Just a big ups to all the contributors in this thread,
bloody interesting read

Cheers

sinkas

 

Surely you jest. A liter every 400 miles (640 km)? That's about 8x what I use without a Sohn and stock oil injection, and about 5x more than manuRX8 with a Sohn and increased oil injection.

 

You're right. Like I said, I didn't keep track. I also track the car and have raised injection rate via tune. A track day is a liter all by itself so it's actually not that crazy if you think about it.

 

I can use up to 1.5 qts through my Sohn in 6 x 20 minute sessions at Blackhawk Farms Raceway. This is with OMP output increased via VersaTuner.

 

My understanding is that '60' is the max. travel of the omp and that setting a number higher than that does nothing.

 

I mean, I burnt about 200 mL of oil from just 7 laps of AutoX, each lap is only a minute long.

But I should probably shut up since I have an S2.

 

So what would a map look like for that engine? My understanding is that the injection is from an electromagnetic driven piston delivering a fixed amount of oil per pulse. X number of pulses per second?

 

I don't know what the map would look like exactly.

From the Service Highlights, it looks like it's a combination of the stroke intervals of the plunger/piston and the amount that flows into the OCV.




Either way, I am just saying that 1.5L on for an hour or so of track driving isn't unreasonable for an S1 that has its oil injection rate turned up and a stock S2.

 

Been following this thread since November/December of last year... Honestly, some to most of the information here is still a fair arm's length over my head; but I finally got around to ordering a spare OMP to perform Mod 2 on mine with. I think it turned out well, but I'll see how it works when it's finally installed. I also did mechanically "overclock" the OMP like kevink0000, so I'll see if I did that properly once it's installed.... I'm hoping I won't have to use crankcase oil, but funds will determine if I'm able to get a SOHN or not

Also, pardon the low comment count; I spend most of my time reading and rereading (I really don't like commenting unless I have something worthwhile to say), and besides that most of this last year has been spent trying to save up for a new engine (which is going in either this month or next)

Thanks for all the info; I couldn't have made the mod otherwise

 

My mod is to not plug it in and run heavy premix instead with E85 fuel

 

I'm doing the same (except e85 fuel) my newly rebuilt motor has never had the mop running on it. I'm running strictly pre mix. About 10-12 oz per tank.

 

Me too ... I'm running E30 with Motul Micro 2T at 120:1 . OMP is bolted to front x-member and still connected electrically but not mechanically.

 

I saw where the hardcore alcohol rotary racers in NZ swear by Castrol R30, but down there seems to be the only place that has it

 

Yeah ...apparently it's a thing :

PROCUCT APPLICATION Castrol R30 is for use in competition applications only. It is suitable for crankcase lubrication of four stroke engines when using Methanol or standard fuel. Where Castrol R30 is not being used as the main lubricant it may be used in the fuel at a 1% (100:1) mix in order to obtain the well known racing aroma. Although Castrol R30 has limited solubility in petrol it may be used for two stroke lubrication however, separation may occur if a fuel /oil mixture is left to stand, leading to poor performance and possible engine damage. NB: Engines must not be stored indefinitely with Castrol R30 in the crankcase. Castrol R30 will not mix with conventional mineral or synthetic oils. The recommended flushing procedure must be adhered to when changing oil types. PRODUCT FEATURES & BENEFITS  Has excellent lubrication properties protecting highly stressed engines under severe conditions  Extreme film strength offers a great margin of safety  Imparts an exotic aroma to vehicle exhausts  Suitable when using Methanol fuel or standard petrol

 

I finally have some real-world number for you Brettus. I finally put my reman rotary in and have been loving driving this car again... really missed it

Now, before I get to my numbers, I do have one other mod that may affect the numbers: I have Mazmart’s oil pump mod

When I had my old engine, it would use about a quart every 1k to 1.2k miles depending on how I drove it. Now with my new engine and modded omp, it uses about a quart every 600 miles; cold starts are something to behold

I’m kind of loath to drive it around injecting dirty oil, but I did it just for you Brettus...... now to get my Sohn adapter.....

And yes, I premix. I personally prefer a heavier premix at 1OZ per gallon

 

Nice ... numbers work out pretty close to what you might expect . So you have doubled oil use AND you premix ..... FFFFFFFK!

 

I’ve noticed that when I premix the exhaust smells cleaner; well, maybe not cleaner, but definitely less burnt (yes, I’m cat-less). Now, my father with his S2, when he premixes his actually runs worse and gives him weird issues. Now I don’t have any of those issues even with my heavy premixing, so I’ll keep my heavy premixing

Now, on my to-do list is a sohn adapter, so what do we say here? Sohn adapter and premix...

Anyway, I think I’ve contributed as much as I can on this topic for now. If I have anything else I’ll chime in at that time. For now I’ll keep up and read along, thanks for the mod; it’s made me a lot happier with it’s oil consumption rates

 

A couple months after I had gotten my 8 running, the OMP threw codes (typical after modifying it I know...). Anyway, that problem got fixed. I had to put a "new" OMP on, and I transferred over my modified large piston. I've since put quite a lot of miles on it and I have an observation I just wanted to share;

The oil consumption rate has gone way down since I installed the new OMP without the mechanical overclocking(?). It's made it to where it uses about half as much oil as it used to, and I'm not happy.... With how this engine causes massive oil dilution (I've since gone up to 15w40 and today it finally started draining like 5w30 oil after about 15 hundred miles, where it used to drain like 0w20 after about the same when I was using 5w40), I really preferred having the higher oil consumption rate because it used the diluted solution faster which kept more fresh oil in the system. So, I'm tossing around the idea in my head to modify another OMP (albeit more studiously this time) so I can go back to my seemingly perfect oil consumption rate (at least in my opinion).

Which, with the more diluted oil not being burned as quickly, the car gets a slight shake after about 12 hundred miles (poly motor mounts are great at communicating this). With my previously modified OMP, the car didn't have a slight shake/shudder to it at idle ever. Honestly, it felt and sounded amazing

Now it was kind of funny, with the overclocked OMP, I would always have a chem trail no matter how warmed up the car was. Now, after the car warms up, the blue smoke goes away and I'm wondering if it's healthy for the engine... probably not, since my oil consumption went down 50%

Sorry if I'm beating a dead horse, but I've been meaning to reply for a while

 

I tried to understand what you have going on but you lost me .
Is it
large pistons in omp
Sohn adaptor fitted
premixing at 1oz/gal
and now it's not using much oil ?

 

I felt the same after reading that. It's very interesting to read what other guys are doing for omp setups and I think spartantrap is on to something!

 

Spartan:
Thanks for the post.

If you move the switch around on the modded OMP you can likely get it to stop throwing codes.

My engine as well seems to "enjoy" the increased oil injection. I think the injection delivers more oil better than simply premixing, although I still do both, because the OMP is not 100% effective, just my opinion only. Some will say stock rates and 4oz in the tank is fine. I differ.

However, one caution I might throw at you, if you are using the big piston mod and the overclock mod, the I would only run that much oil with a Sohn. Standard motor oil burns so badly with hard carbon and metallic compound deposits, that you might help one issue but create another. A good quality 2 stroke oil will be smokeless when the engine is warm, even at those rates, and carbon deposits will be several times less.

I like a lot of oil going into my engine, probably more than 99% of owners here, I would get flamed harshly and uselessly if I divulged how much, but I will not use regular motor oil for injection, especially at greatly increased rates.

So next time you change your OMP switch adjustment, or install your old modded one, install a Sohn. I really think it is that important, especially long term.

 

Sorry for the ineffective communication of my thoughts...

Yes, large piston
No, Sohn adapter
Yes, 1oz/gal
Yes and no on oil consumption rates

With my previous OMP that had the "overclock" mod found here: https://www.rx8club.com/series-i-maj...tments-120276/
it used a far more sane(?) amount of oil (read: I actually had to top off my oil every fill up at a gas station). Now with my replacement OMP without the "overclocking", after the "overclocked" on threw codes; without having it "overclocked" I barely have to top of my oil at every fill up. Unless I'm spending over 70% of my drive time either redlining it or full throttle, then I have to top off the oil a little bit more, but no major difference.

Now, I miss those oil consumption rates for two reasons, 1 because with how much oil it consumed, it kept the viscosity higher. Because it was consuming more of the gas/fuel mixture that occurs in the rotary sump. And 2 because it actually used more oil while "cruising" (read: sitting somewhere between 4k and 5k rpm at a steady rate of speed)

I just want my engine to last

Kevin, thanks for the reply

After the overclocked OMP threw codes and put it in limp mode, I tried installing the position sensor in all different manners. I even slotted the plastic so I could get even greater adjustment out of it; nothing worked... thus the replacement OMP. I'm pretty sure it happened because when I was initially overclocking it. I accidentally made the saw blade swing a bit too far, and the teeth on it became disconnected from the potentiometer that the computer reads. I'm pretty certain that's what led to its eventual failure.

I completely agree with you about oil consumption rates; if you could PM me how much 2stroke oil you go through in a month, that'd be wonderful

I'll bump the Sohn adapter up the list, but I'd like to get two OMPs to mod into another overclocked and dual large piston though. That way I can keep my known working one on hand in case I get codes again... Give me a month or so, I'll try and get it done soon and report back

Lastly, sorry for the late reply everyone

 

Well everyone is welcome to their opinion. The truth is there is no real proof that a Sohn is anything more than a feel good device. I understand why people want to believe in it, but some engines with it have a short life while others without don’t ... and vice versa. The results are all over the map and there’s not any real science or correlated methodology to back up using cold xxx injection oil than warm xxx engine oil. For racing or high alcohol fuel you need more pre-mix than the OMP can possibly deliver. The only reason to run under 1 oz per gal premix in gasoline is for cat converter life. If you really want to sustain better sealing you need at least 2 oz. per gal, a lot more than that with E85. When people say they’re not getting full apex seal length coverage the issue is less about distribution and more about not enough oil. Unfortunately from an emissions perspective Mazda’s hands are tied. Even a 3rd nozzle still doesn’t address the issue. They could have 4 per rotor and it still won’t help without upping the volume.

 

Sounds over the top . All the race teams here run 100:1 which is a little more than what I run . I dropped back to 120:1 (approx 1oz/gal) from 100:1 as I found too much premix oil ends up in the sump at high ratios.

 

Can you imagine what 2oz per gallon mixture would do to a catalytic converter, lol. And Maybe the Sohn adapter is a feel good device. I think it's one that I would feel good about installing in one of my 8's. I don't think it can hurt anything.