stock 03 viper jetting?

[blueblooded]

Anybody know what stock jetting is on 03 viper 700?
I'm at sea level....wanna jet for -10 degrees Fahrenheit.

 

[mrviper700]

156.3 mains, 45 pilots, needles at 3.0 are what comes in it stock. jets are plenty safe at that -10 degrees, I would however raise the needles to 3.25 in ANY year viper , that's the 4 th groove down from top but put BOTH plastic shims on top of clip, you will avoid the mid range burn down from a lot of timing and increased compression in the 2 cylinders of the viper engine then.

 

[blueblooded]

Thank you mrviper!!

 

[blueblooded]

Ok.so I moved needles to 4th clip
156.3 jets
Fuel screws two turns out
Mag side still looks lean..it's light grey.Should I jet that side up one size?

 

[blueblooded]

Going to try 5th position on needle doe mag side.....might go up one size on main jet to see if it looks any better.Im also thinking the 50:1 premix along with oil injection might be why it's running lean.....the fact that it -4 degrees out isn't helping lol

 

[Vincent]

Why are you running 50:1 premix? That's alot of oil on top of what your oil injection is using. Once you switch to streight gas your jetting is going to be different. So you'll need to rejet again. Wrong way to be tuning an engine.

 

[blueblooded]

I'm running 50:1 premix for first tank because it's a new top end rebuild.

 

[A couple of bucks]

I would not make any changes until all of the premix is gone.

 

[blueblooded]

Thanks I'm going to siphon out premix and see where I'm at with straight gas

 

[super1c]

No need to run premix after rebuild. That’s why your lean, too much oil not enough gas too keep things cool. Learned from first hand experience on that one.

 

[A couple of bucks]

Your probably running right now at 20:1.
Not good at all.

 

[blueblooded]

 

[blueblooded]

This is what I found when I pulled the head....this was.a new piston and cylinder.Same thing happened to late one!!!