IAT's are definitely better.
IAT's are definitely better.
That log was run on the 8th. tune. Is that still ok for this latest tune to apply? I think I backed up to the 8th. because that is the first one with the knock retard logging enabled.
Ok, I am guessing you turned off the Knock sensor because it runs like it is supposed to! I do still hear valve noise, but not anywhere near what it was with the wrong length pushrods. Here is the log from today. I ordered some 'race gas' to mix in to boost a little bit more just in case. Did those calculations seem accurate? Also, I only run 91 or better octane (whatever is the best available). Would I be able to get lifters that would match these for the pushrod lengths?
This is from CompCams:
"Comp Cams Roller lifter 900-16. They are .842? diameter, weight 121g and the seat height is 2.66? "
Looking at "72920-16LUN LUNATI CHEVY V8 OEM REPLACEMENT HYDRAULIC ROLLER LIFTERS"
I would have considered putting the original back in after cleaning, but I 'modified' two of them for the clearance testing with the putty and there were indications of flaking on the rollers...
12-Lower-IATs-1-full-preload.hpl
Last edited by oldpartsnrust; 09-12-2023 at 10:08 PM.
Didn't mean to disable the knock sensors. I grabbed the last tune we did without checking. They're back on now.
The Melling lifters should work with those pushrods. Same case for the Lunati lifters. They are factory replacement as well.
Last edited by SiriusC1024; 09-13-2023 at 07:09 AM.
Well, it does confirm for me that the 'noise' whatever is causing it is being interpreted as knock by the computer.Originally Posted by SiriusC1024
Yikes, will be a bit before I get them:
sigh.PNG
I also was able to hear a heat shield rattling up under there... I will be looking for that while waiting for the lifters too.
I have also been researching to see if there is any way I assembled something incorrectly that could be causing lack of oil to the lifters. So far I came up with nothing. The oil pump does not use a gasket, the rear main has an o-ring in there, which I installed, the rear cam bearing seat has a groove cut into the block that provides the oiling up to the lifters which gets its feed from a passage in the block. The oil pressure gauge is tapped in the feed that leads to the lifters, so I can't see how there could be no oil pressure getting up there. There is minimal information on the Gen VI block as far as oiling diagram, but I do know that these have a 'priority main' oiling system.
Last edited by oldpartsnrust; 09-14-2023 at 01:08 PM.
At least you don't have to remove the heads to change lifters lol.
Silver lining.... I'll take it.
Well luckily (actually unluckily) I have the downtime to fix my wife's Sienna that blew out a plastic thermostat housing. Who puts plastic on motors? Oh yeah, just about everyone nowdays... But while I was under there I saw the transfer case leaking gear oil! It never ends!!!
Well, I know what my next project is anyhow.
Damn... they went on backorder....
Supply chain issues, I'm sure
So the plot thickens.... I got the 'backorder' notice from Jegs. However, when I go to their website, it says 'expected to ship directly from the vendor within 24 hours' for the availability. I called Jegs and they reached out to Lunati who said 'yeah, we have those in stock'. SO supposedly going out tomorrow. WTH?Supply chain issues, I'm sure
Supposedly shipping out tomorrow (Monday 10/02)
ugh, still not shipped.... Jegs shows 'ships in 24 hrs direct from manufacturer', but not to me!
Watch it'll ship DHL and be there by Christmas.
OK, so I didn't give up yet!!! However I bailed on the Lunati as they kept pushing out the ship date without any sort of feedback or notification from Jegs, or Lunati. The 'order status' was the same from the time I placed it. SO, I did a bunch more research and came down on GM Performance lifters and as an added bonus, they have increased oiling to the rockers. They should be here this week and it is now a race against the weather as I don't have a garage! I plan to rip her all down once I have parts in hand (I do already have the intake gaskets and such in hand) and swap the lifters. I will also do a borescope inspection of the rear plugs on the lifter galley to make sure they don't protrude into the passage and block anything. Damn this is time consuming (and money consuming). I don't think I broke anything yet, so I still have optimism!
Glad to hear you're back on track. I'll be here when you're ready.
Lifter update: Tomorrow, October 17 by 7:00 P.M.
I recall that when I had put in the drilled oil galley plug in the rear by mistake it pissed oil at an impressive rate on the flex plate, torque converter, trans housing and driveway so I don't expect to see any physical restrictions in the passages, BUT will verify to make sure. I really think I am just another victim of some bad new parts at this point. When I ran an automotive electrical shop I saw SO MANY bad parts that is was depressing. People would come in and say "I know it isn't the alternator because (shop x, y or z) replaced it, AND OF COURSE the alternator was the issue. It was probably the original issue as well. Customers were not readily accepting of paying for parts twice. Kinda like I won't be happy if the lifters are actually the problem. I will be happy the issue is fixed, no doubt, but won't be happy none the less. I will be even more unhappy if the issue is not fixed!
Parts in hand! I plan to at least start the lifter swap tomorrow, Sunday.
update: got here.
10222023.jpg
Last edited by oldpartsnrust; 10-22-2023 at 08:21 PM.
Got them out, soaking new and will check galley to make sure clear an open with oil flow using drill pump on Dist shaft.
Any luck?
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