Black1993rx7

I'll probably be called a stupid for this one... but why not cap off the oil injectors and premix it all in the gas tank like a two-stroke?

ejmack1

been doing it for years....

MOBEONER

iTrader: (18)

people here have done that.

rynberg

Why eliminate a system that works very well AUTOMATICALLY and replace it with a system that requires operator input?

MOBEONER

iTrader: (18)

because some of us think premix burns better than car oil

rynberg

Well you can think it all you want but in over 6 years here, I've yet to see an engine with oil-related damage (other than missing oil...). The stock oil metering system works very well, even on highly modified cars. If you want to run 2-stroke oil in it, you can even run one of those adapters that feeds the OMP with a separate reservoir.

Black1993rx7

why isn't there a write up in the stickies or archives about this? I did a search.

For those that have done this, what differences do you notice? does it run smoother? power gains? smoking?

rynberg

It won't run smoother and you won't gain any power.

The database is being rebuilt, hence the search function not working very well right now. There should still be plenty of older threads out there on "premix" or removing the OMP. Probably a lot of info in the Haltech forum also.

MOBEONER

iTrader: (18)

you could be right,but when you open up a high milege engine all the black crust,is that not old burned oil,i could be wrong i have alot less experience than you but i am just speaking on what i think burns better

ejmack1

I just did it because i didn't feel like putting the OMP back on

rynberg

The black crust is carbon build-up, not necessarily from oil. My engine was pretty clean when opened up at 85k miles.....synthetic oil, stock OMP system, and plenty of hard driving.

Wargasm

I agree with some of the other comments...

Yes, you can do what you want... it will work.

But... will it really provide a benefit on a mostly-stock daily driver or weekend cruiser? No. In fact, I think that it opens the door for -causing- a problem when someone forgets to put oil in, or miscalculates the correct ratio.

Some folks do it because they like the simplicity of no OMP, some do it because their engine management system is aftermarket and won't run the pump, and some do it because the stock one became damaged and they don't want to pay for a new one. I don't think it's better to remove it/replace it with premix... just different.

My car has a decent amount of modifications, but I still run the stock OMP system plus I premix in a little extra like an insurance policy ( 1/2 ounce of two stroke oil per 1 gallon fuel).

TitaniumTT

I like the way you think. Going stand-alone and will be sportin' an M800 so I can keep the the OMP & rock the twins.

DAMN I like the way you think.

Exactely what I'm doing. I've caught SOOO much smack on the other forum for mentioning that. I have alot of marine experience, 2-stroke o/b's and some of the failures that I've seen were oil related but it was becuase there was either no oil or water in the oil. When the "oil" was injected the water that it was got into the bearing and BOOM! A few other points that I'll make. O/B's or any marine or aviation motor (think Rotary Aviation or Real World Solutions ) for that mater is under a MUCH higher "duty cycle" or load if you will than a car motor. Take my boat - 21' 200HP 100% throttle =~60knots, 75% throttle =~30kts. You get the picture. Not to mention the oil injection systems on OB's need to lubericate rings, rods, pins, and main bearings. I dare say in a 300HP OB screaming along @ 6000RPM there is ALOT more load on those bearings than there are on the seals that we need to lubricate.

The other cause of failure was no oil. You should watch some of these fools start thier OB's. Especially the Yamaha's with older fuel tanks. When the switch to ethanol was made, all the sludge in the tanks was suspended and the ethanol attracted the inherient moisture. Yami's have really small jets and orifices in the carbs, carbs would clog, people were trying to start thier motors full throttle and when they would finally set off, they would scream past redline with little or no oil being injected

Then there is that whole variable thing that both the OMP and the 2 cycle marine world share. 25 some-odd years variable oil injection has been around in an entire industry. If you go buy a $16,000 Mercury OB you will get an elecronic multi-point oil injection system.... TODAY

Buzzardsluck

I premix for no reason other than the "oil all over" theory of thinking. If you think you will forget to add oil to your fuel then you should probably tatoo your name and address on your arm in case you forget that also.

When I had my engine out I just left it off, if the engine hadn't gone I wouldn't of taken it off.

turbojeff

iTrader: (30)

I agree.

People, don't modify stuff that works and requires to you do something at EVERY fill-up.

vkotis

i premix a little along with my OMP. i was wondering about premix only: when you come off the throttle and the injectors shut off, there is no lubrication for that time, especially when dropping from high rpms. wouldn't it in turn be worse than having the OMP on constantly lubing???