RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   New Member RX-7 Technical (https://www.rx7club.com/new-member-rx-7-technical-256/)
-   -   Engine Oil (https://www.rx7club.com/new-member-rx-7-technical-256/engine-oil-1105390/)

prodrive8 09-14-16 07:45 AM

Engine Oil
 
What the opinion on using original factory spec period oil or modern day equivalents?

misterstyx69 09-14-16 07:52 AM

No offense,
You'd be best to research that area of info yourself and decide on what you will use.
There are more OIL DEBATE threads than the grains of sand in the Sahara and frankly none of them actually come to a conclusion.

FührerTüner 09-14-16 07:54 AM

I was gonna direct him to the post count threads but i cant find them.

prodrive8 09-14-16 08:41 AM

That's my point the searches on here are hard work and as with many forums the longer they operate the more difficult it is to find good solid opinion.

I know what oil I use but I'd like to know what others use?

Sgtblue 09-14-16 08:55 AM

I have turbochargers. Turbochargers create an extreme enviroment with lots of heat. Synthetic oil has much better shear properties and tolerates high heat way better than traditional oil. That reduces coking in the turbochargers and their oil supply and return lines. My car still has the original turbos with 128k miles that don't smoke and function as designed. YRMV. My .02

prodrive8 09-14-16 09:17 AM

Is that on an original engine as well?

Sgtblue 09-14-16 09:30 AM

^Original engine rebuilt @ ~ 90k for a coolant seal failure. E shaft and rotor bearings, and oil control rings had typical unremarkable wear. They were w/in spec but were replaced anyway.

Turbo2 87 09-14-16 09:41 AM

I've been using Valvoline Vr1 20w50 high zinc. Been working good for me.

Evil Aviator 09-14-16 07:51 PM


Originally Posted by prodrive8 (Post 12106529)
What the opinion on using original factory spec period oil or modern day equivalents?

The original factory API spec oils are obsolete. That makes your choice a lot easier. :)


Originally Posted by Sgtblue (Post 12106555)
That reduces coking in the turbochargers and their oil supply and return lines. My car still has the original turbos with 128k miles that don't smoke and function as designed.

All RX-7s were produced with water-cooled bearings which reduce coking. There are many RX-7s with over 200k miles on the turbos that don't smoke and function as designed even though the owner used regular mineral oil. Synthetic oil will not make a significant difference unless the car is operated under extreme conditions or if the original turbo(s) were replaced with a cheapie dry bearing turbo. If you do feel a need for synthetic oil, be sure to do your homework as many of them are not truly synthetic.

ForginGeorge 09-15-16 12:34 AM

Castrol GTX 20w50. Non-Synth. The white bottles you can pick up at any auto parts store for reasonably cheap.

misterstyx69 09-15-16 12:39 AM

..N/A Fc..any kind of oil that is cheap and on sale.

RYZ 09-15-16 04:51 AM


Originally Posted by Sgtblue (Post 12106555)
I have turbochargers. Turbochargers create an extreme enviroment with lots of heat. Synthetic oil has much better shear properties and tolerates high heat way better than traditional oil. That reduces coking in the turbochargers and their oil supply and return lines. My car still has the original turbos with 128k miles that don't smoke and function as designed. YRMV. My .02




______________________________
So was the full synthetic oil or semi synthetic? and what grade

Sgtblue 09-15-16 06:57 AM


Originally Posted by Evil Aviator (Post 12106771)
...All RX-7s were produced with water-cooled bearings which reduce coking.

Reduce, yes. But coking can still can be an issue. And I believe synthetic reduces it further. But that's not the only reason to use it...IMO.

Originally Posted by Evil Aviator (Post 12106771)
...
There are many RX-7s with over 200k miles on the turbos that don't smoke and function as designed even though the owner used regular mineral oil.

And probably many many more that that have failed well before then. But you're right, my experience is anecdotal.


Originally Posted by Evil Aviator (Post 12106771)
...
Synthetic oil will not make a significant difference unless the car is operated under extreme conditions

I believe turbo chargers are an extreme condition in a relative sense. If my car was N/A I wouldn't bother with synthetic.

Originally Posted by Evil Aviator (Post 12106771)
...If you do feel a need for synthetic oil, be sure to do your homework as many of them are not truly synthetic.

Feeling the need. This is after all, the fun car. And switched to, IIRC, a group IV not all that long ago.

cmurphy 09-20-16 04:13 AM


Originally Posted by prodrive8 (Post 12106550)
That's my point the searches on here are hard work and as with many forums the longer they operate the more difficult it is to find good solid opinion.

I know what oil I use but I'd like to know what others use?


I'm also in the same situation where i'm trying to find as much relevant information as I can. I use google and filter on this site (e.g. vacuum guide site:rx7club.com) , and it generally finds good information.

cmurphy 09-20-16 04:24 AM


Originally Posted by Sgtblue (Post 12106863)
Feeling the need. This is after all, the fun car. And switched to, IIRC, a group IV not all that long ago.

Which group iv brand and viscosity did you switch to?

sandy_RE 09-20-16 07:06 AM

Penrite HPR 30 is what some of us here in Australia use on our n/a's.

jdeck 09-21-16 01:20 PM

Has anyone ever used Shell Rotella T6 with rotary turbo applications? That's always been my go to for non rotary engines.

TwerkItOnMars 09-21-16 02:18 PM

I think Castrol GTX 20-50 (white bottle) is the best conventional to use. I wouldn't use synthetic stuff unless I had just finished breaking in a freshly rebuilt motor.

It all comes down to personal preference and previous experience for oil, I think.

WI.93fd3s 09-21-16 07:39 PM

I suggest only conventional!!! I use gtx, also change oil and plugs 2-3k!!!!!!

Evil Aviator 09-22-16 12:11 AM


Originally Posted by TwerkItOnMars (Post 12108782)
I wouldn't use synthetic stuff unless I had just finished breaking in a freshly rebuilt motor.

Most racers break-in a new engine with non-synthetic, and then switch to a synthetic after break-in.


Originally Posted by jdeck (Post 12108765)
Has anyone ever used Shell Rotella T6 with rotary turbo applications? That's always been my go to for non rotary engines.

Rotella T6 is not actually synthetic oil. Common real synthetic oil brands used by Americans on this forum include Amsoil, Idemitsu, Red Line, and Royal Purple brands.


Originally Posted by WI.93fd3s (Post 12108882)
I suggest only conventional!!! I use gtx, also change oil and plugs 2-3k!!!!!!

I also use GTX, and it's good for 3-5k miles on the street. If your plugs don't last at least 10k miles then there is something very wrong with your engine or you are using the wrong plugs.

FührerTüner 09-22-16 08:23 AM

FYI you can get a case of (6) quarts of RP 20w50 on amazon for 53 bucks prime.

Sgtblue 09-22-16 08:35 AM


Originally Posted by WI.93fd3s (Post 12108882)
I suggest only conventional!!! I use gtx, also change oil and plugs 2-3k!!!!!!

Must mean you're serious with all the exclamations. But agree with Aviator...that's WAY too often on plugs with a properly running engine.

lOOkatme 09-22-16 10:43 AM

I have run a couple of different weights of oil and mineral and synthetic in the rx7. Yes I fell into the hype at first.

This is what I found out over time.

I went with the recommended weight of 10W-30 and 20W-50 in the summer. the 20w-50 seemed too thick (the car had to warm up some to idle smoother and oil pressures were very high) so I was switching between 15W-50 synthetic (summer) and 10W-30 (winterish).

After a lot more research and combining my own logic I ended up running a synthetic 5W-30 oil and this is what I will be running for the rest of my life in my rx7.

Viscosity of the oil depends on the temperature of the oil, and lower temps need thinner oils, once the car reaches operating temp for the oil you want the pressure to be 60-70PSI to redline, you choose the thinnest viscosity oil that can get you there. thinner is better in terms of cooling the engine and bearing protection (higher flow). I am running low pressure drop 25 row oil coolers ducted and the temps stay very cool for my engine as its a street car. Most wear comes from cold start and that is why I chose the 5W-30 oil (thinner at colder temps). I chose synthetic oil as rotaries run a little hotter and we have turbo's and such. Synthetics are made to this exact spec and mineral oils "dope" additives to make the oil behave a certain way with temp, over time those additives reduce and the oil becomes more of a straight weight, quicker if they see higher loads.

BW also recommends synthetics, as they keep their properties. I am running 2 cycle through the oil metering pump so I am not injecting anything into the engine.

I had dug into oil filters as well. I chose denso oil filters for the flow over filtration. there is a big debate about this but I say flow is more important than filtration. Honda oil filters flow well. so They also agree with the flow category. Bosch Premium filters are probably the best bang for the buck for filtration and flow as they are in the middle of the road for flow and filter very well and what I run on my regular daily driven cars which are Honda's.

Aaron Cake 09-24-16 10:37 AM

I buy whatever 20W-50 oil is on sale and have for the 17 years I've owned the car.

Also I use Fram filters to annoy people on the Internet.

WondrousBread 09-24-16 10:32 PM

If we're talking about filters too, what exactly is wrong with Fram?

I am currently using a Fram and it seems okay. I have an extra one too, but it says that it has some kind of a "high mileage engine" additive in it, and I haven't any interest putting that into my oil without knowing exactly what it does.

Castrol GTX by the way, only because it is cheap and available anywhere. Synthetic might be better, I wouldn't know because there aren't any high-quality ones sold near me so I haven't tried it.


All times are GMT -5. The time now is 10:18 PM.


© 2024 MH Sub I, LLC dba Internet Brands