408 stroker, 50lb injectors static no vac, long tubes, 10.5 compression, 4l80, tbss, 231/239 cam. I took timing out of it twice for the appropriate amount and it still registers the same amount needed to be take out. fuel trims look good a little rich. I've added octane booster no change. I don't actually hear any knocking. it just takes my timing out. not sure if I should try to take some sensitivity out of the sensors, never have done it either.
The knock sensors are not calibrated for the modifications. If you watch your plugs and all the other signs for knock, you can start desensitizing the knock sensors until they show 1 degree or less when you are sure there is no knock. You can start by maxing out the burst knock table (12760) to 7.9.
Your timing tables are a mess right now, deff. need smoothed out and represent more of a proper curve.
Octane booster will just foul the plugs. Mix a couple of gallons of 100 octane unleaded in it with your normal fuel you are using. Hopefully 91 or 93. If it still knocks it's false.
how do I get rid of false knock? I have 93 in it now.
You could follow post number 2 or send your combo back to GM and let their engineers evaluate each component of your new combo for the frequencies that are produced when knock occurs then re calibrate the knock detection system.
This is all assuming you don't have anything loose and rattling around on the engine.
I've smoothed out the spark tables a couple of times especially after adjustments. the tuner I was going to made a mess of it and I've been steadily trying to smooth it out. There isn't anything rattling around. The grg video said to zero the burst knock out and add 15 percent to the base sensitivity in the area that is causing the knock which is 3200 and beyond. I've done this procedure several times, all the way up to 97 out of a 100 and i still get the same result of 1 to 2 degrees of kr from 3200 to 3800 and more from 4000 and more it jumps to 7 plus.
edit: a combination of what abc said and the video I believe might be getting somewhere.
Last edited by smasher; 3 Weeks Ago at 11:18 PM.
Give it a shot.
idled really nice but leaned out immediately when i gave it some throttle. I would have run a log but it wasn't really drivable.
Last edited by smasher; 3 Weeks Ago at 12:19 AM.
Open my file. Go Compare>Open Compare File and select your original. Then Compare>View Comparison Log you can see what changes I made. Nothing to do with fueling other than setting Dynamic Airflow High RPM Disable from 1500 back to 4000 stock. Unless the VE table is dead wrong that shouldn't have made the difference you're talking about.
Fuel needed dialed in on the old tune you had anyway. What injectors are those, and do you have a datasheet for them?
yea sir that's the first thing I did was see what you changed. I left the fueling alone because whatever the local tuner did seemed to run a little rich. the injectors are 12613412 - 50lb L96 long story short on this truck I have had this truck tuned a bunch of times only to find that the reluctor wheel was messed up and after getting it fixed, I figured I might as well learn how to tune I've already spent too much on buying tunes. I have a data sheet for the injectors that I got from someone on here. but I put it into the pcm and it didn't run right so I put the original back in there. I'm guessing that I'm going to have to start completely over from scratch with the right injector data.
Here's the data:
https://forum.hptuners.com/showthrea...l=1#post766924
I've put it in the tune. Set to SD. Changed a few other things. Questions you or anyone lmk.
Load the tune, VCM Scanner>Vehicle controls & Special Functions to clear LTFT's. Log for 5 min (if possible) at temp. Stay under 3000rpm and don't mash it. Include B1S1 and B2S1 O2 sensor voltage.
Burst knock could be disabled completely. Burst knock will show up as knock on the log so you should log both to make sure what you are seeing is real knock.
But otherwise... this looks like a case of bad knock sensors to me. When they age they either get ultra sensitive, or completely quiet. But there is just no way any NA build should knock with that little timing in it.
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I disabled burst knock.
408 you'd think the sensors were changed when they had the engine apart. Maybe not torqued correctly.
Still, a lot in the tune could've caused incorrect spark mapping and/or fueling. I'd like to see how this does first.
ok sir here is the log of around 5 minutes i clicked the ltft fuel trim reset not sure if it worked or not didn't say anything and i put the gauges back on with the b1s1 and b2s1 sensors. It ran really lean and wanted to sometimes die when coming to a stop. as far as the knock sensors I tested the with a multimeter and hammer before I put them in to make sure they work and Torq them to whatever google said I think 18lbs . I didn't want to have to take the intake back off, so I made sure they worked. They are brand new and I just put them in Friday when the motor went back in. Is that the correct data for the injectors because i don't have a vacuum hose it's the c5 corvette regulator filter? I also noticed that you changed default injector pulse instead of min injector pulse. I think we have 2 different injector sheets.
Last edited by smasher; 3 Weeks Ago at 02:08 PM.
Data is setup for the non-referenced Corvette reg. We do have different sheets. I linked you what I used, and it's correct.
You forgot something:
Still was able to make corrections. I like to view the voltages to determine validity of data.Originally Posted by SiriusC1024
Same thing. Load, clear, log. This time come up higher in rpm and load. Also include Idle Adapt (STIT).
it ran really good but I had to put into 4wd to get into the rpms because its raining out right now. The idle was still catching itself when I come to a stop.
Here is the injector data someone on here gave me.
Yeah that's what I used, too. Your original file, however, did not. The only difference is the MinPW on the injectors. .760ms is fine.
Spark adjusted for KR.
VE for fuel trims.
Throttle cracker, follower, and spark over/underspeed for return to idle.
B1S1 is there, but B2S1 isn't lol.
oh ok I guess I'm confused on how the injector table is used then. I took the data out because it didn't run correctly when I put the data I there. I believe someone said the only thing that matters is if it has a vacuum to determine which data table to use because one says return less and the other says manifold ref. I'm not trying really to be difficult just trying to learn but wouldn't you use the bottom one?
Last edited by smasher; 3 Weeks Ago at 06:19 PM.
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