6.2 swap thread
- Thread starter ls1frc
- Start date
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Figured I'd give an update here
Truck has been running pretty well. I was struggling with some idling issues, but I think I have it ironed out. The stock 6.2 tune was causing it to surge badly intermittently and always seemed to happen right when I picked up my son from school. Embarassing. So I went back to a bone stock 5.3 idle parameters, and changed just the bare minimum. Added some base idle air and halved the deceleration airflow (makes it take longer for RPMs to come down). Now it's running perfectly (fingers crossed).
I also took off my flex fuel line fittings and added some Earl's conical seals to it. This seems to have fixed any leakage. Pretty disappointed I had to do this though.
Got the new Mishimoto installed and all is well so far, no leaks or orange stains.
My only complaint about the truck is these expensive Johnson lifters are still very noisy on cold start. They bleed down more than any lifter I've used. I am very disappointed because I spent the extra cash for a known good brand. It only does it in sub 40 degree weather and only lasts for a few minutes, so I am just going to live with it. No way I'd pull the heads just to fix that. With spring around the corner, I won't hear it. When warm, they are very quiet and the truck runs great. I added a quart of marvel mystery oil to my crankcase and I will run that for a bit to see if it's possible one lifter had some grime in it or something. I've spent like $150 on oils/filters to try to narrow it down. Once I drain this oil, I am going to run Mobil 1 Extended Performance and do long OCIs and be done with it.
I still need to spend more time dialing in WOT, but man it's feeling very strong. The Corsa definitely picked up a good bit of HP. Even with the 5.5 0-60 time, it would not break the tires loose in 1st gear. Now it will squeal them from a low roll. The stock exhaust was very restrictive.
Truck has been running pretty well. I was struggling with some idling issues, but I think I have it ironed out. The stock 6.2 tune was causing it to surge badly intermittently and always seemed to happen right when I picked up my son from school. Embarassing. So I went back to a bone stock 5.3 idle parameters, and changed just the bare minimum. Added some base idle air and halved the deceleration airflow (makes it take longer for RPMs to come down). Now it's running perfectly (fingers crossed).
I also took off my flex fuel line fittings and added some Earl's conical seals to it. This seems to have fixed any leakage. Pretty disappointed I had to do this though.
Got the new Mishimoto installed and all is well so far, no leaks or orange stains.
My only complaint about the truck is these expensive Johnson lifters are still very noisy on cold start. They bleed down more than any lifter I've used. I am very disappointed because I spent the extra cash for a known good brand. It only does it in sub 40 degree weather and only lasts for a few minutes, so I am just going to live with it. No way I'd pull the heads just to fix that. With spring around the corner, I won't hear it. When warm, they are very quiet and the truck runs great. I added a quart of marvel mystery oil to my crankcase and I will run that for a bit to see if it's possible one lifter had some grime in it or something. I've spent like $150 on oils/filters to try to narrow it down. Once I drain this oil, I am going to run Mobil 1 Extended Performance and do long OCIs and be done with it.
I still need to spend more time dialing in WOT, but man it's feeling very strong. The Corsa definitely picked up a good bit of HP. Even with the 5.5 0-60 time, it would not break the tires loose in 1st gear. Now it will squeal them from a low roll. The stock exhaust was very restrictive.
mikeyss
Full Access Member
You may be hearing piston slap. There is a coating on the piston skirts that wear off over time and cause a noise at start up. However, I read reviews on Johnson lifters saying they are noisy on startup. It's one of the reasons i didn't buy from them.
It's not piston slap, I have that too. That's a hollow sound. This is straight clicking, and it causes it to even misfire sometimes because the lifters are not actuating properly. It's annoying as ****. It's something I will only need to be annoyed about 3 months out of the year. I am still going to send them a video so I have the paper trail though in case I do decide to warranty them.
I wasn't happy with their customer service. Was painful talking to whoever helped me. Kept harping on preload. Thing is these are dropin lifters with .200 travel, preload really isnt' that important. I did .037 preload and .062, no difference.
I wasn't happy with their customer service. Was painful talking to whoever helped me. Kept harping on preload. Thing is these are dropin lifters with .200 travel, preload really isnt' that important. I did .037 preload and .062, no difference.
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Is it all of the lifters or just 1 or a few? Bet they quiet down after a few thousand on the clock.
BTW- I'm very happy with the Morel's you recommended to me. Very quiet all the way around, even on cold starts. Thanks for that.
Np. I wish i stuck with them lol.
They all clack like first start after a cam swap every morning for a few minutes. My morels were also loud on cold starts and actually did get quieter over time so we will see.
Relocated IAT sensor fixed the erratic idle. Pretty happy about that.
Basically reads artificially high after sitting with a hot engine bay and just sitting there idling while waiting to pick up my son really cooked it. Leads to a lean condition and the idle randomly dropping then over correcting. Very annoying but seems to be fixed now.
Basically reads artificially high after sitting with a hot engine bay and just sitting there idling while waiting to pick up my son really cooked it. Leads to a lean condition and the idle randomly dropping then over correcting. Very annoying but seems to be fixed now.
Relocated IAT
Clean maf
Tweaked 02s to be less reactive on the fuel trims
Rock solid idle, perfect drivability and now better MPG than the 5.3 by a lot. This is my normal drive to the stores, mix of some 45 mph highway and stop lights. 5.3 normally got 13 mpg.
Clean maf
Tweaked 02s to be less reactive on the fuel trims
Rock solid idle, perfect drivability and now better MPG than the 5.3 by a lot. This is my normal drive to the stores, mix of some 45 mph highway and stop lights. 5.3 normally got 13 mpg.
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