12v Tuning advice

from the info I have, it is supposed to be pin timed at 25*, I have it set at 30*. I was contemplating bumping it to 34*? But I’m not sure how far to push it. Stock pistons, 145* cone on the injectors, thin washers. I could pull the comp cuts and install my 7mm’s but I almost feel that would be counter productive.
 
mtm94ramnasty said:
from the info I have, it is supposed to be pin timed at 25*, I have it set at 30*. I was contemplating bumping it to 34*? But I’m not sure how far to push it. Stock pistons, 145* cone on the injectors, thin washers. I could pull the comp cuts and install my 7mm’s but I almost feel that would be counter productive.
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It would be interesting to put a timing light on it to see where it's actually at. I think somebody makes a diesel adapter. That's how we figured out the timing on my first gen was all wonky. It was skipped a tooth, but in the wrong direction! Made EGT crazy hot too.
 
I'd time it off of port closure on the pump, less guess work and even if it isn't dead accurate it's a good reference point if you set timing that way every time.

What's the exhaust look like going down the track? You'll likely lose a little fuel going to the 7mms but not a ton, being a 12mm pump it shouldn't make a huge difference either way.
 
zachu812 said:
I'd time it off of port closure on the pump, less guess work and even if it isn't dead accurate it's a good reference point if you set timing that way every time.

What's the exhaust look like going down the track? You'll likely lose a little fuel going to the 7mms but not a ton, being a 12mm pump it shouldn't make a huge difference either way.
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Lift port closure is supposed to be 3.70, and you add .2mm for every 1* of timing? If that is true then I should use 9.7mm for 30*? The chart I have says 9.1mm for 30* which is where I have it set at now.
 
I'm not a big fan of that method, I've got my pump cam all mapped out and I still don't quite trust it. I like to pull out the DV holder and DV then look into the number one barrel. When the plunger completely covers the fill port that's my reference point for the start of injection. Once I have the pump where I want it I'll rotate the engine backwards however many degrees of timing I want.
 
zachu812 said:
I'm not a big fan of that method, I've got my pump cam all mapped out and I still don't quite trust it. I like to pull out the DV holder and DV then look into the number one barrel. When the plunger completely covers the fill port that's my reference point for the start of injection. Once I have the pump where I want it I'll rotate the engine backwards however many degrees of timing I want.
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I’m going to have to give this method a try. Purchased the pdd degree wheel. I did how ever play with the timing a little bit. I stuck to my chart for now. I tried advancing the timing up to 34*. Truck seemed to have lost midrange, but seemed to pull harder above 3500 rpm. Boost went down, smoke staid the same, egts staid the same. Lowered the timing to 28* egts actually went down 50-100*, boost went up 6psi from 34*s smoke was the same. Truck felt very strong in midrange, about the same top end. It was hard to tell because I burst another intercooler boot. I expected all of the above except reduction of egt lowering the timing and topend feeling the same with the lower timing.

I’m wondering with a stock 12v piston even with the 145* injectors, thin washers, and .010 over headgasket maybe 30* is too much timing?
 
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mtm94ramnasty said:
I’m going to have to give this method a try. Purchased the pdd degree wheel. I did how ever play with the timing a little bit. I stuck to my chart for now. I tried advancing the timing up to 34*. Truck seemed to have lost midrange, but seemed to pull harder above 3500 rpm. Boost went down, smoke staid the same, egts staid the same. Lowered the timing to 28* egts actually went down 50-100*, boost went up 6psi from 34*s smoke was the same. Truck felt very strong in midrange, about the same top end. It was hard to tell because I burst another intercooler boot. I expected all of the above except reduction of egt lowering the timing and topend feeling the same with the lower timing.

I’m wondering with a stock 12v piston even with the 145* injectors, thin washers, and .010 over headgasket maybe 30* is too much timing?
Click to expand...



I would spend a little more time on the timing part before a pump change. I think personally, especially with a .010 over head gasket your timing is to high. I have a 2v engine making 770hp with 369/480 setup and 160 pump at 440cc fuel with 5x18. He is wide bowl piston and injector setup.

I typically see 5*18 145* run the best at 24*/23* timing, and scale the fueling back till its clean, then add a little bit more to bring EGTs down. I think you way overkill on the fuel side for that setup.

Im bringing the same truck as described above back on the dyno to test, same fuel setup but just gunna mess with timing again and went to a 372/488sxe twin set up. Hoping to be 850-900hp with a 440cc pump by Farrell Diesel.

Let me know if you ever wanna some testing on the dyno for a Sunday or Saturday. You are not to far I believe.
 
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