Black Mamba

Dear all,

I was wondering which Synthetic Engine Oil e.g. Shell Helix Syn etc would be suiatble for use on the rotary engine, as the last I would want is a build up of sludge in the engine...

All comments, replies and snide remarks are appreciated...

KJ238

The famous ones that most people have told me is good is RE Amiya... Trust RE2 oil is pretty good too according to people..

I just use plain old Mobil1 10-40W... Am looking for other alternatives too as the oil is pretty thin after 3000km....

sqflyer

Ermm... isn't Mobil1 synthetic oil? KJ, do you know that rotaries cannot run on normal synthetic oils? You need synthetic oils specially made for rotary engines. The reason why your Mobil1 gets too thin after 3000km is coz it is burning up inside the engine and leaving all it's deposits too.

KJ238

Hmmm.. I believe you are slightly misinformed...

I'm not gonna debate synthetic vs non-synthetics as there is a long one here:
https://www.rx8club.com/series-i-tech-garage-22/cumulative-synthetic-oil-discussion-52856/


Anyways, to continue 10-40 is semi synthetic. 5-50 is fully synthetic.... I have seen a lotta cars that use fully synthetic and the oil does not come out this way. I have read a lot about mobil1 being excellent fuels but not for rotaries thus i am looking at switching.

I wouldnt mind getting a specially made synthetic oil but all of them says NA... And 2ndly there is also the cost factor (not that i really mind)....

I'll probably be switching to Shell for a try the next oil change... Probably fully syn

Goody

just changed the engine oil 2 days ago. the workshop used apexi n1 15w-50 sl partially synthetic oil. 4l in a metal can. they said all the 8 serviced by them used it.

does anyone use it before?

or have any experience to share about this engine oil.

sqflyer

Ok, many views on this issue. I'm just staying with minerals because I don't see any reason at all to go synthetic.

tems900

Have been using Royal Purple 10W30 for e past 2yrs & just switch to redline 10W30 which is more expensive, i think most US 8 is using R.P. or R.L. & seen like racingbeat is recommending R.P. also. If interested in R.P. or R.L. can call terence 90262657 http://www.mxtradings.com/, definitely u can cut down on your 8 maintenance cost, u can buy e OEM 8 oil filter at $6.20 inc. GST.

foo77

^ the price list in the website, is it US or Singapore dollar? Thanks.

Emperor

Royal purple is good. Been using it since my 2nd servicing. Feedback is also good from the other US club members.

Cheap for fully syn. Plus they have said on their website its ok for rotaries.

coupe07

must be ST POWERED... they recommend all their 8s to use apexi oil..

coupe07

like i always said, dun ever try to use any synthetic oil on the rotary engine, no matter how good or how expensive.....

only use synthetic oil meant for the rotary engine. MIneral oil is always the safest choice, HOWEVER, all japanese do not recommend using mineral oil as they do not give u the best performance.

Goody

bingo

they are one of the appointed workshops from my pi and i guess they are probably one of the best

hope they use the correct engine oil for my 8 ......

coupe07

were u the one i saw when our cars were there for dyno testing???

as for oil issue, like i said, its either mineral oil OR synthetic oil meant for the rotary engines. They are your safest bets. You wldnt want to see sludge in ur engine and apex seals without realising u have been using the wrong oil all these while...

Apexi - they are not specialised in rotary engines. So their oil wise, although its for racing use, it may or may not be meant for rotary engine. So long as it doesnt state that its meant for rotary engine, its more or less not suitable, unless its pure mineral oil. As i said in previous posting, i have seen damaged apex seals due to wrong choice of oil for prolonged periods, on an opened FD engine. Its a sight u wldnt want want to see.....

M-ster

I'm usually very skeptical about workshops' "recommendations".... not that i dont trust their advise, but most of the time, i feel that they make the recommendations base more on 'business' rather than wat's really good for your car.

ST, they brings in apexi, thus the more their product moves, the more they can order, the more they order, the bigger bulk discounts they'll get.... (that's want i meant by 'business'). So does the oil / parts really good for your? Your guess is a good as mine....

M-ster

hey tems, which of the 2 do you personally prefers?

tems900

R.P. or R.L. both r as good, only R.L. price is almost double of R.P., so far no problem, i think my 8 compression ratio is still good(apex seal should be intact) as i don't feel any pwr loss as compare to 1st day i get my 8 & i rev my 8 to 9Krpm very often. There quite a lot of comment that the 8 apex seal is much much better the 7 one.

All e price on that web is in S'pore $, just give terence a call, it won't hurt, but definitely it will help on your pocket, why he can sell cheaper becos he don't need much business maintenance cost.

M-ster

Dame, i dont get this. 1 quart of the RP engine oil is almost 1 litre. Thus max i need is about 5 quarts. and that works out to be about $60. And thats like CHEAP! the cheapest rotary oil is trust which is still about $140 for a can of (4 or 5 litre can't remember the exact volume). I know one cant really compare the 'rotary' oil to of the normal engine oil of RP, but that still seems like a good buy..... I can now change it twice as often...

CoupeM

If you use mineral...you can change it 4 times as often. Kekekeke

Goody

i don't think so bro. i was there last fri noon between 1 - 2 pm. saw a few evo there instead.

pls see my pm.

Goody

totally agree with you bro. different workshops carry different brand(s) / type(s) of products. the best i think is to get the oil you prefer and get a good workshop to change. just pay the labour costs.

coupe07

however take note that mineral oil will not give u the best performance..... but for the price, its well value for money.

Goody

trying to send you a pm but received the below message:

The following errors occurred when this message was submitted:

coupe07 has exceeded their stored private messages quota and can not accept further messages until they clear some space.

sqflyer

To be honest, I haven't seen anything that says using synthetic oils will yield higher performance than using mineral oils. The "racing teams use synthetic oils so must be better" theory doesn't cut it for me either because 1) I'm not racing 2) race cars have very different operating requirements than the everyday car 3) race cars operate in very different environments than the everday car 4) race teams have racing budgets which includes rebuilding engines, etc. compared to the everyday owner. Basically to me, I still don't see any compelling reason to switch from mineral to synthetic.

Emperor

You are the g-tech specialist. Why don't you try out good syns and measure it against a mineral oil. And make sure you fully flush the oil first.

I have seen dynos of syn vs mineral. Age old question. There was certainly a power gain. A syn oil is made from scratch and formulated for its intended purpose. Compare this to a mineral which is raw oil purifed. Which logically should perform its intended purpose better?

If mineral was as good as syn; why do companies need to spend more time and effort. Couldn't they simply sell mineral oil or additive added mineral oil?

sqflyer

I don't mind doing a g-tech test at all, but it won't produce useful results unless the test is conducted one oil after another which essentially means wasting new old right after the 1st test and replacing with the 2nd oil.

I haven't seen anything to prove there is power gains from different oils (must be same viscosity of coz). If you have any source of info such as dyno charts, etc. pls hook me up.

There could be a host of reasons why companies created synthetic oil, but what's the point of speculating. If I wanted to guess, then I didn't need to ask in the first place. I would have taken everything everyone told me as bible truth and put my tooth under my pillow. Anyway, synthetic may be the best thing since sliced bread for normal pistons, but may not necessarily be the best thing for rotaries. Ahh... the thirst for knowledge.