I have been using both without any problems that i can see, this is just the stock OMP and not the one you refer to Hamza.
Is this ok or have i been missled and should stop using/doing both?

 

Hamza734,

If the problem with regular engine oil is that it is not designed to burn cleanly, then why not recommend dropping the injection altogether and just run premix using 2-stroke oil? Why recommend increasing the injection amount, adding more oil that doesn't burn cleanly, and then add 2-stroke to that? Does not compute... but thanks for your info, I did not know the current thinking on this issue.

 

By early I mean RX3, RX4, FB

If you still run the stock OMP, 4 oz per tank of premium should be plenty. Without the stock OMP, 1 oz per gallon is the right ratio. For racing, up to 50 to 1 (~2oz per gallon). The only reason this topic comes up so often is that with stand-alone EFI, you usually have to block-off the OMP (Power-FC is the exception). I don't think its possible to block-off the OMP w/o running a stand-alone....If the OMP isn't working the ECU assumes it broke and send the car into "break-down" mode (max RPM 4K)

 

so Hamza, break it to me nice and level... i'm putting a PFC in my car and 4oz per 20gal isn't alot of oil at all... do i really need it in there? i know it aids in lubing and all, but if it clogs my injectors and pops my engine... ya know? i'm getting my PFC put in and installed soon.

 

The reason for not dropping oil injecton is that on cars with electonic OMP's (all 89-95 RX7's) you can't simply remove the pump with the stock electronics. I think the best all around solution is to modify the OMP to use two stroke. The part is only ~$100. As for modifying the OMP for more oil, the more lube the better.

 

Bottom line is you won't need to do it. You guys can check this out for the best info on the subject:
http://fc3spro.com/TECH/FAQ/premix.html
It's written for the FC, but most of it also applies for the generations.

 

By FB you meen SA22C right? First gen? I'm lost...

 

I notice premixing MMO result in lowering MPG too. I was at 15-17 MPG, untill I start premixing and it went to 12 MPG. I'm beginning to worry premixxing MMO causes my motor to...... lets just hope it's not my motor

 

With some of the aftermarket ECU's (AEM) you can adjust the premix accoring to a Duty Cycle table, that involves, Throttle Position, and RPM's I think... Which still wouldn't allow you to go over 100% on the stock pump, but I wonder what the stock pump operates at !?
%50-80% ?? So adding some extra duty to that map may get you out of pre-mixing...

What about making a reservoir, like the water injection guys do, and drawing .... whatever you want from it, have a level sensor, and fill it like gas, windshield washer fluid etc... when empty, or low...
You might even be able to add a bigger pump !???

 

IMO all this pre-mixing crap is worthless. 99% of the FD's on here are going to take a **** from other reasons(crappy tuning,coolant seal,etc..) LONG before it dies from not putting premix in.

 

I 100% agree. get the 93 octane fuel and **** this pre-mixing ****, Rich. Just another thing to screw around and bother with that you don't have to.

 

I thought SA's were 79-80 rx7's here in the US then FB's from 81-85. Though many people I talk to have no idea what an SA is.
Just to stay on the topic a bit....I have the PFC and thus still use the oil metering pump, and I also use Mobil 1 10w-30 and premix ~5oz of penzoil synthetic stroke oil per fillup. I get about 20 miles per gallon cruising and run an AFR of 14.7-15 under vacuum. So I dont notice any ill effects from the premix. I would not think that premix would gum up injectors, it is a very lite oil in the first place and when mixed into the gass begomes even lighter.

Bob

 

I heard it could knock your octane up a point or two, since oil has a higher flashpoint than fuel...

 

I totally agree (twice in the same week -- is it Armageddon, Fumanchu? ).

I don't recall ever seeing anyone lose an FD motor for oiling reasons (other than running out of oil or low pressure--mechanical). The concern over oil in general on this forum is just shy of ridiculous.

Pre-mixing for street driving is a waste of time/money IMO (unless you don't have an OMP, obviously).

 

I don't disagree, I think it's a PITA, and not neccisary, since you have a system allready in place, I guess for the worry warts, I'd say take that system to 100% before you start premixing...
BTW I thought Pettit's little racket was a nice incentive for people to wonder about premix !

 

This is getting scary Rynberg I must be getting old. Do you have an extra walker I can use?


This premixing crap falls into the same category as 1000 mile oil changes and 5,000 mile fuel filter obsessions.

 

Nope, but you can borrow a cane from adamc....

Yep, also don't forget the loonies who think that hitting 190F water temps is too hot.

 

1. Marvel Myster oil isn't proper premix. Get 2-Stroke oil.

2. I pre-mix on the street, even though i acknowledge that it isn't entirely necessary. But, when you have a 11-year old car with a PFC that doesn't have a mechanism for allerting you of a MOP failure (which does happen) the way the stock ECU does, I think squirting a few oz. of oil in the tank is good insurance.

 

That's a very good point Ptrhahn. However, in my case, I'm not concerned about that as I replaced my OMP 2 years ago with a brand new one ($1400 for just the OMP!).

 

have you changed your fuel filter lately?

 

former porsche guy, yeah, it just got replaced about 5k miles ago so it should be good to go... i swear, i only get this after i've premixed and it takes like two FULL tanks of 93 to get it running right again. i think i'm just gonna say screw it oh well, it was worth a try.

 

it's a tough call... other things with this car have shown to be insufficient, I don't see why the omp can't be insufficient as well. the problem is that nobody knows if it's a good idea or not. untill lots of people start getting MUCH more mileage out of premixed engines vs non-premixed engines, nobody will ever know. I think of it as a reliability mod for my tired, daily driven, 65k mile engine .