Why does FP recommend such different jettings.

[B-Roy]

From the Limited To the Mod Pipe.

On a stock ski, with a B-Pipe Mod. I am told to run 135, 75. This is not what FP recommends. But I was just curious on why they recommend such a large difference.

 

[Matt_E]

I have found FPP's jetting specs to be pretty accurate. That's just me though.

 

[hangtime]

Stock ski with a mod pipe doesn't make sense .
Obviously you get the most gains by having a modified engine.

 

[B-Roy]

Thats what I was wondering about.

The only thing I came up with, is the mod pipe maybe theyre assuming you are running a single carb instead of Twin?

 

[Matt_E]

There are three SJ instructions on their site.

"701 Superjet Mod" assumes a single 44SBN carb, so that would be the pre-96 engine (61x/61x)

"701 Ltd. up to 1995" - that's pretty clear

"701 Ltd 1996+" is for post 96 engines (62T/61X) with dual 38's.

There are no instructions for the Mod chamber on a 96+ engine. Simply use the Ltd. instructions.

 

[B-Roy]

That makes perfect sense.

 

[GIL]

I went thru the exact same thought process-broke down and called the god of horsepower-Paul-75 pilots-low speed screws 1 turn out/135 mains-high speed screws 1.5 turns out/stock needle and seats and springs.

 

[FLY6584]

I went thru the exact same thought process-broke down and called the god of horsepower-Paul-75 pilots-low speed screws 1 turn out/135 mains-high speed screws 1.5 turns out/stock needle and seats and springs.

I'm pretty sure you need to run 95g(dull silver) springs also. Not all SJ's came with 95g springs either. Later one's like my 03 came with 115g springs(gold).

 

[yamanube]

I sent an inquiry to FPP trying to get some info on jetting for my Typ4, I have to say their customer support kind of sucks. First they told me because I am running an ADA head he couldn't offer me jetting suggestions then when I asked him if the jetting information on their site for the superjet "dry pipe" is for a type4 or other he said "there is only one pipe called 701 superjet dry" and has not responded to me since.