Hmmm...Redline oil prices vary. They're not cheap. My area sells them for about $6.00 a quart.
If you have the oil metering pump, you might consider non synthetic. Synthetics don't burn like conventional oil. But, to each his own. I've used synthetic while the OMP was attached and it left some sticky film all over the rotors.
Cost is a factor as well. The car will burn a quart or so every 1000 miles depending on how much you mash the pedal. Oil debate could go on and on and on.
My suggestion (just a sensible idea, not an expert by any means) is if you are running OMP, use the lowest ash content / pour point conventional oil you can find.

 

I've got an oil pressure meter, if that's what you mean?? It's not hooked up, but I'm gonna do it pretty soon...

 

No , oil metering pump (OMP) is what injects oil into your combustion chamber depending on the amount of pedal feedback. S4 (86-88) has a mechanical OMP, S5(89-91) is monitored by the ECU (can't be disconnected).
I assume you still have the OMP. If it doesn't get extremely hot there and you don't run your car hard all the time, 10W30 is fine. You can't really get away with high ash content with conventional oil . If you want to use synthetic, it's up to you.
Try to stay away with the wide viscosity range like 5W40, 5W50, 5W30 etc.

 

Hum 2 gears and 4 big bearing. If gear oil is cheap I would run that. SPZ50 let go due to his inproper front cover gasket and O ring deal, well he told me it had low pressure ( 30psi max) and he babied it home for 10 mi or so. Well I said it should be ok as long as you babied it. Well all the bearings were done and it sounded like a diesel when he fired it up. I don't know why but I asked he what weight oil and he told me 10-30W and I just laughed. Light weight oil is only good for milage, and in my opinion trans oil is the same. I put 85-140 in my FD's trans and diff. But the milage dropped 2 mpg so I put Red line Extreme shock stuff in the diff. and left the 85-140 in the trans. and the milage was the same as before. The diff. does not run that hot unless you are doing phat tech runs so heavy oil has a lot of drag on it, and Torsen slosh a lot of oil too. The trans. gets hot enough it thins it ok pretty quick once it is warmed up.

 

Yeah, I have an S5 so it's monitored by the ECU...

If everyone is saying to use non-synthetic, that's what I'll do considering that I don't know much about this stuff...
I am a fuel conserving kind of guy, so I might use 10w30, but I might go to a few AutoXs -- maybe 1 or 2, but it should be fine I think... right?

 

10W30 *quality* oil is fine. Like it says , viscosity breakdown is at a minimum when you stay within a short range such as 10W30. If you are going autocrossing, you should change to a thicker oil such as 20W50.
Lightweight oil is not just for better gas mileage . You need it for winter. It also has quick lubricating due to low pour point. The guy who said 10W30 is for only better gas mileage and thinks the bearings failed because of it? I highly doubt it's the oil he used. He must had some mechanical problems, never changed oil, cheap oil and viscosity broke down, clogged oil jets in the E shaft, etc. When I bought FC brand new in 1986, I religously stuck with 10W30 Valvoline ( before I found the oil site) and changed oil every 4000 or so miles. It never had a problem for 3 years.

 

That would only be in the case of crappy oil company brand synthetics.

The better quality synthetics such as Redline, Neo, Amsoil, Royal Purple, Mobil1 all have a simular flash piont to conventional oils and in each one a lower ash level, than most conventional oils.

Its the crappy synth oils like Valvoline or Havoline or even Castrol Syntec that shoule be avoided in a rotary engine as they will leave increased ash and have strange burn points.

 

I agree. Quality oil should always be used.

 

Am I the only one here that uses Royal Purple? i use 20W-50. maybe im the only one running Royal Purple cause i find it helpful with my piston engine i have.

 

Here's your Royal Purple



Brand VI Flash Pour %ash %zinc
20W-50

AMSOIL(new) 155 474 -47 <.05 ---
Castrol GTX 122 440 -15 .85 .12
Exxon High Performance 119 419 -13 .70 .11
Havoline Formula 3 125 465 -30 1.0 ---
Kendall GT-1 129 390 -25 1.0 .16
Pennzoil GT Perf. 120 460 -10 .90 ---
Quaker State Dlx. 155 430 -25 .90 ---
Red Line 164 503 -49 --- ---
Royal Purple 138 435 -44 --- --- **
Shell Truck Guard 130 450 -15 1.0 .15
Spectro Golden 4 174 440 -35 --- .15
Spectro Golden M.G. 174 440 -35 --- .13
Unocal 121 432 -11 .74 .12
Valvoline All Climate 125 430 -10 1.0 .11
Valvoline Turbo 140 440 -10 .99 .13
Valvoline Race 140 425 -10 1.2 .20
Valvoline Synthetic 146 465 -40 <1.5 .12

Brand VI Flash Pour %ash %zinc
20W-40

AMSOIL 124 500 -49 --- ---
Castrol Multi-Grade 110 440 -15 .85 .12
Quaker State 121 415 -15 .90 ---

Brand VI Flash Pour %ash %zinc
15W-50

Chevron 204 415 -18 .96 .11
Mobil 1 180 430 -55 --- ---
Mystic JT8 144 420 -20 1.7 .15
Red Line 166 503 -49 --- ---

Brand VI Flash Pour %ash %zinc
5W-50

Castrol Syntec 180 437 -45 1.2 ---
Quaker State Synquest 173 457 -76 --- ---
Quaker State Prem.Syn 177 435 -35 --- --- **
Pennzoil Performax 176 --- -69 --- ---

Brand VI Flash Pour %ash %zinc
5W-40

Havoline 170 450 -40 1.4 ---

Brand VI Flash Pour %ash %zinc
5W-30 Heavy Duty Diesel

AMSOIL 170 460 -60 <.05 ---




Brand VI Flash Pour %ash %zinc
15W-40

AMSOIL(new) 157 446 -49 <.05 ---
Castrol 134 415 -15 1.3 .14
Chevron Delo 400 136 421 -27 1.0 ---
Exxon XD3 --- 417 -11 .90 .14
Exxon XD3 Extra 135 399 -11 .95 .13
Kendall GT-1 135 410 -25 1.0 .16
Mobil 1 Super Syn (NEW) 155 491 -49 --- --- ** (Auctually 15W 50)
Mystic JT8 142 440 -20 1.7 .15
Red Line 155 495 -40 --- ---
Royal Purple 149 400 -49 --- --- ** (Auctually 10W 40)
Shell Rotella w/XLA 146 410 -25 1.0 .13
Valvoline All Fleet 140 --- -10 1.0 .15
Valvoline Turbo 140 420 -10 .99 .13



Brand VI Flash Pour %ash %zinc
10W-30

AMSOIL 171 464 -54 <.05 ---
AMSOIL XL-7500 148 471 -54 <.05 ---
Castrol GTX 140 415 -33 .85 .12
Castrol Syntec 157 455 -54 --- .10
Chevron Supreme 150 401 -26 .96 .11
Exxon Superflo Hi Perf 135 392 -22 .70 .11
Exxon Superflo Supreme 133 400 -31 .85 .13
Havoline Formula 3 139 430 -30 1.0 ---
Kendall GT-1 139 390 -25 1.0 .16
Mobil 1 --- 430 -60 --- ---
Mobil 1 Super Syn.(NEW) 145 455 -49 --- --- **
Pennzoil PLZ Turbo 140 410 -27 1.0 ---
Quaker State 156 410 -30 .90 ---
Quaker State Prem Syn 148 440 -40 --- --- **
Red Line 150 475 -40 --- ---
Royal Purple 148 400 -49 --- --- **
Shell Fire and Ice 155 410 -35 .90 .12
Shell Super 2000 155 410 -35 1.0 .13
Shell Truck Guard 155 405 -35 1.0 .15
Spectro Golden M.G. 175 405 -40 --- ---
Unocal Super 153 428 -33 .92 .12
Valvoline All Climate 130 410 -26 1.0 .11
Valvoline Turbo 135 410 -26 .99 .13
Valvoline Race 130 410 -26 1.2 .20
Valvoline Synthetic 140 450 -40 <1.5 .12



Brand VI Flash Pour %ash %zinc
5W-30

AMSOIL 186 478 -60 <.05 ---
AMSOIL XL-7500 160 464 -60 <.05 ---
Castrol GTX 156 400 -35 .80 .12
Chevron Supreme 202? 354 -46 .96 .11
Chevron Supreme Synth. 165 446 -72 1.1 .12
Exxon Superflow HP 148 392 -22 .70 .11
Havoline Formula 3 158 420 -40 1.0 ---
Mobil 1 150 430 -65 --- ---
Mobil 1 Super Syn (NEW) 169 455 -54 --- --- **
Mystic JT8 161 390 -25 .95 .10
Quaker State 165 405 -35 .9 ---
Quaker State Prem Syn 151 440 -49 --- --- **
Red Line 165 455 -49 --- ---
Royal Purple 160 395 -44 --- --- **
Shell Fire and Ice 167 405 -35 .9 .12
Unocal 151 414 -33 .81 .12
Valvoline All Climate 135 405 -40 1.0 .11
Valvoline Turbo 158 405 -40 .99 .13
Valvoline Synthetic 160 435 -40 <1.5 .12



Brand VI Flash Pour %ash %zinc
0W-30

AMSOIL 188 460 -76 --- ---
Mobil 1 175 460 -65 --- ---
Mobil 1 Super Syn (NEW) 176 450 -65 --- --- **
royal purple

 

where have i gone wrong here?
i use penrite 40 (it's aussie)
which is 25-70W

all the rotor shops here use the same, something to do with glazing the seals? heck if i know!

 

Damn, that's some thick *** oil! 25W70 is over doing it. 20W50 is more than sufficient even for extreme hot climates.

 

Anybody try that Marvel Magic Mystery Oil? Heard it does some wonderful *****!

 

I used HD-30 oil. I use Mobil 1 10-30 now

 

i havent read all 6 pages of this thread, but my input is i use 20w50 all year long. my two brothers and i have had 4rx7's altogether and thats all weve ever used. 86 base had 200k miles when sold still ran good, 87 base sold with 127k...as perfect as compression could be w/ that high of milage, 91 vert had 150k before it wore its motor out...however im 100% sure that the carbon buildup killed that motor since my bro never drove it hard at all(auto tranny too). then my 91 coupe has 125k with good compression. i run mmo oil these days as well engine only gets stronger with age haha

 

but what the ****! For the first 3 to 4 pages it was pretty much a bickering match between brockvert7 (or whaetever) and icemark. I saw it as this dude trying to take over icemarks **** and icemark slowly but cooley handlin da bizness.... i luv da izm!!!!! anyway
Im in canada, cars stored in heated garage for wintar. ive been running 20w50 for the spring summer early fall times. is this cool. thats all i want to know. dont want to see another 4 page power struggle. you guys talk about scientific tests on pm ( actually no.. its interesting but until someone wins the disagreements.... my engine is blowing up here!!!!!! ) you know what im sayin....
just tell me what ur using and what i should use for my climate..... ya dig?????