Data logit, oil injection, premix
 

Using the data logit can you completely turn off the oil injectors and just pre-mix with out removing the OMP and gear drive.

Using fc-edit(setting 3 page) the oiler vs water temp, will a setting of 0.0 completly turn the OMP off??

Anyone ever attempt this???

Even if you can what is the benefit?

So you are buring 2 stroke oil instead of 4stroke oil. Cleaner running engine with less carbon build up.

and to avoid buying things like this

http://www.rotaryaviation.com/oil_in...p_adaptors.htm

and this

http://banzai-racing.com/store/FC_oi...imination.html

I have never tested this. However, if you set all Oiler vs Water temp values to 0 you should try taking some datalogs and then posting them. Under the monitor window, select "Advance" only. Start the log and look at the "Oil" value. Drive around and take some data. Here is a chart of OMP "Oil" data. This is a 3rd gear pull on a '94 FD with sequential twins, using only its original OMP for apex seal lubrication. RPM, manifold pressure, TPS voltage, and OMP "Oil" value are shown. TPS and OMP were carefully scaled in the chart to represent their achievable minimum and maximum values.

https://www.rx7club.com/attachment.p...1&d=1291533483


I am unsure what the units for "Oil" really are. They may be related to the OMP position sensor voltage. The lowest value I have seen is 14 (mostly at idle and very low rpm/throttle/load) and the highest value I have seen is 120 at about 8000rpm. It may work out that the Oil value is 0 - 120 with 0 being completely closed (least amount of flow mechanically possible) and 120 being full open. I have read ttmott's OMP analysis but I'm not well versed enough in it to say whether oil flow can be completely stopped by the computer commanding a particular position in the stepper motor.

I don't think it's possible for the metering pump to shut off all oil going through the nozzles. IIRC from a thread (many, many years ago), even if the OMP is not working; since the pump itself is driven by a chain there is some oil going through the nozzles. It's just not metered any longer in that case.

Thanks for the insight. It is interesting how the "oil' and the "pim' have a dip in the same area on the log arghx posted, right about 4500rpm where the turbotransition is. So oil flow is pim(pressure) and rpm related.

Will try messing with the settings and watching the log. I premix already so i think I will be safe. If any thing I bet I have a little too much lubercation as is.

On the next motor I will delete the omp when I build it and have no worries...

Yes the oil injection is mostly based on rpm and engine load. On the series 5 FC that was calculated from an airflow meter according to an SAE paper on the subject. On an FD the load is calculated by the manifold pressure. Rotary engines up through 1988 metered oil based on throttle position and rpm, using a simple mechanical linkage.

please post a log. I am interested in seeing this

yea, i don't think you can completely shut off all oil flow but it is minimized. on most PFC cars who run premix i just set the values to 0 as arghx said and have them premix the oil into the tank.

i saw no issue in the need for the extra labor/cost of installing a blockoff plate and eliminating the pump, although it does cut down on the issue of the lines possibly breaking which generally is only an issue while removing/installing the engine anyways. the engine is already being lubricated and the possiblity of a "drip oil leak" from broken lines wasn't a huge concern.

I just unplugged my omp!

unless someone can chime in, i assume that the stepper motor does not default to a 0 setting or full closed in simple terms. for all we know it could default full open when no voltage is applied while the car is in limp mode.

My guess would be, if you simply unplug the OMP, it will stay locked at it's current stepper motor position as there is no voltage to drive the stepper motor.

Stepper motor will freeze in last commanded position if power is lost there is not a spring return. Code will be thrown for either loss of stepper coil inductive resistance or loss of pot for stock ECM.

A zero set in FC Edit will set the pump to minimum flow. Cannot terminate all oil flow.

If one wanted to stop flow from the OMP simply remove the oil pump plunger from under the pump's top cover (there are two in the Mikuni). Make sure to leave the sector valve and spring however. The pump will operate as normal and respond / communicate with the ECM but won't pump oil.
https://www.rx7club.com/picture.php?...ictureid=22835

The oil flow at minimum setting is very small so I would set zero and forget it if you were going to premix. https://www.rx7club.com/picture.php?...ictureid=22379Oil flow for normal operation is based upon engine load; PIM, RMP, and TPS V are components of engine load calculation.
https://www.rx7club.com/picture.php?...ictureid=28269[/SIZE]

Hmm, well I guess I should plug mine back in and set it to zero. Always learning something. :)

"The oil flow at minimum setting is very small so I would set zero and forget it if you were going to premix"

I need to recant this statement.
After further investigation this setting seems to only be a delta setting from a baseline oil injection flow profile. Setting to zero seems to only remove any plus delta for temperature compensation. Now, with that said we use negative values in other tables to "push" the PFC into certain configurations - I don't know it this can be done here.

Cewrx7r1, Arghx any thoughts here??

I don't have a properly configured car available right now for empirical testing.

I think that point is still up in the air. You are hypothesizing that this table adjusts only a pre existing water temp correction term in the oil calculation. So setting it to 0 would mean 0 adjustment based on water temperature, but oil consumption would still be delivered based on manifold pressure, rpm, etc. The other interpretation of the setting is that this table IS in fact the water temp correction itself, where "0" will indeed cut down the oil consumption to that negligible minimum amount.

The Datalogit software will not allow a negative value for the "Oiler vs Water Temp" table in settings 3. From my experience usually this kind of correction table is used as a multiple of an already calculated value, where 1.00 is 100% of the calculated value, .90 is 90% of the calculated value etc. Basically, I think setting it to "0" will in fact work but I can't test it right now.

All I can say is somebody needs to try different values in that table (including 0), take some logs, and post them up.

Sean, Tom, and Raymond,

How about putting two bolts in place of the banjo check-valves (after setting 0 flow).

Barry

^ kind of defeats the purpose of a reliable/simple/cheap/lazy solution, doesn't it? It's not like getting to the injection nozzles is a quick job

Agreed,
Simpler to pull out the pump plunger from the OMP. The OMP will operate perfectly but not pump oil. Should be able to get to the cover's four screws with the front compressor inlet taken off; maybe even without taking it off......

The best benefit is it can be reversed back to an operational OMP just as fast!