Howdy,

I turned my governor screw out a little ways after I installed the tach and now I get 3400rpms before it defuels...

What would be the advantage to changing-out the governor spring at this point? Should I ?

Will it add more fuel besides just upping the RPM's(which I already have)?

Thanks,

Vinny

 

How are you checking your engine defueling? Best way is to put it in 2nd gear with an auto/3rd gear in a manual and get a nice stretch of road and see what your rpms are. 3400 is pretty high with just high idle adjustments. Just punching it in neutral would probably get those kind of numbers but this is not really checking to see where your pump defuels.

Carl

 

Yup,

That's what I'm doin...2nd,3rd,4th...take your pick...I'm gettin' 3400rpms(tach has been calibrated with an optic tach).

Before I touched the screw,or installed the tach,it would do 72mph in 4th.

Maybe it already has the governor spring in it?

But it still had the collar on the full fuel screw...and it didn't hardly smoke at all before I turned-up the FF screw.

Should I turn it back down a little?

Vinny

 

What we mean by defueling is the point where the engine seems to "lay down" and not pull so hard. The defueling point is at a lower RPM than max governed RPM, which in your case is 3400 RPM. You're probably defueling by 2800 RPM. The 3200 RPM spring will keep the engine pulling hard to 3200 RPM.

 

Wannadiesel,

I don't really feel it lose power on the way up...

Before I put the straight pipe on,it used to spin the tires in third when the boost came on...now it doesn't.

It seems to just pull the same all the way up to about 3000 RPM's...but even then it doesn't really "nose over" on it's way to 3400...

Vinny

 

I don't think you've got the 3200 RPM spring in there, if you did it would keep pulling hard past 3000 RPM. When these trucks defuel it's not like you stop accelerating, they just don't pull quite so hard. As long as your EGT is under control, go ahead and turn it up some more, then your tires will spin.