As I've been waiting on acceptance for this forum I've been doing research on what 5w30 oil I should start using in my RSX. This is my first time being here, thanks, I'm glad to be a part and I'm ready to learn lol. Anyway, I've had some bad experiences with my car, not necessarily the oils fault though. Two weeks after I got it, it spun rod bearing #1. I gave it to my mechanic, he replaced a bunch of stuff, rebuild the head even, I basically have a new engine besides the valvetrain, which only had 80k miles on it. The thing we did wrong was we machined the crank and put bearings in it to fit the crank. Really big mistake because in January, 3k miles down the road, #2 spun and while we were trying to keep this from happening again, we got a lightly used crank and all oem bearings. We found out it takes like 5 or 6 different size bearings used in conjunction, no wonder it spun. I should have the car by the end of this week, I'm breaking it in on conventional oil, then I'll run mobil 1 advanced full synthetic, like the stock engine would normally like for 1 or 2 oil changes after that. I put Royal Purple in it last time and I didn't really like the outcome. After these few oil changes I'd like to move up to something else and I need help finding something good. The car will be ran hard, I do plan on taking it to the track, but it will have the majority of its miles on the street.
So, I did pretty extensive research recently, it started from seeing this thread: http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2507806/1 I was interested in the Honda Idemitsu oil they were talking about in the beginning, but really the only thing good you can take from this is the Subaru Idemitsu oil, I can get it at the dealership. It's different from the old Honda oil, I believe the Honda oil was SM rated, the Subaru oil is SN GF5 rated, has a lower viscosity index though, but it's HTO-06 rated. The old Honda oil was thinner like the mobil 1, both about 170-175 viscosity index. I could keep putting mobil in it, but I really like the additive package in the Subaru oil, lots of moly and around 1000ppm of zinc show in the uoa's I see. I think mobil dropped the zinc count since my car was made. Neither mobil or subaru have a lot of magnesium in it, if they choose not to use it I'd probably like to stay that way, Royal Purple seems to have a lot of it, so definitely won't use it again. Others that I looked at are Amsoil ss and oe, Rotella T6, Eneos, and Redline. The only one I haven't seen ran in a honda k20 is Idemitsu, of any kind. It's been a while since you could get it at a Honda dealer and I highly doubt anyone is putting oil labeled Subaru in their honda.
Please tell me if this is a bad idea, it'll be a month at least before I do it anyway, I'm thinking about running 75% Subaru Idemitsu 5w30 full synthetic and 25% Mobil 1 5w30 advanced full synthetic and maybe even a shot (like literally a shot glass size, I'll have to find a good measuring cup lol) of zinc additive. My goal is to have most of the Idemitsu additive package (calcium, boron, phosphorus won't change much, molybdenum will mellow out, zinc will lower if I don't add any) and closer to the mobil 1 viscosity, then the zinc additive will keep it around a 1000ppm level. I will get a uoa for this if I do it.
Please help me out, I'm pretty paranoid, I want the best for my engine, especially at a good price lol. I'm still learning more about oil, I don't know the full effects of what everything does and the additive amounts I'm kind of going off averages from uoas and data sheets I see. I do know I want to keep zinc at about 1000ppm, I don't want to see 800ppm in my uoa although I have a roller cam. If you have anything else I should look at I'm will to spend $45/gal including shipping on oil, or travel to Kansas City, St. Louis, or Springfield, MO to get it, especially if it's cheaper.
So, I did pretty extensive research recently, it started from seeing this thread: http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2507806/1 I was interested in the Honda Idemitsu oil they were talking about in the beginning, but really the only thing good you can take from this is the Subaru Idemitsu oil, I can get it at the dealership. It's different from the old Honda oil, I believe the Honda oil was SM rated, the Subaru oil is SN GF5 rated, has a lower viscosity index though, but it's HTO-06 rated. The old Honda oil was thinner like the mobil 1, both about 170-175 viscosity index. I could keep putting mobil in it, but I really like the additive package in the Subaru oil, lots of moly and around 1000ppm of zinc show in the uoa's I see. I think mobil dropped the zinc count since my car was made. Neither mobil or subaru have a lot of magnesium in it, if they choose not to use it I'd probably like to stay that way, Royal Purple seems to have a lot of it, so definitely won't use it again. Others that I looked at are Amsoil ss and oe, Rotella T6, Eneos, and Redline. The only one I haven't seen ran in a honda k20 is Idemitsu, of any kind. It's been a while since you could get it at a Honda dealer and I highly doubt anyone is putting oil labeled Subaru in their honda.
Please tell me if this is a bad idea, it'll be a month at least before I do it anyway, I'm thinking about running 75% Subaru Idemitsu 5w30 full synthetic and 25% Mobil 1 5w30 advanced full synthetic and maybe even a shot (like literally a shot glass size, I'll have to find a good measuring cup lol) of zinc additive. My goal is to have most of the Idemitsu additive package (calcium, boron, phosphorus won't change much, molybdenum will mellow out, zinc will lower if I don't add any) and closer to the mobil 1 viscosity, then the zinc additive will keep it around a 1000ppm level. I will get a uoa for this if I do it.
Please help me out, I'm pretty paranoid, I want the best for my engine, especially at a good price lol. I'm still learning more about oil, I don't know the full effects of what everything does and the additive amounts I'm kind of going off averages from uoas and data sheets I see. I do know I want to keep zinc at about 1000ppm, I don't want to see 800ppm in my uoa although I have a roller cam. If you have anything else I should look at I'm will to spend $45/gal including shipping on oil, or travel to Kansas City, St. Louis, or Springfield, MO to get it, especially if it's cheaper.
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