFR measurement. once the fuel map is tuned nice and tight you can adjust the fuelling by just adjust the OLLC map numbers not touching the main fuel map. once understood it is the way to go on a traditional fuel equation on a ALPHA N tune or a MAP based tune 2 hours ago, Japtastic141 said: I'm wondering if I wasn't too far off tuning my fuel table but one of the main issues was that my target AFR's were way richer than they needed to be. This massively skewed my 3D map vs yours. I was just erring on the side of caution basically. The two pics below show the comparison between my guestimation targets and yours that I've now swapped to. I was also running a flat figure across all rows from low RPM to high. A stark difference! Your find that a engine doesn't need a rich (fat) at lower RPM/load numbers. LAMBDA/AFR numbers are a personal choice but most people are around the same area, the numbers in my cal is something we have developed/worked with for years , we also will add fuel per gear/speed/ full load timer once the fuelling is configured for high speed, a car needs a richer mixture when running at high speed. Ignition also need work in relation to speed/load as well Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 25 Author Report Share Posted February 25 Thanks for all this. Starting to make more sense now. Been out to log some more this morning. Same map as before but with the new AFR targets you provided. I had a quick go at correcting it based off the logs but still not getting anywhere near the shape of your 3D map. I'll spend some more time later but any suggestions welcome. Cheers https://drive.google.com/file/d/14UriU8I6qr1UrozevN8wFD8O5cE-lYHR/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 25 Author Report Share Posted February 25 I'm wondering if my 30-year-old injectors are playing up and skewing my results. I did take them all out, clean them and test and seemed to be ok but you never know how they are performing under proper loads and not just on the bench. The figures I have for them could be completely wrong... Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 25 Report Share Posted February 25 So you can see at 6500rpm and 30% throttle you are 23% to rich, this is far to much for auto tune to work with , the fuel map needs some manual work to get it a little close. If you have my layout loaded, this screen shot is from wide band versus afr log , you can use this to manually get you fuel map closer. V at 60%ish throttle the fuel map is pretty close at 3000ish rpm, at 6000rpm your only around 10% rich at 90% throttle 2500rpm your 11% rich , 6000rpm around 9% rich hopefully this will help get and idea of how much work your map needs modifiying Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 25 Author Report Share Posted February 25 Thanks for looking at this. I looked at your examples and your manual calculations and also did my own on a few different places and the mixture map is very close on all the areas I checked but your layout helps a lot and I now have a better understanding of how to manual tune and interpret the logs better which is invaluable. I've been through and double-checked the mixture map vs my own calculations on your WB vs AFR LOG layout page and this I what I now have. I won't be able to do another log tonight but will tomorrow morning to test it and post the results. Not sure why it's still not looking quite like your 3D map and if you are saying the hundreds of RB's you've tuned mostly look like this (with similar mods to mine) then I'm not sure if I'm still tuning it wrong or something else is skewing it. Could it be the injectors? And could that be the reason I'm not seeing this area taper off as you'd expect? REV16 - G4X R32 GTR+OLLC ON-AMS AFR-2nd changes.pclx Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 26 Report Share Posted February 26 The map shape would say to me you might have fuel pressure issues as you needing to add fuel numbers to get the correct fuelling. The fuel map should look like the Torque curve of the engine. Torque will drop off at the top end so less fuel is needed. The map other than the issue at the top end looks far better than before. Do you still have the fuel pump voltage regulator controlling the fuel pump? maybe this isnt supplying 12v to the pump? Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 26 Author Report Share Posted February 26 Going to take one more look at this morning to make sure I've done the best job I can on the map and just to see if it turns out similar to last night's attempt for my own sanity! No, I've run a new cable directly from the battery to relay in the boot and bypassed the FPCM completely. Also fitted a new fuel pump around a month ago. Could injectors cause this to be skewed in your experience? Coupled with the fact the dead times may not be accurate... Quote Link to comment Share on other sites More sharing options...
AbbeyMS Posted February 26 Report Share Posted February 26 what's the battery voltage doing during the datalogs is it consistence? if the voltage is steady then dead times wont make any difference to the tune numbers Does the fuel pressure regulator hold Boost ID pressure? is the reg a stock item? Quote Link to comment Share on other sites More sharing options...
Japtastic141 Posted February 26 Author Report Share Posted February 26 Cruising and idle is 13.5v, steadily drops from the start of a power run, and ends at 13v minimum. It's what looks like a Nismo FPR and has been adjusted to run around 0.5 bar more than standard from what I can tell on my Greddy FP gauge. 3 Bar on idle, 3.6 bar on idle with vacuum pipe removed... 27 minutes ago, AbbeyMS said: Does the fuel pressure regulator hold Boost ID pressure? Sorry, not sure what you mean. Quote Link to comment Share on other sites More sharing options...
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