I run Amsoil Z-Rod 10W 30 in my forged and boosted LS7.

I use actually use Amsoil 5w-50. Gets the oil up in the engine quickly when cold but gives me the thicker weight when hot as well as compensate for the larger clearances in the forged motor. You will get a lot of opinions on this I’m sure...

Just curious and would like to run something by you guys that relates to the thread. Would there be problems if 20W50 was used in a boosted LS7 with all factory parts in the bottom end? All bearings completely stock as well. If it would cause issues what would they be? I’m trying to figure out what actually caused some of my engine issues and if anything that was done to the car could be the reasons why this stuff happened. Trying connect the dots basically, now that the engine is out and all the parts can be seen. I’m having trouble trying to figure out if one mistake caused other mistakes or it’s just a fluke, coincidence or plane bad luck.

Yeah that’s exactly what the machine shop my engine is at said, then pulled up all sorts of different cars and what their main bearing tolerance was and how they varied. It started to get confusing but he point out how much less tolerance there is on and LS7 compared to some time the other engines. Basically LS7 is tight and shouldn’t have 20W50, way to thick.

frenchies and corvettes man!! That little dude in my avatar is Denver! Aka Denver the dinosaur 🦖 and a bunch of other names. Best dogs ever! Complete clown show 24/7

oh I am listening to the engine builder and I’ve done my own homework, I’m firing all these guys as soon as I drive it out of the shop, already taken all motor assembly away from them and brought everything to the engine builder, spoke with a new LS mechanic/tuner shop that I’ll be doing business with from here on out. These clowns are gonna drop the motor in and the blower all under my supervision and than I’m gone! If the logistics weren’t a nightmare to get the car with no motor and the rest of the pieces out of there I would.

I will 100% being going with my engine builder instruction on the oil my engine will use. I did do a ton of reading on oil and weights brands the whole thing. There’s a very lengthy oil test results and evaluation that gives hard facts only. I’m going that route, the oil that tested with the best wear protection is what I’ll be using. For my engine that will be Amsoil 5W30 synthetic. Now I’ll do a somewhat of a break in where Mobil one 5W30 conventional will be used for maybe 200-300 miles a change to mobile one 5W30 synthetic for another 300 Miles or so and that Amsoil will go in from then on. My research I saw the use of conventional oil first to let piston rings seat go either way, some swear by that and some say synthetic is just fine as well. My engine builder is a bit old school and likes the use of conventional oil for the first few hundered miles so I’m gonna let him do what he does, it just doesn’t matter to me and if it gives him warm and fuzzies and “ensures the rings seat” properly I’m not gonna push back on that. The first good decision I made on this build (minus what parts to use) I got lots of good input on parts from the forum, did my own searching to verify and each and every time I asked “which brand” for a specific mod my research confirmed those recommendations as well. Anyway taking the entire engine build to the engine builder/machine shop that had my block was the first smart move I made labor wise. One guy has everything and will assemble everything, he did all the hard technical work and his company owns it now. No finger pointing or blaming anything on someone else is possible now. I hope to have a “rebuild thread” up within a week or so, if at least one persons can learn from my mistakes I’ll be satisfied! Buying your first Vette and that vette being a C6Z with a ProCharger that had very low miles but the wrong supporting mods, doing a full on rebuild with such limited knowledge wasn’t the best idea honestly. I tend to go all in on **** when I do make big decisions. One day maybe I’ll tell the story of how I ended up retiring from a very large power company at 27 and joining the military(SOCOM) to be specific. All I was supposed to be doing was getting in shape for my wedding, a gym membership should have been fine......buuuutttt noooo.....I need to do a special forces prep training program to get in shape lol. Which lead to what’s going on 9 years in and still loving every minute. 🇺🇸

i did not buy this car pro charged. I built this car ground up. First a NA motor and I had a bad tune so I cracked #7 piston this is the reason I had this motor built. I did ask the motor builder and he said 10w30 or 10w40. More what I was asking was since I won't be running an oil cooler would a thicker oil help keep it cool but I think I got the answer on that where it will make it work even harder. So I will run 10w40 and see how it goes if not I'll change it up a bit. only reason I don't contact the builder more often is we don't see eye to eye. I was just asking to see who's done it and so on and has had good results

Well what I learned was each motor depending on what’s been done on the bottom end is going to determine what oil weight and viscosity will be best, and in some engines like a stock LS7 running 20W50 isn’t a good idea.

I seriously hope your build has went better than mine! Throw some details up wouldn’t mind seeing what you went with.