I was under the impression that there are two versions of the 500 engine: The carbed "HO" and the injected "EFI" version. I just noticed that my wife's 2006 has BOTH logos. What gives?

Thanks!

 

WAATV..

The carb and EFI version both have the 500 HO logo.. The difference being the carb model dosent have the "EFI" sticker on the headlight cover. The carb model dosent have that on there.

BTW.. How did Macks treat you?? Curious..

 

when polaris had the 500 atv engine in 2000 it was just a standard 500 motor, in 01 they switched to the high output motor and carried it through to this model year so when the efi engines came out they kept the same motor but just added the fuel injection.

 

OK, thanks everyone. I thought "HO" was related to the carb system for the normally aspirated engine, which would have made it mutually exclusive with the EFI version. I wonder what "HO" means? If it's the same displacement and doesn't refer to the aspiration, what does it mean?

Mack's was great. They took a VERY long time getting the work done - quoted me about a week and took nearly three - but the work was done properly and the price was reasonable. I'll be back if/when I need something more done... including buying the mulching kit for my wife's JD LX280 in the spring!

 

Afternoon WAATV
"I wonder what "HO" means?"
HO= High Output, I believe,,

 

Well, Yes, I knew that much [grin].

To be more specific, what I meant was "How does an HO-designated engine differ from a non-HO engine?"

 

the H.O.'s became available mid 2000 in the 2000.5 model year

 

What is the HP difference between the HO and non HO engine? I wouldn't put it past any company to just slap HO on the side and call it 'all new'!!

 

I believe polaris put a different cam from non ho motors to high output ones, made have a bigger stroke and also changed to dont quote me on this but i think they changed to a 36 mm carb from a 34?????, I know it increased the horsepower by about 20% from the standard 500 motors. i dont know if any of you remember but i forgot to mention that polaris introduced the 500 HO in 1997 on the Scrambler 500. In other words, your wife has a pretty sweet ride[img]i/expressions/face-icon-small-smile.gif[/img]

 

THE HO ENGINE HAS A LARGER CAM AND CARB AND MANIFOLD BOOT.ALSO A HIGHER VOLTAGE CDI BOX.ALL THIS WILL ENTERCHANGE TO THE OLDER NON HO ENGINES.I PUT THE HO CAM IN MY 97 500 EXPLOER AND PORTED THE HEAD OUT FOR MORE BREATHING DO TO THE HIGHER RAMPING OF THE HO CAMSHAFT.ALSO DRILLED OUT THE MAIN JET AND THE CARB SLIDE VACUME HOLE NEXT TO THE NEEDEL.