I've read in some peoples signitures that they have their timing bumped 1.8 is that in reference to the timing dial indicator number.

 

It referrs to distance, just make a mark an bump the pump 1/8 inch towards the engine.

 

What does this really do for you?Just curious

 

The timing is set back from the factory for emission , so many bump it back to a performance level .

 

I am thinking project for tonight. Its time for a little fun.

 

it will also help with egt a tad

 

dont you loose some boost though??

 

Boost will drop a wee bit, but the top end performance out-weighs that. Boost does not always equal power, it just looks cool on a gauge. Try it and if you dont like it, put it back to stock.

 

I'm still wondering what are the risks of running too much timing, and a definitive layman's way of knowing how much is too much, not the "sounds too noisy" method.

 

Ace,

Too much timing causes higher drive pressures. Other than it sounding more 'metallic', the only other thing I can think of is it having a caustic smell. Only an indicator will show what your actual timing is. I've always done mine by ear. Crank it until it sounds raspy and then back off just a hair so it has that typical Cummins beat at idle. Hope this helps you some.

Aloha,
Matt

 

Matt, thanks yes that helps some. I think you mean higher "cylinder" pressures? I was worried because a friend of mine recently burned a piston in his newly rebuilt airplane engine ($$$), he theorizes from advancing the timing too far to control EGT. I think the priciple is the same here.

I was worried because after I did a timing bump last week I noticed an increase in what I think is the metallic sound you mention. Nothing too obvious or (raspy?), but noticeable nonetheless, to me. Now I uderstand the diesels are just natuarlly noisier, but I've always been conditioned to believe mechanical noises emanatnig from engnines are generally speaking, a "bad" thing.

It did seem to run better, like it was spinning a little tighter. But I put it back, because EGT is not an issue for me right now, and I don't want do anything stupid to risk an unnecessary meltdown or other "operator-induced" breakage of some sort.

 

If it starts having a hard time pulling hills, you advanced it to far . ..

 

Ace,

Resistance from the turbo creates drive pressure. It's the pressure in the manifold caused from exhaust heat. The newer, larger exhaust turbine wheels (71mm) have lower drive pressures due to increased diameter and design in blade pitch.

Aloha,
Matt

 

With my bump in timing, I never really caught on to a metallic sound. I will say that she pulls like a ***** on the only hill here. Where I have lost out is the bottom end grunt, she's wanting a little more fuel to get going in second. I can appreciate your caution ACE because I was frightened at what harm rotating the fuel pin was causing....these engines are very forgiving.

 

I shoved mine all the way to the head and the only time I get the 6.2l sound is on startup. I figure thatis because the ksb advances the timing a bit at start-up so I kept it there. Egts are under control a she runs good and hard