i see, i downloaded the Fine 'Ol Answer tune again, i might put it in and log a drive later just for shits and gigglesOriginally Posted by SiriusC1024
i see, i downloaded the Fine 'Ol Answer tune again, i might put it in and log a drive later just for shits and giggles
Cool. I'd like to see what it does for you. Use only the injector data portion of it. Just saying.
You should notice better transient response and perhaps idle. Hell, the tuner zeroed out the min pulse adder table and used an offset table from what looks like a stock Corvette file.
I expect fuel trims to be more positive since the flow rate is set higher. Remember the confusion of the tuner using the nominal 36lb/hr flow for the tune but then neglecting the fact that the rating is for 43.5psi not 58? Should be 41.57@58psi. Further, 36lb is for gasoline. n-heptane rating is [email protected]. This translates to 38.49@58psi. From that I factored in the 1.02 offset in flow for n-heptane vs gasoline to come up with the fine ol' values.
We'll see what all that's worth, I suppose.
Don't forget to use VCM Scanner to reset fuel trims after flashing the data.
Attached for those who want to follow along but not sort through the pages.
Last edited by SiriusC1024; 05-22-2023 at 09:56 AM.
what was procedure for resetting fuel trims?
these are the readings i took from the harness , and the wire color attached to each pin.....i can find some pinouts to show this to be correct and others that show it too be incorrect, so before i move on from this i still want to verify it is hooked up correctly. so what would be most helpful would be a pinout of what each pin requires for maf and for iat on the actual maf/iat sensor #25168491
i get that this code should or could be set due to disabling maf in the sd tune....what i don't get is why i didn't get the code earlier when this sd tune was first installed.....i doubt i missed it this long
maf-iat harness.jpg2009-05-25_155619_denali.jpg
update:
got this back from delphi in response to a request for a pin function/pinout
so it appears the wiring is correct
maf-iat pinout.jpg
is sensor signal and 5v reference the same thing?
Last edited by JR92RS; 05-22-2023 at 04:35 PM.
this is what it looked like just idling, let me know if it looks ok or if you see issues
Sensor signal and 5 volt reference are different things. One diagram is reversed from the other because the first is the plug and the second is the connector on the MAF. Sensor signal is for the MAF, 5V ref is for the IAT (voltage decreases with temp). In the hand-drawn diagram pin A should be 5V and pin B 0-5V IAT signal
Those two IAT wires are what would be needed if you decide to go the MAF removal route and use a standalone IAT. After it's wired adjust calibration settings for the sensor in the tune.
Nice work on getting the LTFT's working. STFT's are adding fuel like I expected. If you don't want to worry about redoing the VE put the flow rates back to where the tuner had it. Flow rates don't have to be particularly accurate btw. The VE table can be tuned to match whatever flow rate. Keep the important stuff - offset, short pulse, and min/default pulse values.
Clearing fuel trims is at VCM Scanner>Vehicle Controls & Special Functions.
Last edited by SiriusC1024; 05-22-2023 at 05:18 PM.
the only thing i found for resetting fuel was for long term fuel trims, i logged a drive with the same tune i used to idle....have a look to see how it's reacting to injector data provided
Still getting some heavy KR. I think it's best to lower spark instead of going with the tuner's assumptions that the knock sensors are too sensitive.
Attached is my recommendations file I posted earlier. Use parts of it if you want, especially spark (startup flare is a personal preference thing. I like it to sound agressive on start), upper rpm VE, and knock sensor levels. Leave the fuel and O2 stuff like you have it already. I think the changes will be beneficial otherwise I wouldn't have made them. Any questions let me know. If you don't want the suggestions I won't be upset it's your ride.
Run the car for a few days so that fuel trims accurize. You'll be needing to fine-tune VE, and I'll be happy to show you how to do it. Main thing we're looking for is that repairs to the wiring harness fixed the problem and that fuel trims don't do that weird stuff again that stalled your car.
Resetting fuel trims is to the right of the LTFT reset. See the On and Off buttons?
on mine i see something to the right but the info is not complete enough to tell what it is.....like the fields didn't populate enough, if you can take a pic of the screen you are referring to, or a screen shot that would be a big help
i took an hour long drive to get a good log, city streets and freeway, and while i see some knock retard it doesn't appear to be as bad as it used too. and it only happens during the transition from normal cruising too 80-100% throttle pulls, is this where i should be using the tip in tables
For tip-in try re-enabling burst knock retard at Engine>Spark>Retard. The multiplier table has been zeroed.
Here's what I'm talking about with the fuel trim reset. Yours doesn't have it?
fuel trim reset.png
no i believe thats the same screen where i see the off button and the end of some partial words above it, but the rest is missing, i'll try to get screen grab tomorrow of it, might have to re-download the software to fix this
so today here is how i was trying to tackle the knock that occurs as i transition into wot, using the video below i modified one of my charts then used it to pull timing out of the low octane table. have a look at the video if need be first, then i'll post 3 logs where i pulled advance. i'll try to upload them in order of attempt
video
https://www.youtube.com/watch?v=waic...72O8e&index=10
it appears to be getting better to me, or at least less occurrences of knock have a look and tell me if that's what you see as well.
and a question to anyone watching:
with a cammed engine running about 20-30 deg's of advance timing, is it normal when transitioning to wot for the timing advance to drop back down towards o deg at the same time?
It looks to me like transients don't have anything to do with the knock in the logs. KR is sustained.
I'm getting a dynamic compression ratio of 8.92:1 from the info on the engine build and cam card. This is pretty high. Remember this is a "small cam" which means small duration. DCR would be lower with a higher duration cam. I don't think there's any way around having to pull spark from the base tables.
Don't be a size queen about spark advance. You'll still make good power. Actually, you'll probably be making more than the dyno run because surely KR was pulling timing well below optimum during that run. Try the tables I recommended. Even they may be a little high.
If you haven't done so already, go a step colder on plugs and get some NGK TR6 plugs in there. Factory is TR5. Counterfeits are all over amazon and ebay.
Still running premium I hope.
Last edited by SiriusC1024; 05-24-2023 at 06:53 AM.
but if you look at the individual cells (example .32 thru .64 @2800 rpm) the knock is dissipating in those cells i have modified when comparing oct adj, too oct adj2, too oct adj3 logs
i'm not following you here at all....as the stock compression of an lm7 is 9.5:1 when using 862 heads, on mine they switched too using 243 heads which with no other changes would raise compression to 10.1:1....but they claim they switched pistons to a dish type that lowers it back down too 9.5:1 ......so if anything is off with compression it would be toward the higher side if they were lying about the pistons.(block and heads are verified as to what they are, pistons are the only ?)
what is DRC ?
and when you say no way around pulling spark from base tables.....does this mean what im doing is going in the right direction with pulling timing from the low octane table?
not sure what you mean here.....as i have no idea how much advance spark is normal for this engine, or what it wants too run right.
are you talking about the burst knock retard tables?
what are you seeing that made you come to the conclusion i need to run colder plugs?
yes
Ohh I didn't realize they used different pistons in the calc. Also looks .030 bored-over. For flat tops i came up with static compression ratio 10.25:1, dynamic compression ratio (DCR) 8.92:1. Estimated deck clearance .010. Head gasket thickness .051. Head gasket bore 3.790. Valve reliefs 3cc. Stock bore and stroke.
Basically what I said is do what you can with transient spark. Eventually you may have to accept that it's time to pull spark from the base tables. Yes, pulling spark from Lo is heading the right way. See, Lo won't be utilized until knock is detected. Spark then recovers based on knock learner then the process repeats. To be more correct, set the Hi table to where there's no knock with Hi octane fuel. Make Hi and Lo tables identical for that part. From there lower the Lo table by a decent margin.
The tables I mentioned were the base spark tables.
Hot spots may cause detonation. Going colder plugs is a good idea because it reduces chances of detonation. Colder plug means literally colder plug, as more heat is pulled away from the electrode. Too cold and it'll foul.
Last edited by SiriusC1024; 05-24-2023 at 09:57 AM.
yea they claim the stock piston was hypertectic (or something like that, cant remember) and they replace it with a dished piston to lower compression ratio
if i understand this correctly....transient spark=the octane tables, but i was under the impression in an sd only tune only the low octane table is referenced?
and 2 where is the base spark table and is that the exact name for it?
but what makes you think i need a colder plug, is it the fact there is knock being detected or for some other reason and can carbon buildup on the pistons cause detonation?
Last edited by JR92RS; 05-24-2023 at 10:13 AM.
It scales between Hi and Lo due to the HPT 1 bar Enhanced OS that has been applied.
sd ertt.png
Transient spark means spark adjustments due to quick changes in throttle. Things like burst knock.
Base spark is at Engine>Spark>Advance>Base>High Octane and >Low Octane
Running a NGK TR6 ( you decide platinum, iridium, ruthenium, etc.) on a cammed LS is a common mod. Plus, I'm seeing plenty of knock. For example: https://www.summitracing.com/parts/ngk-5141 Again, stay completely away from non-authorized distributors. I've been through that before and it's infuriating.
Carbon buildup can cause detonation for the same reason as wrong heat range plugs - hot spots. Carbon isn't an issue until it's thick and rough like charcoal. Yours isn't anywhere near that bad. Like I mentioned, if you want to see the metal on your pistons even after tens of thousands of miles add TC-W3 to the tank on fill-up to achieve 640:1 mixture or use something like MMO.
Last edited by SiriusC1024; 05-24-2023 at 10:20 AM.
mmo- marvel mystery oil? i like using seafoam....will that work just as good?
since you say it is still referencing the high octane table with the upgraded os, i will start removing from the high octane table today and see if the knock goes away
Last edited by JR92RS; 05-24-2023 at 10:57 AM.
is there any reason to have stft open loop disabled in an sd tune?
and i swung by jegs and picked up an aem wideband afr kit today, so i guess i gotta get that installed....good times
Last edited by JR92RS; 05-24-2023 at 02:39 PM.
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