Excessive timing with vp, can it hurt?

cummins724

cummins724

BREAKING $HIT
Joined
Apr 16, 2007
Messages
8,568
I recently talked to Chip at Blue Chips Diesel & asked him about timing vs. high rpm. Chip said "you can't get too much timing from a vp44". I asked "well, what If I turn my Adrenaline & Smarty to max timing?" He replied "The timing advance is limited within the vp44 injection pump & it can only be altered to a point." According to him, we can't get enough timing from a vp44 to take the spray pattern of the injector outside of the bowl, unless ofcourse a wrong spray pattern was present from the start. Thoughts?
 
Weston has said that he has seen an HO with just an EZ spray out of the bowl. I myself haven't seen one out yet!! Would be nice to find out how far it is actually taken???
 
I had my truck on John's dyno back when it had a vp44 and Marco himself was altering the smarty settings between runs. We tried more timing but couldn't get any more power out of it or any more hp farther up the rpm. 593hp 1340 tq Granted every setup is different...
 
From what I've learned lately the timing advance is controlled in the VP44 buy a piston that reads off fuel pressure. I would guess that maximum timing would occur when the ECM calls the pump to adjust to maximum timing and the advance piston is at its max position. As the pump wears the timing will gradually and ever so slightly reduce until the piston wears to the point where the fuel goes around it and you have no advance. This is why the rebuilt pumps have stainless sleeves on the pistons because the factory pumps were not sleeved and the castings wear out. That is what I've learned, hopefully it is accurate and adds some info to this thread. :D
 
You VP guys need to just advance it on the gear. Worked wonders with my CP3. LOL




Sorry. Going back to my corner now...
 
Hey Amish, just thought I would bring you up to speed on how the new twin cp3s are now being timed....one gets timed for early injection and one for late injection....that's how they get multiple injection events....the more cp3 pumps you add, the more injection events that can be added. Makes sense don't it?




Don't try this at home!!:hehe:
 
if the vp44 does its timing internally with electronics, could it still be fooled but advancing the shaft of the vp with the gear via machining a new keyway slot in the shaft or gear? i dont know the inner workings of a vp44 but is the rotor of the pump somehow connected to the shaft to where it would make a difference, if the pump shaft was advanced in relation to the crank position.

just thinking out loud here, like i said i dont know exactly how the vp44 works so this may be a dumb thought too.
 
From memory the VP has and internal sensor that lets it compensate for the timing. IIRC it can be a tooth off and still set the timing.

I guess you would have to maching the stator or what ever its called over X degrees to what you want to advance too.
 
I had timing cranked as far as it could go for fuel mileage tune I was trying.

Everything was fine and dandy till I started going up a small grade. I'm sure it probably was within "spec," but I didn't like how the engine sounded!! I backed it down, and haven't run that much again.

My injector spray pattern is outside the bowl, but I'm attributing that to crummy Jammer injectors. When funds allow, I'll get a new set.
headgasket8.jpg
 
I set my Smarty to max timing & Adrenaline to max timing [new 4k box] & I revved it up to 4300 or so, let off of it & the engine stayed revved for a minute, then slowly came down to idle...just like a CR does. With the old ADR box & 70% tune, I run max timing & that doesn't happen. It stays very strong the entire way & rips azz! I've been experimenting with more pressure & max timing etc. Truck definately runs the best with all timing maxed. I want to figure this out before we head to the dyno next time.
 
I'm struggling to remember the details, but I think you could pull the cam and modify the tone ring mounted on the back side (oval the mounting holes, and rotate it) to trick the ECM into thinking there was less timing than normal so it would compensate. Something along those lines...
 
so why when you stack two timing boxes does it sound like the truck is gonna come apart? fuel press?

and the sensor that compensates off fuel press., is that LP or IP?
 
Mudn_1 said:
so why when you stack two timing boxes does it sound like the truck is gonna come apart? fuel press?

and the sensor that compensates off fuel press., is that LP or IP?
Click to expand...

I guess you need to try 2 timing products which work together doing different ways. The Smarty & Adrenaline timing seems to work very well together from what I've seen. I would love to take a look in my cylinders with a scope to see what they look like, but I bet they are still in the bowl pretty well. I have tried multiple settings now to see if I can feel the power drop off...telling me I'm over timed, notta yet. Ofcourse I'm referring to the standard ADR box, 4k box doesn't seem to play to well with max timing.
 
getblown5.9 said:
if the vp44 does its timing internally with electronics, could it still be fooled but advancing the shaft of the vp with the gear via machining a new keyway slot in the shaft or gear? i dont know the inner workings of a vp44 but is the rotor of the pump somehow connected to the shaft to where it would make a difference, if the pump shaft was advanced in relation to the crank position.

just thinking out loud here, like i said i dont know exactly how the vp44 works so this may be a dumb thought too.
Click to expand...

hence the offset key.:poke:
 
I remember reading a thread on DTR about a guy in Texas who was running a superchips programmer and a Edge EZ or a Van Aken, or some other similar box towing heavy and ended up with a blown head gasket and melted piston crowns. From the pictures, it was obvious that the injectors were spraying out of the bowl.

I don't know enough about VP-44's to know for certain the maximum mechanical limits of the pump to advance timing but if I recall correctly, the pump is capable of spraying outside the piston bowls.

If power does not drop off, you'd have to assume that most of the fuel is staying in the bowl and that the extra power is from the more efficient use of the previously late fueling ie pump stretch.
 
These are pics of my 01 HO motor after running an edge ez for approx 40k miles,stock injectors,no other tuners,boxxes.My question is are the patterns on the top of the pistons from spraying outside the bowl?
DSC00429.jpg

DSC00430.jpg
 
You must log in or register to reply here.
Back
Top