Viper Jetting

[woolyviper]

my 03 Viper is jetted stock. I noticed that the powervalves get gummed up quickly and that the inside of the pipe looks a little rich on the motor end. can i safely make the midrange leaner to improve the combustion without having to worry about taking it too lean. I would imagine the factory jetting is on the rich side. Any suggestions?

 

[yahadriver23]

My plugs were black, so figured it is running a little rich right?! Anyways, better then running lean, and the carbs haven't been changed sense it left the dealship. What color are your plugs? powervavles are going to gum up in these that is a given

 

[snocrosser]

What kinda oil ya running? That will make a big difference. Yamalube is famous for stuck power valves. Try Amsoil dominator, great stuff!

 

[yamaholic22]

Stock viper jetting really isn't too bad, and the powervalved engines like a little more fuel to run strong anyway. That being said, you can safely drop a size on your mains if you are looking to lean it out a little. Personally i would leave the needles alone, haven't changed them from stock setting on an unpiped viper but they run so snappy in stock form, might develop a lean bog if you lean them out.

 

[woolyviper]

I run Amsoil Interceptor - I saw a little improvement, but when it's warm out, the valves get gummed up faster than usual.

 

[skidooboy]

playing with fire. mfgs make the sleds leanest in the mid range (needles, pilots) cause that's where you trail cruise, that's where they need to get the best mileage. vipers are notoriously lean here, do not mess with that. as for powervalves, you need to clean them alot more than the manual says. oil, jetting have alittle to do with this but mostly it is in their design to have this oil residue caked and baked on. they are not like other mfgs. valves that stay alittle cleaner. my srx's and viper has always had dirty valves every time i checked (approx 500-750 miles) this is with tempaflow, and leaner oil pump settings. you play the edge sometimes you fall off. jetting perfect, will not yield super horsepower. you'll only get a few if any. and when you mess up, temps change, pick up a piece of dirt, snow, water, or bad gas, your edge just caused you to miss riding and lots of time and cash. been there done that. ski

 

[Viper_Jim]

Jetting can make a huge difference depending on the elevation of where you ride....I went with smaller pilot jets because where I live the elevation is substantially lower than where the sled was spec'd for, this is worth looking into....made a huge difference in the performance of my sled....better gas milage and smoother throttle response.

 

[S.S.Viper]

I asked the same question awhile back...but was also worried on really cold temps...I have a Carbon Tech reeds and Spacers...I figured these would "richen" it out enough for me to drop the needle down one space...but was also told not to...
So I'm curious then would the Tempa-Flow or Vari-Flow help in this department?...and then when it gets colder..you can adjust on the fly?...