I\'ve done a bit of searching on the forum, but can\'t find that much info to be honest.
Read of people removing the OMP all together and running pre-mix. (what is pre-mix)
What are the benefits of this and are there any negatives?
Also curious as to where you would get a blanking plate for where the OMP was.
Again, what do you do with the nozzles on the top of the engine? Just blank them off with a bit of vac line and a bolt?
thanks in advance!
Premix is when you put 2 stroke oil in with your petrol in your petrol tank, most people add 100:1 to 125:1 depending on power levels. 100:1 means for example you put in 500ml of two stoke oil in with 50 litres of fuel. You put the oil in first into the tank then the fuel to ensure its mixed correctly.
Benefits are you can get rid of the OMP and the risk of it failing.
Even coating of the seals instead of the central part of the apex seals.
Safer on high powered Rotary as you guaranteed proper oil lube on apex seals
Negatives
You HAVE to remember to add the oil into your fuel tank on fill ups.
You will have the addtional cost of buying two stroke.
You may need to change the oil more often as you may have more oil in the sump then when you first had from the last oil change (depends on porting) .
Quote(what is pre-mix)
Pre-mix is adding a good premix oil to the petrol in the tank, i use Millars
KB2T, At a ratio of 1/2 a litre to a Full tank of petrol, or 100 to 1 or some guys 150 to 1.
K.BAREHAM did a write up on replacing OMP some time ago, worth a search,
Bob
Mark, can you explain the below again??? im confused!
"You may need to change the oil more often as you may have more oil in the sump then when you first had from the last oil change (depends on porting) ."
well with OMP the ecu can control how much oil to inject so on cruise hardly any oil gets injected so the right amount gets burned off. with premix you will get more oil then normally is required and not all off it gets used or burned off and gets returned into the sump, every oil change I do I end up with 1/2 litre more then when I started.
The more ported the motor you get overlap so you get wasted fuel mixture and some of that goes into your oil hence you get fuel in your oil. But this seems to affect only heavly ported engines. You can smell the fuel in the oil when you do the oil change
Arh i see! yep mine oil stinks of petrol!!!
yep I change mine every 1000 miles hence the reason why I use normal Castrol or Shell Helix for my oil change no point putting something expensive to get it diluted by fuel overtime
thats what i use shell helix! what afr do you run at idle? 10/11\'s?
well after doing some more research on heavy ported engines be it big street ports or bridge, you get dodgy readings, you may see afrs of 11 but this reading has been containminated by the unburnt fuel and overlap, you true afr may be 12-13.
Hence last year when I saw on my wideband my idle was 11 I tried to lean out and the engine didnt like it felt weak and wanted to cut out, so I put the fuel back in until it gave a good idle again with a AFR reading of 11.5
anyway jim goin back to your question. I used 1 exhaust stud cut it in half ground a slot in the top of each and screwed it into the oil jet hole.
worked a treat!!
also you can get omp blanking plates from Reworx
or just make one.
as you know mark, im planning on running both, is there any disadvantages to this or may cause problems??
I run both but run a 200:1 mix really just to provide a fine coating in addition to the OMP, and shouldn\'t be as catastrophic if the OMP did decide to fail, thats my thoughts anyway lol
Quote from: karl_tate;582857or just make one.
as you know mark, im planning on running both, is there any disadvantages to this or may cause problems??
Yes you would have to have a ratio of 200:1 or 250:1 if running both, the main disadvantage it can lower the octane of your fuel when running both
I\'m running the PCV OMP adapter with separate oil tank. Allows me to feed pure and clean 2 stroke oil (which is meant to lubricate and burn) and the OMP still regulates the amoint that is being injected.
Works well..
You can also in the Apexi ECU increase the amount of oil the OMP injects as well.
Some ECUs will not have this function or some ECUs you have to program an output to do control the OMP
Quote from: BlitzBoy;583089You can also in the Apexi ECU increase the amount of oil the OMP injects as well.
Some ECUs will not have this function or some ECUs you have to program an output to do control the OMP
I assume you have to do this with the Datalogic and the options not there in the commander?
Yes with the datalogit only
What happens if you use normal 10/40 shell oil instead of 2 stroke :2eek
2 stroke is used due to the way it burns and lubricates well, it burns cleanly whereas normal oil will carbonise quite quickly, i believe....
Quote from: Speedworks;583085I\'m running the PCV OMP adapter with separate oil tank. Allows me to feed pure and clean 2 stroke oil (which is meant to lubricate and burn) and the OMP still regulates the amoint that is being injected.
Works well..
Can you show us pictures of your set up?
Reservoir location and type?
Thanks
Quote from: BlitzBoy;583084Yes you would have to have a ratio of 200:1 or 250:1 if running both, the main disadvantage it can lower the octane of your fuel when running both
Quote from: BlitzBoy;583089You can also in the Apexi ECU increase the amount of oil the OMP injects as well.
Some ECUs will not have this function or some ECUs you have to program an output to do control the OMP
i have replaced the OMP valves with the new version 99 spec ones and have read somewhere that they control the oil spread more evenly or something along those lines lol
so would it be possible, when mapping to just increase the amount through the apexi and run a different radio??
This is my adapter for blanking off the oil flow from engine to OMP. I have a braided hose which will go to a seperate tank. This is on a FC TII but still the same idea. OMP still operates but sends 2 stroke oil to the valves.
If I wanted to do the same to my 1993 UK FD?
What would I need and where do I get it?
Thank you.
Its from the USA and one of the rotary avaition firms over there,I will dig out the invoice or address for you.
You can get it through the rotary avaition website and click to the PCV website.
my setup is similar to the above pictures but I used the OEM OMP feed lines to the injectors
as a reservoir I just got my self apower steering reservoir of about half a litre from the junk yard.
You might want to find a reservoir with a level sensor so you can make a warning light on your dashboard when you are running low on oil.
Quote from: Speedworks;583421You can get it through the rotary avaition website and click to the PCV website.
my setup is similar to the above pictures but I used the OEM OMP feed lines to the injectors
as a reservoir I just got my self apower steering reservoir of about half a litre from the junk yard.
You might want to find a reservoir with a level sensor so you can make a warning light on your dashboard when you are running low on oil.
I used a catch tank with one of those plastic pipes that indicate level - but the warning light idea is a good one - as I\'ve managed to get it on the dregs a couple of times - I think mine holds about 1/2 L, but that\'s 500 miles or less of driving - depending on heaviness of right foot ;)
I\'ve got the same adaptor as Pete - and been running it on my vert as a daily driven car since the summer last year - no issues yet. I use TCW3 marine 2 stroke with detergents in it.