Swapped a cam into a 6.0 lq4 and tuning has gone well so far but can?t get rid of stalling during parking situations. Is a 2500 gmc and seems like the power steering combined with the power brake booster load is too much to stay running. What tables should I be adjusting? Thanksnew spark tuning 1 2 degrees added.hplspark tuning added 2 degrees high octane.hpt
Last edited by RiggsStubbs; 12-05-2024 at 12:09 AM.
Post the .hpt and .hpl of the issue.
VE will need to be tuned rock solid. Depending on a cam you might need a wideband to truely get the shape of the VE table.
I'm assuming you have BRAF tuned in so that LTIT and STIT are 0 to slightly negative?
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Thought I had the VE dialed in with my wideband but maybe not good enough. I have tuned the BRAF a bit but never actually checked the fuel trims after I got it running. Will look into those tonight. also forgot to mention that during cold starts Im assuming while system is still in open loop it never stalls, not sure if that information helps with any advice. I will upload a log and the tune later today. Thanks for the help.
Post your tune and log.
Originally Posted by RiggsStubbs
This is not good advice for many applications.
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I prefer my ballenger afr widebands over a high mileage narrowband.
Yes it is. OL is a last resort. If NB bounding trend isn't correct then the attempt should be made to adjust PI settings. If control isn't achievable then resort to OL. A good spark map is critical.
CL is better in principle. It is actually a minority of cases where it can't be made to work, as large duration cams and radical intakes are in the minority of installations.
I have took builds where i didnt have a good startup map and tuned cl nb and then switched to ol wb. Has anyone used a high end combustion analyzer to confirm either cl nb or ol consumer grade wb are actually better than the other?
https://ecm-co.com/product/lambda-5220-system/
Someone donate some money so i can aquire this and test wb vs nb accuracy.
People seem to get hung up on precision when the point of a closed loop control system is stability and repeatability.
You are correct there. I never thought a couple percent on each side of rich or lean was a big issue or even measurable with most of our equipment. If the trims and wb error are less than 2-3 each way i figure its spot on. So many variables, cylinder to cylinder balance(we are getting an average), combustion efficiency, sensor location. Now if we had 8 widebands, 8 egt probes, 8 pressure transducers we could do some calibrating.
Well true, but I'm talking about variation in the inputs. Fuel varies even between gas stations. Temperatures change. Bank-bank imbalance that you mentioned. Even PCV and evap input. Things like that. Car that basically tunes itself in all conditions or one that needs constantly screwed with to make it right?
I have found that cheap or grocery store gas will run about 2% leaner than top tier.
I believe it. Probably more E. They have this crap at gas stations around here called E15 Super 88. It's rated 88 octane. Except what they don't tell you is that it's basically the "backin's" from the hydrocrack process doped up to octane spec with ethanol. Runs worse than 87.
Winter gas has a higher butane content, which means variance in the stoichiometric ratio.
Last edited by SiriusC1024; 12-04-2024 at 08:55 PM.
Humidity...
What is good advice for many applications?
Ethanol is cheaper than gasoline. Cheap gasoline=more ethanol.
.hpt and .hpl uploaded didn't have time to make adjustments tonight will tomorrow
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