I've had a 87 RX7 for a while now, and when i bought it the previous buyer had removed and blocked off the oil metering pump, as well as all the injectors. (plugged) . So i've always run about 1oz of 2 cycle oil per gallon of gas in the gas tank. Basically everytime i fill up i put 16oz of 2 cycle in the gastank after the fill. I was wondering if you guys recommend doing this, or if you think it would be safer if i install the oil metering pump agian? Basically just wondering whats best for running a car that makes 400+ HP, thanks.

 

There are pros and cons, what you are doing is called premix and you are doing that at the correct amount of 1oz to 1 gallon.

Bottom line, is that if you don't mind continuing to premix then there is no reason to go back.

 

You should add the oil before filling the tank, it'll mix better. And yes there are advantages to premixing but unless it's an all out race car you should be fine enough with the OMP. A nice upgrade would be to simply add an oil (2-stroke) reservoir an have the omp pump that instead of the regular engine oil.

 

Really the only downside to premixing-

other than the hassle at fill up time,
and the extra expense,
and the possibility that the premix oil might clog the fuel filter if it gets sucked up before it fully mixes in cold weather leading to a lean condition and grenading your engine,
or the possibility of forgetting or of running out of oil in a pinch- ruining your engine, or...

Uhhh, I lost my train of thought...

Ok right! The only downside OTHER than

the hassle at fill up time,
and the extra expense,
and the possibility that the premix oil might clog the fuel filter if it gets sucked up before it fully mixes in cold weather leading to a lean condition and grenading your engine,
or the possibility of forgetting or of running out of oil in a pinch- ruining your engine, or...

is that you are no longer injecting crankcase oil, so you can experience oil dilution that reduces the lubricity of your oil. You need to change your oil more often. How much more often? Beats me!

 

The best bit about running premix and a blocked off OMP is that you can run a decent fully synthetic oil and not mineral oil.

 

i been premixing for a long time...due to a microtech.....i run only 8 ounces on a full tank of 93 octane....thats if im going to beat on it....alot of people i deal with run about 8 ounces and that works fine...alot of people like to run a ton of premix....but all the cars we dyno....8-10 ounces works great
if you end up not haveing oil with you while at the pump...just fill up and drive the car normal....dont beat on it at all...and you will be fine....ive driven plenty of times with out premixing and never had a problem....i wouldnt recoment driving everyday like that

 

thanks guys that deffinatly sums it up for me. appreciate it!

 

What If I just want to premix before i go to the track do i really need to block off my OMP?

 

No, the omp will just add more oil. Premix a little if you really feels it's necessary (say 4 ounces?).

 

I run the OMP, with a adaptor so that it pumps 2 stroke oil from a resevoir, the good is that 2 stroke is meant to be burned- obviously.

More oil changes? First im hearing about it- but if thats the case who cares?

Getting my adaptor to operate correctly on a S5 motor took a small custom fabricated piece to be made. The person who makes the adaptor had made a handfull of "adaptors for the adaptor" so you can run the set up on s5 motors, but there was no demand so he stopped making them.
The adaptor was actually originally marketed for rotary engines in aviation duty.

Nice thing about the adaptor? You dont pump oil ALL THE TIME, it works off throttle linkage. You dont sit in traffic spitting 2 stroke out the pipe.

Bottom line on the adaptor? a good thing- not a direct bolt on easy thing, but useless for a track car.

 

what about this:
http://www.jhbperformance.com/products.php#oil_system

 

basically sounds like a kit that has you thread a barbed line into your OMP, how it regulates the oil I dont know?