# Oil Discussion **URL:** \ **Category:** NYSpeed Automotive\ **Created:** [July 12, 2005, 7:35am UTC](https://forums.speedlife.net/t/oil-discussion/749 "2005-07-12T07:35:31Z")\ **Posts on this page:** 7\ **Page:** 2
**Author:** ![jeeves744](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jeeves744/32/7619_2.png) [@jeeves744](https://forums.speedlife.net/u/jeeves744)\ **Post date:** [July 22, 2005, 12:04am UTC](https://forums.speedlife.net/t/oil-discussion/749/21 "2005-07-22T00:04:48Z")
> [@joelster](#): > > Synthetic oil is superior to conventional oil, period. Synthetic oil is chemically engineered. The molecules are pure oil molecules. Conventional oil is REFINED from crude oil. They NEVER get ALL OF THE IMPURITIES OUT when they refine it. When you run your motor for a long period of time between changes or run it really hot in the summer, these impurities will begin to cook and char and turn your oil extremely dark. Ever remember seeing that old Mobil 1 commercial where they take the 2 oils and cook them in a frying pan? At 500 degrees, the conventional oil turned into a black syrupy substance. The Mobil 1 still looked like light brown oil. I know what your saying right now, “but my motor runs at 200 degrees, so I shouldn’t have to worry”. Well, your coolant may be at 200 degrees when your motor is running but your combustion chamber is well over 1000 degrees when it fires, and there is a glaze of oil on the cylinder walls directly under the flame front. The sybthetic is just extra insurance IMO. You can go much longer between changes with it too. So a synthetic change will run you maybe 30 bucks compared to 8-10 for conventional oil. For me, I’ll spend the extra 22 bucks for peace of mind. They’ve done studies and the two types offer pretty much the same protection up to like 5-6k miles. After that the synthetic holds up better. So if you change your oil regulary you dont have to worry. ---
**Author:** ![neurokinetik](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/neurokinetik/32/7270_2.png) [@neurokinetik](https://forums.speedlife.net/u/neurokinetik)\ **Post date:** [July 24, 2005, 1:57pm UTC](https://forums.speedlife.net/t/oil-discussion/749/22 "2005-07-24T13:57:06Z")
Well, on the advice of some fellow Miata people, I decided to try something completely different for oil: Shell Rotella T, 15W-40. It is designed for diesels, but that doesn’t mean that it is not also good for gasoline engines. I guess the additives that they use are pretty robust, and another guy who had the exact same problem as me said he got to his 3000 mile point without any lifter tick at all using this oil. The best part about it is that is is only a little over $7/gal for dino, and the synthetic version is just over $13/gallon. Sure beats the $20+ for Mobil 1 if it holds up. I’ll report back in about 2800 more miles. So far it held up to the two-driver auto-x test pretty well. No tick at all during startup or after two consecutive hard runs. Oh and if you have a diesel (Tom), this oil is probably a great choice, as it supposedly has some good anti-soot properties. ---
**Author:** ![Ninja](https://avatars.discourse-cdn.com/v4/letter/n/53a042/32.png) [@Ninja](https://forums.speedlife.net/u/Ninja)\ **Post date:** [July 26, 2005, 8:40am UTC](https://forums.speedlife.net/t/oil-discussion/749/23 "2005-07-26T08:40:37Z")
Synthetic I read also has smaller molecules or some shit like that… allowing it to get into smaller places and crevices in your engine. I forget the name of that awesome oil site… with forums and everything dedicated to oil… it was like… [Bobtheoilguy.com](http://Bobtheoilguy.com) … or something. Anyone else remember that? EDIT: found it [http://www.bobistheoilguy.com/](http://www.bobistheoilguy.com/) and I just relized someone already mentioned it above… BITOG ---
**Author:** ![Z24Challenge](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/z24challenge/32/7231_2.png) [@Z24Challenge](https://forums.speedlife.net/u/Z24Challenge)\ **Post date:** [July 26, 2005, 8:44am UTC](https://forums.speedlife.net/t/oil-discussion/749/24 "2005-07-26T08:44:47Z")
> [@Ninja](#): > > Synthetic I read also has smaller molecules or some shit like that… allowing it to get into smaller places and crevices in your engine. > > I forget the name of that awesome oil site… with forums and everything dedicated to oil… it was like… [Bobtheoilguy.com](http://Bobtheoilguy.com) … or something. Anyone else remember that? > > EDIT: found it [http://www.bobistheoilguy.com/](http://www.bobistheoilguy.com/) They sell that oil additive… it has the small molecules or whatever, which they claim seal scratches and shit in your pistons, reducing blowby etc… and increasing power. I forgot what the hell it’s called… I never trust those car product infomercials… but the little animated diagrams were cool. EDIT: this is it: [http://www.duralube.com/index.cfm/&adv=googleads&tar=oilgroup](http://www.duralube.com/index.cfm/&adv=googleads&tar=oilgroup) ---
**Author:** ![Fry](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/fry/32/7284_2.png) [@Fry](https://forums.speedlife.net/u/Fry)\ **Post date:** [July 29, 2005, 12:28pm UTC](https://forums.speedlife.net/t/oil-discussion/749/25 "2005-07-29T12:28:12Z")
Check out [http://themotoroilsite.com/forums/](http://themotoroilsite.com/forums/) for some good reading on oil. The Motor Oil Bible has some pretty in-depth quantitative evaluation of oil brands. Amsoil seems to finish in the top 5, if not first, in every weight. Redline and Mobil 1 are usually all right up there too. I’ve heard that if you switch from petroleum to synthetic on a high mileage motor you might start finding oil leaks in new places. Synthetics have smaller molecules or something, so that they can slip through where thicker petroleum cannot. ---
**Author:** ![slowtalon](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/slowtalon/32/7205_2.png) [@slowtalon](https://forums.speedlife.net/u/slowtalon)\ **Post date:** [July 29, 2005, 1:49pm UTC](https://forums.speedlife.net/t/oil-discussion/749/26 "2005-07-29T13:49:01Z")
> [@BikerFry](#): > > Check out [http://themotoroilsite.com/forums/](http://themotoroilsite.com/forums/) for some good reading on oil. The Motor Oil Bible has some pretty in-depth quantitative evaluation of oil brands. Amsoil seems to finish in the top 5, if not first, in every weight. Redline and Mobil 1 are usually all right up there too. > > I’ve heard that if you switch from petroleum to synthetic on a high mileage motor you might start finding oil leaks in new places. Synthetics have smaller molecules or something, so that they can slip through where thicker petroleum cannot. Synthetic oil molecules are all the same size and shape, while petroleum oils are not uniform and can fill in spots that synthetic will not.its like filling a garbage can with golf balls, there are going to be spots that wont get filled because the balls do not fit together. Now fill the same garbage can with pieces of broken glass the odd shapes will find there way into places kinda like a puzzle. ---
**Author:** ![Jesse](https://avatars.discourse-cdn.com/v4/letter/j/c77e96/32.png) [@Jesse](https://forums.speedlife.net/u/Jesse)\ **Post date:** [July 30, 2005, 6:37pm UTC](https://forums.speedlife.net/t/oil-discussion/749/27 "2005-07-30T18:37:39Z")
i use a semi synthetic 20w50 deisel oil in the summer on my 1988 1.8L turbo engine. and i also used it on my ka24de engine in summer only. now i beat the living shit out of my engine on a daily basis. I bring it up to redline atleast 4 times every time i drive my car. Its daily driven and i used it on both engines. it is a no-name oil i bought from wallmart. majority of deisel engines are turbocharged +1 in canada our gas has high sulphur (sp i cant spell for shits), deisel is high in sulphur. +1 not a full synthetic so the oil isnt gona seep out of my main seal +1 none of my engines have ever burned oil. now i did blow a seal on my turbine on my ca, but that was revving it at 8grand for 1min runs all afternoon. but it also is from an 88 that has 100+km. this was recomended to me by my good friends dad who has been a mechanic for 35 years and who had a 190hp pushrod 1.9L n/a mini hemi. A 73 t327 levin. Who was also a head mechanic at a toyota dealership in the late 80’s and also a mechanic for mazda in early 90’s. my .02$ [Previous page](https://forums.speedlife.net/t/oil-discussion/749.md?page=1)