Again, I would test run with a 40 weight and see how the oil pressure is at temp. If adequate pressures are attained with 40w, then no problem. Install an oil cooler and gauge to make sure the oil temps stay sane.
What are his clearances? My engine builder is a well known very reputable builder in the LS world. I've ask Texas Speed, Steve Morris, Borowski, AES to name a few and they all agreed with block material and clearances that im borderline 50 weight but agree Morel hydraulic lifters hold a tigh tolerance. 3 of 5 suggested trying a robust 40 weightAgree, some of these “requirements” are curious, especially the Xw50 requirement for something that’s not significantly different from a stock LS1… my brother’s aluminum-blocked LS2/3 hybrid that sees shift points of 72-7300 and makes well over 600HP at the crank uses Rotella T6 and even uses factory LS3 rocker arms on the 242/254 .621/.610 cam, albeit with Comp Cams upgraded trunnions. I forget which exact valve springs are on it, but they’re PAC beehives. We put that together in 2006 or so after an issue with his 383, and it hasn’t been out of the car since.
The general rule is to listen to what the engine builder says for oil choice, except when it appears likely that the engine builder is either confused because they specify something that’s not possible, or an idiot.
As a side note, I’d personally question Driven as well if their tech line will only share a viscosity at 100C, and it seems even just that little bit of info may not be representative if we are to question the viscosity measured during an independent OA.
I have not. Is HPL "high performance lubricants" and what is their association with HPL Superior Lubricants? Cause that latter is Harry Hruska. Ex owner of Precision Turbo that was right here in my hometown of Hebron, IN. I worked for him for a few years and if i had not signed a confidentiality agreement with thst company i could explain more. Too put ot short anyone who does business with that man is not someone who I want to do business with personally nor spend my money with.Did you speak to David @High Performance Lubricants ?
It’s been so long, sorry I don’t remember that fine of detail. Due to the previous issue on his 383, the machine shop turned the crank 20 under to get a usable journal. Other than that I’m drawing a blank. Like I said though, he is using a quality 40wt.What are his clearances? My engine builder is a well known very reputable builder in the LS world. I've ask Texas Speed, Steve Morris, Borowski, AES to name a few and they all agreed with block material and clearances that im borderline 50 weight but agree Morel hydraulic lifters hold a tigh tolerance. 3 of 5 suggested trying a robust 40 weight
You could run a couple qts 15W50 in with a stout XxW40 and be where you want to be.What are his clearances? My engine builder is a well known very reputable builder in the LS world. I've ask Texas Speed, Steve Morris, Borowski, AES to name a few and they all agreed with block material and clearances that im borderline 50 weight but agree Morel hydraulic lifters hold a tigh tolerance. 3 of 5 suggested trying a robust 40 weight
I agree, there should be plenty of great advice.WELCOME!
I don't have any information for you but others will soon chime in with great advise.