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Yeah stock heads and head gasket, stock lifters.
The hardened pushrods are slightly shorter than stock I believe but I don't have the packing slip or info on them handy.
I purchased the cam package through a vendor I won't mention untill I can confirm if the package they put together for me did damage or not.
As far as going forward goes, assuming the Pistons are still in usable shape.. what do you see being the best option? New / different lifters? They are the original lifters with 98,000 miles on them. Or could I possibly make it work with a thicker head gasket for now?
Well for starters, IF you have piston to valve contact, I assure you you're going to have a lot more to worry about then changing lifters/head gasket. But beyond that, I am confused as to what information you're looking for. If you have PTV clearance issues, it's too late to remedy the issue. The damage is done and you'll likely need to rebuild your heads due to valve damage and replace pistons/machine reliefs, at minimum. That doesn't even include the potential damage to the bottom end from metal shavings that worked through the motor.
Now, if you do indeed have acceptable PTV clearance and the knock is from elsewhere, the first thing I would do is replace your knock sensors and harness. If the sensors are bad, you could be getting a false reading. While you're in there, I would also change lifters. 98K miles is plenty to warrant replacing. At minimum, LS7 lifters/trays would be a worthwhile swap. There are other better lifters out there you can go with if you'd like to spend some more cash (Johnson, COMP, etc). There is no need to go with a thicker head gasket if you have adequate PTV clearance and as I said, if you don't, it's too late.
If you do find PTV contact, after replacing all the damaged components and giving the motor a once over, you can run a thicker head gasket or machine reliefs in the top of the pistons. Both would provide more PTV clearance. Or you could always just install a cam with less lift. Keep us posted on what you find. For your sake, I hope it's just bad knock sensors or a collapsed lifter. Good luck!
Last edited by wscott62893; Jun 11, 2019 at 08:52 AM.
I'd be surprised if there were PTV clearance issues with that duration on stock heads and gaskets. As wscott said, you've got much bigger issues if you did in fact have PTV clearance problems.
Look elsewhere.
When you say you're "seeing knock" is that confirmed in data logs or you're just hearing knocking? If you're just hearing it, could be normal valvetrain noise with that cam and springs on stock lifters. That wouldn't surprise me at all.
That cam is fine that's not your issue. I have friends that put bigger cams then your in stock ls1 engine. If it hit the valves trust me you will know it. Ask me how I know. Lol
Last edited by helga203; Jun 11, 2019 at 10:18 AM.
looking at the stock cam that came out, the lifters deffinetly need to be replaced.
Not sure why I didn't catch it during the cam swap.
😧 Crank pulley side of stock cam Rear of stock cam
Please define knock, are you talking about picking up knock on the sensors or physical contact? Physical contact, as others have pointed out, would be very obvious by now if you have been running the motor.
We get that you see it in a log... But is it a quick knock spike and then goes away immediately? Or does it remain on the log for a little while under load? A quick spike is usually false knock and could be many things.
If it remains under load, then that is real and something seriously needs addressed.
looking at the stock cam that came out, the lifters deffinetly need to be replaced.
Not sure why I didn't catch it during the cam swap.
😧 Crank pulley side of stock cam Rear of stock cam
If you did not swap the lifters you certainly should, I would likely replace the new cam as well.
The knock in my logs is a quick spike, then it slowly dies off and goes away. (Seams fake) im Seeing up to 10 degrees leaving a dead stop at light throttle. And between 2 and 4 degrees at WOT. (3,200 to 4,400 rpms) I can't hear any knock myself though. It's just showing in the logs.
Ive only put about 200 maybe 300 miles on the new cam with the bad lifters that caused the wear in those pictures. I'm hoping I can just replace the lifters and run it without touching the cam again.
I know that's not the right way to do it.. but this time next year I will be replacing the motor so Im hoping ittl be alright. That cam swap was a pain.
Once I change the lifters If I'm still getting knock I'll fill up with some 110 unleaded to try and see if it's real or fake.
If you did not swap the lifters you certainly should, I would likely replace the new cam as well.
Swaped out the lifters, it must have been an imperfection in the casting when GM made the cam. All the stock lifters looked like new. No noticeable wear.
Piston to valve clearance is fine.
I decided to replace the knock sensors and harness while I was in there.
Hope to have it back together tonight.
If the knock is unchanged I think at this point all I can do is top off with some 112 to see if it goes away. If not, the sensors are getting desensitized a bit. I'm over this false knock BS.
Valve to piston clearance issue?
