well, i've come to the realization that my engine doesn't like to have oil in the gas AT all. when i premix, my gas mileage DIES. it was like 18-19mpg after i changed my plugs. i added some MMO as recommended and it dropped to like 12-14mpg. i ran a few tanks (2 full tanks) of 93oct through and it went back up to 18-19 again (actually got 25 on the highway). now i decided to give it one last shot and its back down. it think i have to stop doing this. there's no way its good for the engine.

on a more exciting note... i'm getting my PFC installed and tuned on the 22nd! yay! i can finally put on my intake and enjoy all the goodies i've added

anyone else have that problem with premixing? otherwise, just thought i'd share

 

havent had a chance to premix my FD yet because its not driving yet but my FB runs great premix'd but its also a carb'd 12a so ...

 

You drive an FD and are concerned about the gas mileage.

 

hehh , my 12 mpg fb aint much better




hahah ***** 1!!!!!!111!!

 

i'm not concerned about the gas mileage, but for some reason adding something to the fuel which results in a 25% decrease in gas mileage tells me that maybe its not working the way its supposed to... i guess that could just be me thinking i know what i'm talking about though i just wonder if its having a negative effect on my plugs or something ya know? need to pull them this weekend and check them out. only have 5k on them, so they should be good

 

12mph, huh? Sounds like you have a blown seal

 

haha i just saw that !

 

**** im drunk as hell **** you alls heheee

 

how much mmo were you adding?

 

dude wtf is this mmo stand for ? all i know is i went to the ghetto *** kmart by me and bought some 2 cycle and put that **** in while hte dude at the gas station thought i was crazy for putting oil in my gas tank

 

premixing shouldn't affect your gas mileage that much unless your adding a ton of the stuff .
it might, however, have an adverse effect on your injectors (plugging them up or something)... that's worth considering.

 

i was adding 4oz per like 15 gal fill up... was that way too much? i thought that's what it was supposed to be.

 

no, i just added 6 oz to 8 gallons of gas, im not sure on the FD's but on the FBs i know you can almost do like 1 oz per gallon, i have to learn the FD's cause mine will be done in about 3 weeks so ...




thanks mods

 

there is no way 4 oz of mmo decreased yor gas mileage. 4 oz it would take a mass spec to find it!

 

Bad mileage has little or nothing to do with pre-mixing. Furthermore, your subject line is flat wrong. Pre-mixing is MUCH better then oil injection. Look back at the early SAE papers from Mazda, or better yet, look in the "The Rotary Engine" by Kenichi Yamamoto....oil injection was a compromise solution for road cars. Basically, it saves the owner/driver the hassle of having to pre-mix, and it acts as a safeguard from forgetful owners destroying engines. All of Mazda's racecars from the original Cosmo to 787B pre-mixed...

 

Bad mileage has little or nothing to do with pre-mixing. Furthermore, your subject line is flat wrong. Pre-mixing is MUCH better then oil injection. Look back at the early SAE papers from Mazda, or better yet, look in the "The Rotary Engine" by Kenichi Yamamoto....oil injection was a compromise solution for road cars. Basically, it saves the owner/driver the hassle of having to pre-mix, and it acts as a safeguard from forgetful owners destroying engines. All of Mazda's racecars from the original Cosmo to 787B pre-mixed...

 

I run 1oz per gallon. It didnt affect my mileage. If you think about it even 1oz per gallon is VERY little.

personally I wouldnt use MMO, I'd use a good high quality 2stoke synthetic. I use Mobile and Amsoil. They are both good. MMO, is not a synthetic oil and I wouldnt run it.

STEPHEN

 

Hamza 34,

Are you saying you believe the oil injection system in the FD does not provide sufficient oil to lubricate the seals in the absence of pre-mixing? Wouldn't Mazda have adjusted the injection amount to the "correct" value during the initial design of the engine?

 

I agree with Steven. I don't know what that MMO stuff is, but any TCW3 two-stroke oil will do just fine.

 

well, i got the MMO cause it seemed like alot of people on here were worshipping it in the pre-mix threads... what could the strange difference be then? do you see why i would think it might be the pre-mix based on the use/mpg correlation i'm seeing?

 

The stock oil injection will provide enough oil to lubricate the seals without pre-mixing. The problem is with the oil itself. Regular engine oil is not designed to burn, and dosen't burn "cleanly". Moreover, the stock oil injection is calibrated to run lean (i.e. provide least possible amount of oil) for emissions purposes. If you look in the Racing Beat tech manual, they recommend increasing the amount of oil the OMP injects (before you ask, this is only possible on the early cars). I think the two-stroke oil also has superior lubricating properties....

When I switched to premix, I noticed the car ran considerably smoother. A positive consequence of premixing is that you can run synthetic in the crank-case.

 

Best of both worlds:

http://rotaryaviation.com/oil_inject...p_adaptors.htm

Run two-stroke AND use the oil injection. Really, the only down side I sea to premixing is that it'll clog your fuel injectors faster.

 

"MMO" is short for Marvel Mystery Oil, a very ancient product originally offered for lubricating valve stems and upper rings in piston engines. Here is what it says on the can:

"Marvel Mystery Oil is a product of the highest quality. It is light bodied but higher in film strength than many of the heaviest oils. It is friction reducing, wear resistant, gum solvent, and penetrating. It is heat-resisting and when subjected to the high heat of internal combustion produces, not carbon or gum, but a lubricating residue.

Extreme cold does not solidify Marvel Mystery Oil. It flows at 60° below zero.

Can be added to conventional oils to strengthen them or lend them the characteristics needed for best lubrication. Will prevent sticky hydraulic valve lifters and counteracts harmful combustion residues."

(It may even cure dropsy.)

They recommend adding 4 oz per 10 gallons of fuel.

I had used it for a long time and my engines have lasted long periods, but then I change oil every 3K miles, use Techron, etc, so now that I no longer use it I have no idea whether there will be changes I will notice during the remainder of my lifetime.

 

so i should occasionally run some fuel injector cleaner through my gas just to keep them nice and unplugged i have 93 (produced in like MAy of 92, is that early enough to change the OMP injects? or were you talking about early FB, FCs... how do ya do that anyways?

 

so i should occasionally run some fuel injector cleaner through my gas just to keep them nice and unplugged i have 93 (produced in like MAy of 92, is that early enough to change the OMP injects? or were you talking about early FB, FCs... how do ya do that anyways?