Project RX-8: SOHN Oil Metering Adapter Install 

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Is Sohn oil injection different from premix oil? Or the oils are injected in different areas of rotary chamber? Thanks

That advice is based on '90s and prior oil tech. Modern synthetics are usually fine, but it depends a bit on the additive package. Some have too much zinc which is bad for cats.

Not a bad thing to throw some premix into the fuel before a lot of hard driving.

I only add a little to the fuel tank if I am going to put it on track where I will be at a sustained high RPM.

@@TheSlipAngle Last Sunday, I picked up a 2009 RX8 R3! Thanks for all the videos on upgrading the RX8's. I live in SUCKY California were we have CARB. So there's not a whole lot I can do to sup up my car. :( So unless you're taking you car to the track, there's no need to premix the fuel after you install the Sohn adapter?

@@TheSlipAngle Quinn , does preMixing at the fuel tank have any negative impact on the fuel filter, fuel pump and or fuel injectors/fueling system ?

The airbox is just in the way of getting access. Premix is meant to be injected into combustion chambers and burns clean. Synthetic engine oil is not and does not burn clean. You can run synthetic engine oil when you get rid if oil metering from the crankcase

@@TheSlipAngle ok. It just confused me since it says it's synthetic premix. I didn't know the difference between the Premix and oil being synthetic. I appreciate it. You didn't drain the oil or radiator correct?

You do not need the SOHN if you premix. It might actually be more work to delete oil metering all together vs running the SOHN. Given that the car is my daily driver, I just wanted the convenience that the SOHN offers vs adding oil into the tank with every fill up. I straight up premix in my RX-7s though.

Love your videos and thank you for your answer.

Because you need the oil injection more for keeping side seal temps down, side seals are the weakest link in the renesis due to the exhaust port location.

While not a huge issue when you're off throttle decelerating the ECU cuts off the fuel injectors, if you only premix and cut off the oil injection your engine wont receive lubrication during that period of time. Now like I said before it isn't a huge issue since the porosity of the metal holds onto some of the lubrication and usually decelerating this way is done for very short periods of time so I haven't heard of any motors using only premix failing from lack of lubrication. A good many race engines only use premixing for lubrication as well and don't seem to suffer from decel fuel cut under race conditions but it's also recommended to use a high ratio of premix to fuel in race conditions. While daily driving however there can be times of extended decel fuel cut, I live in a valley and one of the hills coming into it lasts a good 2 minutes coming down. While I premix only I always put the car in neutral and use my brakes instead of engine braking because the thought of the engine going that long without any internal lubrication doesn't sit well with me. If you use this adapter and premix you can get the best of both worlds knowing that at all times your engine will be receiving lubrication as well as the lubrication coming from dedicated and clean sources specifically for this task.

There is no soon kit for the series 2, we are just SOL there

Does anyone make a block off plate for S2 OMP? That way you can just premix in the tank.

Premix hard may be a temporary solution for you.

@@She1lby I fixed it now. I took the car apart what happened was the plug (Oil Metering Pump Sensor) was broken I dont know how so I just replaced and reset the OMP sensor. Thank you for the advice though I really appreciate it.

@@iamlinxx_ Damn you fixed everything by yourself that's awesome. Btw what oil \ premix do u use?

@@She1lby I had help from a friend and it was a lot of trail and error to be honest. Everyone was telling me you cant replace just the oil metering pump sensor and you need an entirely new oil metering pump but thats like £1400+. As for premix I use Idemitsu (I think thats how you spell it).

@@iamlinxx_ Nice, you just pour it in fuel or is it inside your sohn adapter?

So far so good, but keep in mind the car has been parked for most of the winter. I've put maybe 2k miles on it with the adapter.

How's it going now? Haha. I'm buying an rx8 soon.

Enkei Kojin

LHD

thank u

They have both. Go buy one on ebay bro

225.00 if I remember

I don’t know how you could possibly do that for 20 bucks

Awesome Daniel! I am really glad to hear that!

Thank you James 👍

Modern synthetics are fine. It was back in the '90s and prior when parrifn-based synthetics caused ashy deposits. Most high quality synthetics are ester based and usually burn cleaner than non-synthetic. Examples: Mazda's rotary engine oil sold outside the US is synthetic. As is Idemitsu's Rotary engine oil is 10w30, and what I've run since break in.

@@3toedSloth75 is new synthetic 2 stroke oil ok to premix with fuel from 1/2 to 1 oz per gallon on 04 Rx8? Thanks. I read that regular mineral oil burns better.

@@chrislg4519 I use Idemitsu rotary. It's a blend. Some synthetics are fine to use. Royal Purple is another I've used

@@3toedSloth75 Ok thank you 👍🙏 i may experiment with different premix oils to help preserve seals & compression. So hopefully seals can somehow be better lubed to last longer 🙏⭐ in this video, it seams Apex seals are made of metal. They dont look like rubber, so maybe oil is disbursed in rotary chamber.

I haven't but if there was enough interest I can certainly cook something up. In the meantime, feel free to reach out to me in the meantime if there is anything I can help with.

Thank you!

That is correct!

Just search SOHN RX-8 on ebay. You can buy just the adapter or the adapter and the reservoir kit like I did. I think I paid around 225 bucks total.

No check engine lights from this mod.

They are not nearly as finicky as people make it sound. The flooding thing was only really an issue on early 04-05 models with earlier firmware versions. I can shut the 06 off after moving it a couple feet when cold and it doesn't flood. I don't know what firmware flash it is on, but I would assume it is a later one.

It primarily is caused by the stock ignition system. The start engine is really weak, and is not strong enough to really ignite completely leading to a flooded engine and then you're all sad because you're spark plugs are soaked. Best thing to do to fix it is to upgrade the starter engine to a 2.2kw starter from the stock 2.0kw one as well as make sure you replace your coils when needed. Sometimes I get to work where the needle is below empty and I just have to hope I can make it to the gas station across the street when I get off work (I should start carrying a gas can with me in my trunk, eh?) and I can shut it off cold to put gas in. It has started up every time that's happened, but sometimes it'll lag for about 5-6 seconds and get me really scared because I don't wanna have to deflood the thing in the gas station parking lot >_

Edd Stance Honestly I have a 04 rx8 and as for the flooding issues, never had any. Even if I stall after starting. What I do for a "start up procedure is I let it run untill the idle dies down a little bit. When you first start the car it will idle high and be sending a lot of fuel into the system, but only for a minute after that it should really be fine. And in case anyone asks it's the factory s1 starter lol.

eBay years ago

Enkei Kojin 18x9.5 +30. There is also a video on them and the coilover install back a little :)

Thank you. The SOHN adapter blocks off the oil passage to the engine and pulls premix from only the external reservoir, which is delivered to the housings just like stock.

@@TheSlipAngle thanks for you video. Want to ask if i can use the same oil that i am using already for my engine or to i need to get a especific one? Also just want to make sure when you installed what it does is it gives more oil than the original pump right?

It's the same amount of oil as stock, it's just that it's clean oil and much better of a completed burn than the previous used stock pumped engine oil.

It would inject the same amount per RPM as a factory car.

@@TheSlipAngle Thanks!

That I am not sure about. I just ran premix in the fuel tank in conjunction with adapter and made sure that the oil level in the sohn resevoir was dropping with driving

@TheSlipAngle That's what I'm doing too. I am running heavy until I see that level mark drop. Thank you.

You only have to rev them if you turn it off when cold!

Thanks man 👍

Most people ride a two stroke motorcycle and I've seen them having no problem regularly top up the oil so yeah as long as there is a low oil level light indicator in a cabin there should be no problem.

They had to pass emissions that’s why they designed it the way they did

@@JIMWSMITH noted

You can still throw some premix into the tank if you are going to run a track day or be at sustained high RPM for a while. This prevents oil being pulled from the oil pan and being injected into the motor, which means no more constantly monitoring oil levels and now being able to run full synthetic oil.

This is to prevent injecting hot engine oil as the means for lubricating the apex seals which is more ideal for any situation. If you are going big power or tracking the car, it's a good idea to premix a little in the gas as well.

Thank you! No, I no longer premix in the gas for daily duties, for track stuff I throw .5 oz per gallon in for a little extra jam ;)

The Slip Angle can i ask do you have any recommendations for what 2 stroke oil to use? grade? synthetic/mineral? i live in Australia and don’t have easy access to idemitsu premix, some say any 2 stroke is ok just wanted to ask your thoughts

Can you get Castrol Super Outboard 2 there? I ran that stuff for years with good results up until it became difficult to get in the US.

The Slip Angle there appears to be a Castrol 2T motorcycle oil near me and Castrol outboard 2T oils available but not as close, im guessing either would be ok? the outboard stuff seems cheaper too! but if you think outboard i’m sure i can find a suitable one, thanks again so much for your time and patients 👍🏼👍🏼👍🏼

I only have experience with the Super Outboard 2 stuff so I can't really comment on the motorcycle one. I'd make sure it is combustion chamber safe and meets the same criteria as the Outboard one.

If you still have a Cadillac converter get rid of it

I haven't tried them. I've had good results with the idemitsu so that is why I've just been sticking to it.

I run Royal Purple HPS 10w-30 in the engine for this car.

Yeah, a Koyo is on my list. The car only has 38k miles on it, so I am not really worried about the radiator failing yet.

Coconut

@@devonswindell9735 FUNNY REAL FUNNY

Royal Purple HPS 10w-30. I have deleted Oil Metering.

You can always make your own if you want more capacity.

Yes

I routed mine zip tied next to the rad hose under the battery tray. You may want to try that to keep it farther from the exhaust

Hey Mark, the Sohn adapter is dependent on having a working OMP pump. Do you know where or why yours is not working?

@@TheSlipAngle Not really certain on how it why it isn't working. The only diagnosis or signs that it isn't working is, my car drives poorly and doesn't burn oil anymore. Whatever amount of oil i put in, after 3 months its still the same amount.

Mark did you figure out what the problem was? I'm having the same issue my omp is throwing my rx8 into limp mode and I'm finding stuff on resetting it without replacement . Just curious what route you took?

Hey Frank, I didn't have to cut anything to make this header work. I don't think that is typical for the RX-8. You will most likely have to disconnect the engine mount though to install.

Garage Quinn Motors i understand, I might have bought a cheap header. Thx for info

Yes...still need to cool motor oil

www.rx8club.com/series-i-tech-garage-22/mop-dtc-p1686-dtc-p1687-dtc-p1688-limp-mode-58119/page1/

Holds almost 2 quarts

@@TheSlipAngle so would this be good to do if I don’t premix, I want to, but as of now I still have the stock exhaust.

@@TheSlipAngle also do you still need to do oil changes? Fill your car up with oil? Sorry lots of questions, hard to find answers online.

@@TheSlipAngle I have also looked everywhere and cannot find a full kit online

I change oil when it gets dark and typically that happens between 2-3k miles depending on the car. The RX-8 I still change a little before 3k miles.

why not change it every 2-3k? it's by far the cheapest way to make sure your car doesn't explode!

Royal Purple HP+ 10w30 👍

The series 2 cars received additional oil metering squirters, so in a track situation I would probably premix in addition. Daily driving, I do not premix on top of this.

thanks. From what year is "series 2" ?

2009 - 2012

Jim Smith about every one-two oil changes. You can buy it on eBay for less than 300

The tank holds almost 2 qts of fluid, so you can go a decent amount if you factor in that stock injects about .5 quarts every two tanks of fuel. I like the ease of not having to check the dipstick all the time and just being able to look at the tank to see if I need to add or not. So far it's been working out well.

Jim Smith I never calculated. But I believe the full tank will last at least 3k miles.

I have a sohn, and I fill it up oh every month or more. But I drive my 8 hard. Real hard

I had a bad experience with Braille so I won't ever be using their products again. I have heard a lot of good things about Shorai and am probably going to try them next and for this car to further the weight reduction.

I have used a small agm which only lasted a year. I am thinking about going with a sized miata battery next time. I have been using a penzoil/quicksilver premix from wallmart for 25k miles. Not that it is better but it works well as far as I can tell.

I have used Quicksilver in the past when I needed to grab something quick locally. No issues.

+1 GQM on Braille x 2- failed on different DD project- ECU reset, lost stereo- PITA to fix. Rotaries start 'pig rich' and need lots of juice to spin starter fast- to prevent flooding motor. Since de-flooding 13-B is also a PITA (oil change for the OCD), I'd rather go AGM, maybe even a Optima Red Top 35 R- reversed terminal- and, reduce weight in other ways. Heck, even new, I run a small trickle charger off season, clean grounds and consider swapping ground straps all the time. Since ignition is the motors weak spot- I hate to fool around with anything that might compromise it. I've read mixed bag reviews on Shorai Lithium batteries- not sure if I understand its properties well enough to run with confidence. I have an '08, and, stayed away from '04 & early '05's, so I wouldn't have to worry as much about replacement motors. Maybe overly cautious, but- don't want a pretty paperweight, or, robust boat anchor. Can't afford a re-build on top of: purchase price, mods & running expenses!

4-5 tanks maybe? I don't really keep track lmao

@@TheSlipAngle Ok, so it's not like DEF in diesels, where you have to refill it everytime you refuel the car. (sometimes twice on one tank)

The pump housing seals up the passage way to the engine's oil and prevents it from entering the pump.

Garage Quinn Motors alright thanks

Is that mean the four tiny clear tubes are the pathway for premix to get into the cylinder?

Bob George , so the sohn blocks infeed from the pan. And it feeds new oil from the tank next to w. washer

Good man, you?

No by installing the sohn adapter you're blocking the engine oil and only drawing from the reservoir ..(clean oil) so gotta make sure reservoir stays full... hope that helps...??

@@jakeowens5580 hey! Also can you use the same oil that you are using for your engine or need to get a especific one for the reservoir? Thanks.

@@Jorge-ku1zz I use rotary specific oil. Called Idimitsu racing lube. any good 2 stroke oil will work though. You want something that's ment to burn off clean after it lubricates... I order several quarts of idimitsu off of ebay or amazon fairly cheap. Hope that helps

@@jakeowens5580 yes, i use regular mobil one in my rx8 because i was not sure wich one was better i think i will order idimitsu thank you for your help. What size you think i can use 5w-30?

@@Jorge-ku1zz run the idimitsu rotary premix in sohn reservoir. And mobile one for the engine is good.. I still use 5w20 only cause the Mazda manual says to but alot of people use 5w30 or 10w40..