I redid the log for the last tune and called it -b as well as getting a log for the 9th tune. And Thanks! I had noticed that it seemed to hesitate a bit under light to mid load on the last tune. This tune seemed a bit better with the exception of between 1500 and 1900 or so under light load. Seemed a bit sketchy.
8th-log-b.hpl 9th-log.hpl
Elaborate on sketchy. I don't see any indication in the log of this. Good fuel trims and no KR. You have to be my eyes, ears, and ass. Just don't get too carried away with the analogy lol.
IAT's are really high. Anything you can do to help that out?
Last edited by SiriusC1024; 07-11-2023 at 06:59 AM.
Originally Posted by SiriusC1024
Yeah, IATs high, that has been mentioned. I did replace the sensor, although I did not relocate it. I looked at the factory plumbing and it is intact. The IATs gradually creep up and just stay there. There is the Throttle body, then the rubber boot to the the Plastic resonator/cover and the MAF, the other rubber boot then the Air Filter chamber and the fresh air intake that goes into the fender to collect air from behind the grill area.... I will dig into that a bit to verify that there is a path to fresh air thru the fender, instead of from behind the radiator.
It just seems like a flat spot/stumble/miss (without any pronounced shakiness like a dead miss) between 1500 up to maybe 2000 under light throttle. I feel it when trying to lightly accelerate, or when going up a slight incline. It used to be a lot more pronounced in the factory tune so it was always there. After the last couple tunes it was less and I thought it was gone, but I did feel it with tune 8. However it may have been there the whole time as I was more on the throttle before tune 8 as well. Tune 9 it even seems less. That is why I re-did tune 8 log, in case there was something there. The second tune 8 log was done after the truck was fully warmed up, the first one, not so much.
To give more information, I had a bad Knock sensor that wasn't throwing a code on my normal use scanner. I wound up replacing the Wires, Cap, Rotor, Distributor, O2s, and MAF during the process of figuring that out. SO, all of that stuff is new. The new knock sensors were an immediate improvement and I got another 500-1000 miles before I spun the rod bearings.
Ah I think I see what's going on. Log 9. At the engine speeds you're talking about there is a spread between B1 and B2 LTFT's of 5-6%, with B2 being richer. STFT appears to be compensating some. Anywhere else and they are close.
This could be an intake gasket leak, but I'd expect to see differential at any low pressure (high vacuum) condition. Being that it's also dependent on RPM I'll speculate that it's something like the EGR valve.
B2 is throttle body-side. B2 runners draw across from B1 side of plenum. That's where the EGR is located. B2 is pulling fuel, meaning that it isn't receiving enough air in relation to fuel. Exhaust gas is inert.
454 intake.jpg
Whatever the cause, and there may be nothing wrong at all, I can't really tune it out. There isn't anything like independent MAF or VE tables for B1 and B2.
Might be able to find a happy medium if you log for a long duration around that area. It would be best to check on the parts before doing that. There isn't much spread in other locations.
Last edited by SiriusC1024; 07-12-2023 at 07:43 AM.
This is absolutely something I can live with as long as it isn't a symptom of some impending doom! I actually suspected the EGR honestly, just didn't want to plant the seed. Motor.jpg
As I mentioned, it is minimal and if it isn't an issue in the stats, I am good with it.
I think it'll be fine.
The only thing wrong as far as safety goes is the knock sensors are disabled. Why is that?
Interesting choice in colors. I kinda like it because it's so different. Is that grabber green I see? What's it look like sitting in the engine bay?
Last edited by SiriusC1024; 07-12-2023 at 06:44 PM.
Mystery Machine.PNGIt is the colors of the Mystery Machine! Because it's a mystery what's under the hood... lol, actually those were the only colors I could get quickly besides Orange and Black...
The knock sensors were disabled by accident as in I didn't do it. Can you re-enable them?
Thanks.
Underhood01.jpgUnderhood02.jpg
Haha. That's pretty cool.
Blue header paint, and it isn't discolored from heat? Huh.
The knock sensors are wired in right?
Last edited by SiriusC1024; 07-12-2023 at 10:03 PM.
IMAG0501-20191210-211849474.jpgHeaderPaint.PNGThanks! Manifolds painted with VHT flameproof which I had to bake at 200, then 400 then 600 degrees for curing. The underhood pic was from today so it is holding up. The knock sensors are wired in and connected. (and new). Everything else on the truck was/is new when the engine blew, so I had to do something other than just stock replacement. New (used, sandblasted, painted with two coats of por15, tie coat and then por15 topcoat) frame, complete rolling chassis, Transmission, rebuilt front differential and transfer case. Everything works except yesterday the 'lock' feature on the remote start stopped working... Even the heated leather seats and rear heat/AC work.I did it all myself except for the transmission. Was fun replacing the frame in the driveway without a lift or garage!
Last edited by oldpartsnrust; 07-12-2023 at 10:20 PM.
Knock sensors aren't showing because Knock Retard isn't being logged. That's all. I assumed since no DTC set for knock that you had disabled them. Factory has it like that, too. Plus, I'm used to KR being logged by default. I should have been paying better attention. Add that channel on the next log. I'd like to enable HO spark, but I was worried about no knock being detected.
That frame replacement looks like quite a challenge. I can tell you put a lot of work into this. I'm glad to contribute.
I am glad you are contributing!
I managed to remember to get a ton of pics of the project as it took so long and the work was being done mostly outside so weather was a factor. Usually I forget to document projects! It started with a fuel leak which turned out to be a rusted out gas tank. When I was swapping out the tank my jaw dropped at the state of the frame. I think maybe 10 lbs of rust fell off just doing the tank. Then I saw the lines were wasted and the more I looked the more concerned I got. I was piling 3 kids, 2 dogs, all their luggage as well as my wife and I in there. So I pulled it off the road and cancelled any towing till we could address. The choice was between replacing or repairing. Replacing a tow rig that had a 454, leather, dual a/c & heat, tow package and basically every option turned out to be unaffordable unless we went really old, then I would be fixing that too! So, frame replacement it was.
IMG_7360.jpg
Notice the high dollar beams and columns? Totally safe!
IMAG0525.jpg So, how long till these let loose? Rear axle bolts.
9th-log-kr.hpl
Ok, got log with the KR included.
IAT's are really killing it. Instead of butchering the spark table I adjusted IAT spark and multiplier. Next I'll fine tune the base table if needed.
So it seems strange to me that the IAT should be so high as it is supposed to be pulling air from the area between the passenger side inner fenderwell and outer fender. I was looking into 'cold air intake' and it seems to pull air from directly under the hood, but with a shield facing the motor.... Not that it would seem to block the hot air, but only the direct radiant heat from the exhaust manifold... Not seeing how it does anything other than relocate the IAT sensor and open it up to more underhood air? I have some header wrap I am going to try to wrap the existing intake to see if that does ANYTHING at all to lower the temps.
Last edited by oldpartsnrust; 07-13-2023 at 07:37 PM.
Almost any cold air intake kit is a joke. It is strange that IAT's are so high. Maybe it's reading incorrectly, but you'd have to figure out a way to check for sure. Other thing it could be is the increase in cubic inches. If it's just that then I'd go the other route and work the base table. For now what I'm seeing is excessively hot air, so that's what I'm going with.
I am not looking forward to dropping $300 on a 'kit' that doesn't look like it really does anything. I will dig in further to the actual source of the current 'fresh' air as it is supposed to come from outside the engine compartment as it sits. I disconnected the IAT sensor and it went to -40 and when I initially start the vehicle it is at current ambient temp. It just seems to creep up, lagging the engine temp by a bit until it is like 130+. If I drive it on the highway it comes down a bit, but not as much as I would expect and it does not occur when I am in the 'local running around' mode gathering logs .I am wondering if a lot of the heat is being passed from the rubber intake hose to the sensor. I will see what the wrap does, if anything. It should help that my wife is a Boeing "ECS" engineer (Environmental Control Systems)! Maybe I'll ask for her input if I can't come up with anything. I suspect there was some plumbing that got the fresh air to the intake and it is leaking/disconnected/missing.
ok loaded tune 10. Will try to look at the intake and get a log tomorrow (later today).
Do you know anything about the difference between roller tip rockers and stamped stock rockers in terms of noise? I have what I think is possibly the 'sewing machine' noise that I can hear and is ok with me, but I hear an obvious valvetrain noise from like 4000 to 5000 which seems concerning, but the engine doesn't seem to have any issue with power or stumbling or anything detrimental other than 'yelling at me'. I did put a bigger cam, bigger injectors and roller tipped rockers in all at the same time.... Having never dealt with any of those before.
Thanks!
Last edited by oldpartsnrust; 07-14-2023 at 12:16 AM.
I know LS stuff a lot better, but my first guess would be springs. They have to be higher rate and preferably beehive. List all the valve train components you installed and P/N's.
I'm a big fan of PAC. Ovate wound, shot peened, beehive. Something like this:
https://www.racingsprings.com/index....ing-11192.html
Last edited by SiriusC1024; 07-14-2023 at 01:14 AM.
It was a comp cams complete kit,which did have the beehive springs. Funny looking too! And they were a lot stronger than the stock ones I took out. Plus I added the rotator eliminators as well as Adjustable studs, lock nuts, and the roller tipped..
Xtreme Energy Computer Controlled 212/218 Hydraulic Roller K-Kit Chevrolet Big Block GEN VI
COMP Cams Hi-Tech Rocker Arm Studs 4514-16
COMP Cams Valve Spring Locators 4779-8
COMP Cams Magnum Roller Tip Rocker Arms 1411-16
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