VP Dynamic Timing Vs. Advancing

BrettWINspeed said:
One thing I just thought about is could 1 tooth actually equal 10* or 2.5*? Pump speed is equal to 1/2 engine speed.
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now quite sure on that one but my guess would be 2.5 instead of 5 but not 10. if it was 10* off i think the ecm would pick up on the difference and go into limp mode.

sstockton, the advance cam timing is awesome, made spool up even quicker even when i was running a stock cam, and i have used it on most cams out on the market in many different trucks.
 
Yeah, it seems like it would be closer to 2.5*.

Where do you get the Cam timing advance keyways? I'm running a helix2 and would love to give it a shot.

Brett, I sent Eric a PM on Norcal. I have a few things I would like to do to the truck first. But that should all be done in short order here. We can get this figured out, and come up with some good ways to test it. I'd like to test with the box on and off. Also test with the box run as a timing only box as well.
Sean
 
You might be able to get the keyways from Cummins, I wonder if they have listings for the cam and vp keyways to see if they are interchangable. If they are interchangable you should be able to get them from diamond diesel or the pump shop up near TPD in Santa Rosa.

I'll talk to Erik and Adam about it next week to see if we can help you out since we've always wondered wether it will work.
 
I'll give the shop down the street from Drake a call and see what they say. I need to run some injectors in there, and have the pop pressures set too, unless thats something you guys are able to do.
Sean
 
Ok, so it actually seems like 5* degrees advance on the pump gear would equal 10* on the crank. Each tooth on the crank equals 10*. And you are changing tooth position by 1 tooth. So you are advancing the pump shaft 5* but injection but 10* in relation to the crankshaft. So it seems like 1 tooth is probably about all you would want to advance.
Sean
 
sstockton said:
Ok, so it actually seems like 5* degrees advance on the pump gear would equal 10* on the crank. Each tooth on the crank equals 10*. And you are changing tooth position by 1 tooth. So you are advancing the pump shaft 5* but injection but 10* in relation to the crankshaft. So it seems like 1 tooth is probably about all you would want to advance.
Sean
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no. its 2.5*, not 10*.

the crank goes around once, the pump goes around 1/2 revolution. 70 teeth divided by 360* is 5* per revolution of the pump. which is 5* every TWO revs of the crank. 2.5* per single rev.
 
Rollin Coal said:
no. its 2.5*, not 10*.

the crank goes around once, the pump goes around 1/2 revolution. 70 teeth divided by 360* is 5* per revolution of the pump. which is 5* every TWO revs of the crank. 2.5* per single rev.
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I'm still thinking 10* because in the time it takes the VP to rotate 360* the crank has rotated 720*, thats twice as much rotation. So if the VP rotates 5* then the crack has rotated 10*.

Phily 911 said:
Any fault codes? This is interesting.
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Nope, no fault codes. We'll see if it makes any gains in power on the dyno.
The truck seems to run great.
Sean
 
24VCummns98 said:
so would it be possible at all to have the timing stay at one certain degree??
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I believe that is more commonly referred to as a p-pump swap...

Anything is possible if you can hack your way into the pump control module electronically and figure out what signal does what.
 
Rollin Coal said:
the only down fall to a p pump is the fixed timing...... why add another fault to a vp44?
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I agree with you there. I've actually been wondering about the feasibility of having a strictly RPM based dynamic timing set up for a p-pump. It would be pretty tricky, requiring a new front cover for sure, but it should be possible.
Sean
 
some one could make up a pump gear with weights that move and advance timing based on RPM, probably wouldnt be all that hard either, now to find some one with a bunch of money and a good machine shop with some spare time
 
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heck yeah. mercedes had that one down years ago.. 2 cams per head and plus or minus 30 degrees for each cam independently of the other 3.. crazy flat torque off idle and any rpm you want. applied to a vp and you can spool a huge turbo with backed up timing then gain your power like crazy.
 
well some one hurry and come up with something. I could have used it today to get the turbo lit on the rollers
 
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