Second Gen - Electronic Oil Metering Pump

[Fallout]

Guys,

i bought this 91 second gen ITS car. The oil metering pump is running as stock.
I know from my first gen, that i did not run the OMP (or ran it at idle?). Instead i used premix 1oz a Gallon.

What should i do with this one. Leave the OMP running an rely on it? Or use premix on top of it? Or use premix and "deactivate" the OMP even though i have no idea if this is even possible for an S5 engine?

Your input is appreciated.

Matt

[it7rx739]

Use premix on top of it.............

[seckerich]

If you are running a stock computer it will go into limp mode if you disable it. No big deal, just do not run synthetic oil and add 1/2 to 1 oz/gallon of a good premix oil.

[tdw6974]

just do not run synthetic oil ?? Hmmm? now I am confused no Synthetic oil for racing ?? T Weaver

[Andy Bettencourt]

Just use sythethic oil with low ash content.

[Fallout]

I usually use 2 stroke full synthetic for the premix.
I guess it is supposed to burn clean.

Assuming i would run the good ole 20w50 i used to run in my first gen, could any issues arise out of having mineral oil and synthetic at the same time in the combustion chamber?

Any recommendations on "low ash" synth oil?

[Andy Bettencourt]

Any recommendations on "low ash" synth oil?

Google is your friend:

http://mcgeerf.tripod.com/americansyntheticoil/id17.html

[Prof. Chaos]

If you run premix, are you still legal should they take a fuel sample?

[Eagle7]

I like to tell anyone nearby that I'm mixing in my super-secret power-juice.

[Prof. Chaos]

As a last resort I decided to read the GCR, and it says premix is allowed in non-SS classes.

[finger lock]

I run the stock OMP with my 3rd gen RX7. I also premix ~1oz/gal of Redline Two-Stroke Racing oil. For motor oil I have always used Valvoline 20W50 non-synthetic. This combination has kept my motor happy through all sorts of abuse.:023:

Guy

[gpeluso]

dumb question.....so does the ash in the oil only matter if the oiling system is still operational? My system is not hooked up and I do premix with WalMart 2cycle and use Castrol 5x50 full synthetic. I see that the Castrol has a higher content in ash.....is this bad in my situation? Should I use something else?

Greg

[Continuum]

I've got an 89 NA S5 that I prepped years ago for ITS and have been taking to track days since 2005. I've had the OMP in the car but detached for years while premixing. I use any 2-stroke oil rated TCW-3 (low ash) and have never had any trouble at 1 oz per gallon.

I think another aspect you may want to consider though in your decision is whether it is legal by the GCR to disconnect the OMP. I'd love to hear other people's opinions on whether this is really something people get picky about and you have to leave on or you can either detach or remove altogether. Note removing from an S5 will require R-tek chip or stand alone to avoid ECU issues. I'd hope this is a reliability modification that people could care less about debating legality.