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ROBTRLRDR
09-22-2003, 07:36 PM
did you disable your oil metering pump? how did you do it?
if so what type of premix oil do you use? what ratio?
thanks
robert

itaracer
09-23-2003, 12:08 PM
You will probably get a lot of different answers to this question. I'm kinda new to this too and asked the same questions. Basically I have the metering pump operating AND mix my fuel. The fuel mix ratio advice will vary as will the type of oil you mix. Jim Downing recommends a 100:1 ratio. Thats about 1.25 ounces of oil per gallon of fuel. Mike Wiggins @ RX7 Heaven just rebuilt my 12A and recommended 2 stroke oil. Next you will get into the Hydrocarbon vs synthetic oils. On that subject I have no suggestions. However I do use synthetic oil in my other cars as well as synthetic gear lube in all my cars.

Festus E. Simkins
09-23-2003, 12:19 PM
I believe that in IT it is illegal to disable the oil injection system. Currently I use Yamalube "R" at a ratio of 1 oz to 1 gal (12A engine). I have never had a problem even when it ran REAL LEAN, i.e., burned a hole in the header and the exhaust temp guage topped 2000 degrees F. Just my experience. Yamalube is a little pricy but I like it. I also know guys that run cheaper 2 cycle oils and they do OK too.

Drive well.

Davidov
09-23-2003, 03:22 PM
http://www.rx7club.com/forum/showthread.ph...ighlight=premix (http://www.rx7club.com/forum/showthread.php?s=&threadid=221292&highlight=premix)

Most everyone I have heard, uses 1oz. to 1 gallon, or 128:1 oil:gas.

If you're OMP is not completely blocked off, it's generall not recommended to run Synthetic Motor Oils.

jake7140
09-23-2003, 04:54 PM
My metering pump is connected (rules) and I still throw in a couple oz of 2-stroke to provide a litle extra in the high rpms. I use go-cart caster oil, burns really clean. In my 2-stroke race bikes, I always used Yamalube, so I agree that it's great stuff.

I would concur on the 100:1 or 128:1 ratio wiht the pump disabled, from past research only.

To disable the pump, there is a little rod that goes from the carb linkages down the psngr side of the engine. The oil metering pump is about 2in long, 1/2" wide attached to the side of the case.

As for synthetics, my read on them is that they should not be used in the combustion chamber as they do not burn off like "real" oil and thus build up deposits and eventually break apex seals. I believe some still use it in the oil pan if the OMP is disabled.

------------------
Steve
[email protected]
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bcarter
09-23-2003, 06:28 PM
If you want to disable the OMP, take it off the housing first. There is a small flat piece of metal sticking out of the pump that goes into the housing, which actually turns the pump. Pull that out with a pair of pliers, and replace the OMP on the housing. Then, block off the two exits for the tubes on both the OMP and the carb. Voila.

------------------
G. Brooke Carter
Wheat Buckley Racing
# 10 Challenge Car
2003 Class Champion
Calgary, Alberta
http://www.guyons.com/pictures/photos_cars/06_30_rx7_brook2_150.jpg

ROBTRLRDR
09-23-2003, 09:03 PM
thanks guys finally some answers
i use yamalube and maxima in my bikes as well. i use both at about 80:1 and get great results.
iT doesn't sound to hard to disable the omp, thanks. i just didn't want to mess anything up by doing it wrong. as far as i can tell the rules just state it can't be removed. i use about a qt. of oil each track session and that just has to be bad for the engine. plus it smokes so bad when i back off or shift i almost got black flagged. i was questioned about it.
so i'm going to try this out because i heard that is what is done.
thanks again
robert

[This message has been edited by ROBTRLRDR (edited September 23, 2003).]

[This message has been edited by ROBTRLRDR (edited September 23, 2003).]

Speed Raycer
09-23-2003, 09:21 PM
You didn't get black flagged because of the OMP... you got black flagged because your side seals are probably failing. The OMP doesn't pump near enough oil to get you black flagged. Most premix ratios have more oil in them than the OMPs do on their own.

Try some Resolin (Sp?) or SmokeBGone. Resolin is available at NAPA and cured our smoking problems, and ours was so bad the car behind us would disappear when we lifted in a corner! Smoke B Gone is available at Autozone, but I've never actually tried it.

[rules nerd mode on] The rules don't say that it can be disabled either and IIDSYC...[/rules nerd mode off]

I'm using Redline 2 stroke (came with the new car) at about 128:1 and am fairly happy with it so far. Hmmmm guess I should check the status on the OMP huh? LOL


{edit} oops... oil seals not side seals{/edit}

------------------
Scott
It's not what you build...
it's how you build it

<A HREF="http://www.pfmracing.com" TARGET=_blank> http://home.swbell.net/srhea66/PFMSigPic.jpg
www.pfmracing.com (http://www.pfmracing.com) </A>

[This message has been edited by Speed Raycer (edited September 23, 2003).]

[This message has been edited by Speed Raycer (edited September 24, 2003).]

Scott Nutter
09-23-2003, 09:52 PM
I am guessing that 1qt per session, per weekend for that matter is too much.

I too have thought about this, I've always run the stock OMP and probably still will. But I've had a few incidents recently where my Autometer tach started reading wrong(too low of course)! and then to discover that the OMP metering rod was not connected to the carb http://Forums.ImprovedTouring.com/it/frown.gif

All seems fine but was wondering about that little added protection. I am not concerned about HP gains as the only mods done are a header and K&N filter(stock blue snorkel) But at the same token don't want to loose 10%. Is running 128:1 going to kill me, or those that are lapping me?


P.S. I've done the ATF thing and had my cities finest visit to make sure I was OK! And really don't want to subject my fellow racers nor the much underapperciated workers to that kind of abuse.

lateapex911
09-23-2003, 10:01 PM
.....yes, the puffs of smoke are due to the sudden vacuum in the combustion chamber, caused by shutting the throttle at 8K rpm, sucking oil by the oil seals, and into the chamber. Backing out gradually, rather than jumping off the throttle will alleviate it to some degree, but of course, replacing the oil seals is the ultimate answer.

------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

Allen Brown
09-24-2003, 02:34 PM
Just to add a comment about the premix oil...Yes, you can use synthetic...Just make sure it is a synthetic two stroke oil.

My OMP puts out basically the idling amount of oil. I run a Synthetic crankcase oil (in the crankcase of course), and then I premix a synthetic 2 stroke oil at 100:1.

No problems....

miketrier
09-25-2003, 07:37 PM
I've run the same car and engine since 1999 and it wasn't new when I got it. I wired my OMP fully open and I use Castrol 5w50 synthetic oil. I don't mix oil with the gas. Works for me. No problems so far.