I just peaked at the log and noticed there is some more KR than I would expect. What fuel is in it now?
I know you have been working with others here and I'm not here to high jack their work, just making an observation.
This may be a case of needing to listen to the engine with the proper equipment to verify if the knock sensors need tuning.
Any recommendations on the lifter preload? I used 1/2 turn after zero lash... they are P/N: 17120061 GM Performance lifters with more oil to the rockers. Purchased as a kit
https://www.gmperformancemotor.com/parts/12371056.html?srsltid=AfmBOopHojDR3o0zyOlpQV2ePQQb 0M76stFpu76rtdhEuhzNuq0zgV-S
I just read this whole thread! With the amount of time and patience you have in this thing, I hope you get it the rest of the way ironed out and get to enjoy it this summer!!
In my opinion, when your not dealing with tuning a race car, anywhere between zero lash at operating temp. and not hanging the valve open when it's cold will work just fine. With that being said, I usually shoot for 3/4 of a turn passed zero lash, which is obviously in the middle of 1/2 to 1 full turn, assuming your using stock thread pitch rocker studs.Originally Posted by oldpartsnrust
Thank you! I really hope I am approaching the finish line,,,, again. I need this thing to recover my boat from upstate NY where the harsh North Country has taken a lot of the life from the upholstery and decking. I plan to bring it back down here and refurb that next! I only have old things that I keep on the road/water as today's products don't seem to last anywhere near as long and are just so ridiculously expensive! Thanks again!
So I am a bit concerned that there is still knock showing...The quench should be 0.044" and compression about 9.8:1, I believe. I filled with fresh 92 octane but it had about a 1/4 to a 1/2 tank of old fuel as well. I don't plan to run this thing at high RPMs and it has a towing cam and in stock form is more tailored toward lower RPM torque. Is there a way to make the spark ramp a slight bit less aggressive and maybe get rid of that? I will dump a couple cans of octane boost in there and take it for another spin to see if that changes anything. Specifically to see if this is truly knock instead of other noises causing readings.
Last edited by oldpartsnrust; 01-30-2025 at 12:14 AM.
My guess is it's false knock based on what I saw but, you deff. need to verify it. One way is to do something similar to what you are going to do, but I would probably drain the fuel and put 100 octane unleaded fuel in it for a test. Another way is to build yourself a set of knock ears using 3/8 rubber tubing, a piece of 3/8 copper tubing smashed down on one end so you can drill a hole in it and bolt it to the block. Run the rubber tubing from the copper block adapter into the cab. Use a cheap set of ear protection ear muffs, drill a hole into the ear cups and feed the tubing into the ear cups. Then go drive around. You will be amazed how well you can hear what's going on in the engine.
14-B.hpl
Changed oil, longer run today, couple stops and idling. Did NOT put in the octane booster yet. I can hear the rockers pretty good. I may want to give them another 1/4 turn just because. Felt strong. I don't really intend to put any high revs on this as it is my tow vehicle. Seemed really nice. Drained oil, there was some glimmer but not like the last time I rebuilt it. This was the first oil change so I am not panicking and I expect there should be something in there for a couple / few changes right? All in all, so far so good!
Is Sirius still around? I am curious on the interpretation of the logs and next steps of any additional tuning if needed? Also, another question. Should I assume that the rings are fully seated after these runs around and mid throttle bursts and such?
Thanks all!
Last edited by oldpartsnrust; 02-01-2025 at 07:48 PM.
He got into a big altercation with a troll, ended up breaking some (maybe all) of the site rules, and got banned.
Oh no?! Really? That really sucks. Does anyone have any contact info? I owe him bigtime and would really like to square up. Man, trolls suck. It is a shame that people are like that.
Last edited by oldpartsnrust; 02-01-2025 at 08:34 PM.
I would agree with you that it sucks. He helped quite a few people on here. The guy that pushed him over the edge was not even an HPT customer.
I did find where one of my engine mounts is hitting the frame. I couldn't hear it, but I see some obvious witness marks. As big as this truck engine bay is it is not roomy with this 496 in there!
This shows the oil pressure idling, and revving while hot:
http://garnetvalleydrivers.com/SuburbanProject/Engine-v-3.0.mp4
This is the project BEFORE the motor blew and is why I decided to bother with the motor as I already invested this much in the vehicle (This is a link to a word doc, so it may auto downloaded, or even be blocked by your IT or browser):
http://garnetvalleydrivers.com/Subur...anProject.docx
Buddy of mine gave me some space on his server for files.
Last edited by oldpartsnrust; 02-03-2025 at 10:47 PM.
Ok, so this is the filter after about 5 - 10 miles on it for the first oil change with what I believe were enough mid throttle pulls to seat the rings. Does this look like anything concerning? The oil had a goldish hue with sparkles, but wasn't grey like the first go round rebuild.
OilFilter.jpg
Looks normal to me based on how the engine was assembled. If the debris does not get less and less each time you cut the filter open then you have a problem. I would cut it again at 100 miles, then assuming it has less debris at 100 miles than it did at 10 miles, then I would check it again at 500 miles. Assuming it has less at 500 miles than it did at 100 miles, it's good to go.
Thank you.
So I literally have the exact same noises that I had last time. The rocker/lifter sounds. I think this is what is causing the knock signal. It is hard to describe, but I think it is the CompCams Extreme Energy cam and there is nothing I can do about it besides swapping to a different profile cam. I say this because I swapped out the roller tip rockers for extra articulation stamped rockers that allow for higher lift cams to work properly and I get the same noises. So, are there any ways to detune the sensitivity of the knock sensors or anything? I don't want to do that just yet, but just asking. I do plan to get a listen to the actual engine using some listening method, either mic or copper tube, hose, headphones stuff.
Looks like you can only limit the amount of retard with this PCM.
Is there a better quality, i.e. better targeted knock sensor? I guess these are really simply microphones SO probably not. I wonder if there could be some filtering applied like in a speaker system with the high-pass, 3 way crossover type dealio... Just sayin...
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