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Discussion Starter · #1 ·
so i have searched the forums and google, and i can't quite grasp what extra timing does when added on tuners such as a smarty :confused013:.. can someone please enlighten me? thanks a ton!
 

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Diesel sniffer
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Fuel injected sooner causes it to burn for longer in the cylinder maximizing efficiency. There's a limit though as too much causes timing rattle, not a good thing.
 

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Discussion Starter · #3 ·
ok so every time some says about moving up timing 1 or 2 or whatever, that means that the fuel injection is kicking in sooner.. but if its to soon id imagine there is a build up of fuel, which isn't good causing this "timing rattle" ? thanks!
 

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Diesel sniffer
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Yes, the timing rattle is caused by the fuel igniting before the piston has reached top dead center. This usually only happens at low rpm like under 2000. Once the engine is spinning that extra timing is OK.
 

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Discussion Starter · #5 ·
ahh i see, so it causes almost a mini explosion instead of a nice solid burn. one last question and it should be cleared up, why does the speed of the engine matter? because the piston reaches tdc quicker or what? thanks a ton for helping me
 

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Diesel sniffer
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I'm not sure of the physics of it, but as the piston speed gets up there it's much less of an issue. I've only had it once when I was in overdrive at low rpm and pressed the throttle but not far enough for a downshift, and it sounded REALLY bad!
 

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Discussion Starter · #7 ·
lol alright thanks!
 

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And dont forget about putting the valve through your piston if you add too much!
I doubt it will let it happen, but its just a thought!
 

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And dont forget about putting the valve through your piston if you add too much!
I doubt it will let it happen, but its just a thought!
That would only be true if he were timing a cam, the OP is talking about injection timing
 
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heres timing for ya.. In an Ideal world these trucks shoud have a timing curve.. At lower rpms, you cant run as much timing. Believe it or not, but more timing actually takes away torque. Timing is for higher rpms more so than low end grunt. Whenever we advance timing on our race engines here at work the torque may stay the same or fall off some but we usually..usually gain some hp. Too much timing at lower rpms causes alot of cylinder pressure and heat inside the engine. This would be a bad situation as it could melt a piston. As the rpms speed up the piston is traveling faster as the burn rate stays the same, so even tho you have added timing and it is firing maybe .060 in the hole or so, the piston is traveling up the cylinder quick enough that it doesnt try stoping the piston in its tracks.. I wish smarty would list ok guys 1 is this much timing, 2 is this, etc..
 

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Discussion Starter · #11 ·
ok thats what my understanding was, that the speed of the piston makes up for the earlier timing.. and yea timing is usually in degrees correct?
 
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