[crash]

I have got the square and the sled runs stronger than most f7's. I don't know if this means anything or not. My plugs are usually nice choclate brown.

If I'm not mistaken there are three codes, circle, sguare and triangle.

 

[arcticmannf7]

Circle=richer
Square=middle
Triangle=leaner

It has been my experience that the triangles run right on the edge, whereas the squares are more reliable in the long run (several years). The squares are also the most common. Triangles should always run good gas (90+ octane) just to be safe.

 

[jleosnow]

Not to sound stupid but...... where do we see this on our sleds??
-John

 

[Fire Chicken]

I believe they are talking about the symbol on the top of the ECU box.

 

[arcticmannf7]

The ECU is mounted on the airbox. On the lower right corner will be the shape code (viewed from the bars facing forward). Hope this helps.

By the way don't get mad if you have a circle it means you are the safest to run a D+D or Speedwerx pipe and lose 13 or so pounds off the nose. All the ECU's run great and at most .5 to 1 sled length differance.

 

[duke1n]

So what determines which ECU your sled came with?

 

[arcticmannf7]

Luck of the draw, I'm not sure how the ECU's get doled out and I know that the factory does not keep a record of what serial # got what ECU.

 

[jleosnow]

Originally posted by arcticmannf7@Jan 12 2003, 11:00 PM
Luck of the draw, I'm not sure how the ECU's get doled out and I know that the factory does not keep a record of what serial # got what ECU.

Triangle for me...... I don't know if I should consider this to be good luck or bad luck...
-John

 

[rob]

mine's a triangle. I get great mileage and performance, but I've always run 87 octane with no problems..

 

[toolboy]

Why would a company make three different fuel maps and/or timming changes on a sled then they want great performance and low warranty expense. All engines run a bit different. I am looking for a different answer for the codes. My has already been replaced under warranty due to a wiring problem.toolboy

 

[LUVMYF7]

Mines a square, no problems yet !

 

[chill50]

Top speed 97 MPH, F7 standard on groomed trails. 101 MPH on packed down seasonal road going down a hill. I must have a circle

 

[Larry]

What color injector corresponds with the differenct ECU's?? My ECU is square with yellow injectors.

 

[arcticmannf7]

The color of the injectors is the same for all the ECU's, however their flow is matched.

 

[Mike C]

This is a new one for me. Now I am going to have to trek over to the garage, uncover the sled and look. Although, if I do, what is the difference, not like I am going to change it.

 

[racetechus]

your sleds symbol is determined at the factory using a flowbench. the perfect ratio of air to fuel is 14.1 to 1. seeing as theres inherent varibles in engine casting and machining they test using a flowbench and decide what range your engine falls into.

 

[racetechus]

your engine was tested using a flowbench to determine its flow characteristics.basically how many cubic feet of air fuel mixture can it pump per minute. this dictates the symbol on your ecu. since there are inherent tolerances in casting and machining no two engines will be exactly the same. since the perfect ratio of air to fuel is known to be 14.1 to 1 your engine after being flowbenched will fall into what arctic cat has narrowed to 3 ranges. this is why there are different symbols. no you cant put a triangle bx on your square tested engine without risking failure. hope this helps answer the quandry of why

 

[messickzr]

Man you learn something every day.

 

[highlander]

Yes thats rite..... :wacko:

 

[firecatsnopro]

A lot of you are WAY off on this subject!!!!!!!!!!
The injectors are matched to the ECU. You have circle, square or triangle injectors and that is determined by the OHM reading of the injectors!!!!!!
THE INJECTORS HAVE THE SAME MARK AS THE ECU, THE FUEL RAIL IS ALSO MARKED ON THE F-7 IF YOU LOOK!!
You can not interchange ECU's or you will run rich or lean, depending on the injector marking.
The outcome of the matched setup, is that all machines RUN the same!!!
The reason behind this is when you buy a lot of 20,000 injectors, they do not ohm out and flow the same, and you don't throw out the one's that are out of spec. you use them with a richened or leaned fuel curve in the [email protected]!
YES i'm a certified catmaster!