organicrx8

Indeed. That is comforting.

organicrx8

Per your comment on 2 maps: Those would apply to the omp operation would it not? If there is no omp and the engine relies only on premix would that programming still apply?

UnknownJinX

I mean why get rid of OMP if there is Sohn adapter?

I also believe the 8 injects a little bit of fuel even when engine braking. I have a bluetooth OBD2 that can read/guess instant fuel consumption. I believe someone else also confirmed this.

organicrx8

I use the recommended Mazda rx8 oil in the crankcase; the 2 stroke Still is a minimal premix in the gas tank, so there is 2 oil sources, but the premix is almost negligible.

ChaosReaper

And this is the Premix I use that they suggested. I started with idimitzu or w.e. it's call but they said there no point on wasting alot of money when it's does the same thing. That stuff like the above will do the job
Also heard from a rotary specialist that premix is good since you don't get oil on idle so having the premix ensures that u always have lubricant. Was suggested by them a 1:1 ratio so one once to every gallon. So when I add 8 gallons I add 8 oz. My rx8 has been running for the past 2 years with no problems. Have been doing the Redlines and reg oil changes as well. I still have the brand new sohn John unopened in it's original packaging it came in 2 years ago. I'm definitely not going to install it since it is not a good idea to install it from what the specialists say

Loki

iTrader: (1)

Never speak to this "specialist" again. That's TCW3 oil, it's not doing any actual lubricating because it's not rated for rotary temperatures.

I don't know what Stihl oil rates, but you're looking for FC/FD certification. There are plenty affordable options that aren't Idemitsu.

Neither chainsaws nor seadoos have catalytic converters, nor high compression rotaries. Just because an oil works there doesn't mean it works here in long term.

UnknownJinX

I use Idemitsu. Yeah, it's pricey, but I don't see anything that great being sold near me anyway. May as well buy a big case and be settled for a year.

Also, 1 ounce per gallon is a bit too much unless you track or run without OMP. Premix can lower octane a bit so you don't want too much for DD. Half an ounce per gallon will be fine. That's how I have always done it for the last 2 years.

There are some talks about Sohn adapter not delivering enough oil under track conditions, but for DD it's sufficient. I didn't dig that much into it because I have an S2.

wannawankel

STIHL has always been JASO FC then now FD rated 2-stroke oil. I have never figured out who has been supplying them the 2-stroke oil but nonetheless it is of good quality. To second others comments, TCW3 oil is not to be used for any purpose other than 2-stroke watercraft engines period.

organicrx8

I decided to use the Stihll 2 stroke oil as it is convenient. It comes in either 50 ml or 100ml bottles so I use the 50ml bottle when I fill up and at a full 60 litres that would be 600:1. As the tank is never fully empty the 50ml I use can be anywhere from 600:1 to whatever the ratio is if I fill up with 40 litres. I also would have no hesitation in using Echo 2 stroke oil or Husquevarna but those dealers are not near me.

Realizing the infinite variety of opinions on this issue' it would seem that what is best is entirely personal, and practical if it works reliably; but any oil used must meet the minimum temperature requirements. Typically my OBD2 sensor says the EGT is about 1600F at cruise. I don't know what the EGT is on a chainsaw but you can bet it works hard and flat out all the time; a chainsaw engine life is about 350-400 hours. On a heavy duty turbocharged diesel tractor engine the EGT ran at 1300-1400F.

My reason for using this minor premix ratio is to add a bit of insurance (not much as I didn't want the CAT affected) and as I indicated I would never disable the factory oil delivery system. The dealer put 5w30 Mazda oil in on the last February oil change. The reason I mentioned the earlier 2 stroke Saab engine was the potential damage on high RPM with closed throttle using only a premix lubrication system.

UnknownJinX

50 mL in 60 L of gas translates to 1:1200. Even in 50 L of gas it's only 1:1000. At that point I doubt premix makes any difference.

I dump in 200~220 mL every time I fill up about 50~55 L of gas at the mentioned 1:250 ratio.

organicrx8

And I thought I was reasonably good at fun with numbers. You are dead right; 1200 to one is of negligible importance. From now on its 100ml per fill up. Thanks.

Steve Dallas

If this is available in your area, it is usually reasonably priced and works well. It is what I have used since 2012 with good results.

UnknownJinX

Good to know.

How much do you add for each tank?

Steve Dallas

~8oz per tank on the street and double that on the track.

ChaosReaper

So half an oz for every gallon and you had no issues since 2012? I'm definitely switching to that one since I can order that on Amazon

Steve Dallas

All fuel maps do this. Fueling is done by load and RPM. At very low loads (foot off the gas), less fuel is injected, but the fuel system does not go completely lean. An AFR of around 16.0 is typical, however I have seen my 8 go as lean as 22.0 at no load (put it in neutral at high RPM and let it fall to idle). When engine braking, there is actually a decent amount of load at some RPM above 0, which means the AFR will typically be somewhere between 15.4 and 12.5, depending upon said load and RPM. An engine is an air pump that is always sucking in O2 as long as it is running. It needs matching fuel to keep it running, so it is always fueling to some degree when running.

Here is a generic target AFR table I let Tuner Studio create for my Miata's engine. (The actual table I run is quite a bit leaner all over.) The bottom row is the no load (foot off the pedal) area, which the software defaults to stoich or a little leaner.




Here is an actual volumetric efficiency table I ran for a while during the tuning process. Look at the bottom row again. See how much leaner it is than the other rows? It is richer at higher RPM due to the potential danger there. It goes leaner in the middle to save fuel, then goes richer at lower RPM to smoothly slide into idle fueling without stalling due to being too lean. On that row only, I deviated from the target AFR table to save fuel, because there is little chance of detonation in the middle of that row. The rest of the VE table is tuned to closely match the target AFR table.



The point is, there is always fuel being supplied to a running engine. There are no zeros in the fuel map.

ShellDude

iTrader: (12)

so um, why are we trying to bypass the OMP again?

nordicgreenrx805

Hi, do I have to use the same 2 stroke oil in my Sohn Adapter and what I mix in with the gas?

Im currently am using Ams Oil in my Sohn adapter and nevered premixed. I recently just bought the car. The old owner never told me about premixing.

Loki

iTrader: (1)

You don't HAVE to, but there's no reason to use different oils.
Look for the JASO FD certification on your choice of 2-stroke oil.

NotAPreppie

JASO FD is also identical to ISO-L-EGD (sometimes just ISO GD or ISO EGD).
https://www.motor-talk.de/forum/akti...hmentId=683876

API TC will also work but the additive package may have metals. Incombustible metals + carbon = ash. Also, the metals may act as a catalyst poison and result in a P0420 after prolonged use (though probably won't do anything to the structure of the catalyst bed).

nordicgreenrx805

I’m currently using Ams Oil intercepter 2 strike oil. Is that ok or should I switch to a different one?

wannawankel

Use any JASO rated FD (or JASO FC) premix (2-cycle oil). I buy the cheapest JASO FD rated 2 stroke oil I can find. Menards had a great deal on Citgo Mystic JASO FD rated oil for $16.99 per large bottle (I think it was 5 L).

NotAPreppie

Dude. It's right there, two posts up. If it doesn't say which specs it conforms to, contact the mfr. If they don't say it conforms to those specs, don't use it.

wannawankel

...just do not use TCW3 (TCW-3) rated 2-cycle oils...ever...

TeamRX8

iTrader: (25)

People claim they got “good results”, but then later needed an engine replaced under 50,000 miles ...