Bosch H Series Inline Pump Dynamic Timing

I killed a major thorn in my side last night with regards to my vgt program, and the throttle response is much better. It takes less than fractions of a second to build the boost back that I lose when shifting, to the point where it's not even noticeable. This is exactly what I'm looking for out of my vgt turbo and it makes me extremely excited to see what the future holds for the h pump with twin vgt turbos.

Yes, that's right, twin VGT... I've got a line on a he551 with a gtx4508 billet compressor wheel thanks to BramanteCummins. I'm extremely stoked!
 
Ok, well after joining the bandwagon I've done some digging... The constant pressure DV's are junk lol. They break, clog the injectors then the pump tries to do its job and pressurizes until something breaks, that tends to be the studs on the top of the pump.

Also, the pump is actuated with 0-12v dc. Simple as that. The one on the top of the governor is the timing rack actuator, the thing on the side, fuel shutoff, the rear, fuel rack. The governor control is internal. I'll scan it all in and post it tonight. All the calibration specs and what have you.

Side note, on a 30L engine it will do 1240hp.
 
I can confirm that the constant pressure valves are in fact junk. I swapped out my stockers for them and the little relief valve inside relieves too much line pressure, so when you get to full fuel and up in rpm you actually push less fuel than a stock dv because the volume that should be sent to the cylinder is instead working to repressurize the injection line.
Even if they were set to a different pressure, the reliability of its ability to not bleed off over time, not to mention the reliability of the device structure as a whole like mentioned above is something that pretty much negates any performance gain in the long haul. (daily driving).

Bottom line: if you have them, they're not really worth much.
 
Made some informational progress today.. Looks like the stock h pump cam does in fact have the correct firing order, and quite possibly a quicker plunger ramp rate- meaning it will in theory build higher peak injection pressure and reach that peak faster than a p pump reaches its peak.

That said, we're looking at either a custom gear or machining a stock gear. Either way we're going to end up using the woodruff key slot for extra protection against slippage, since we're looking at increased drive hp needed for this pump at higher injection pressures.

Looking for 5x16 injectors with this setup, and possibly 131/181 hybrid dv's, but not sure on those just yet.
 
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ShadowTrooper said:
Made some informational progress today.. Looks like the stock h pump cam does in fact have the correct firing order, and quite possibly a quicker plunger ramp rate- meaning it will in theory build higher peak injection pressure and reach that peak faster than a p pump reaches its peak.

That said, we're looking at either a custom gear or machining a stock gear. Either way we're going to end up using the woodruff key slot for extra protection against slippage, since we're looking at increased drive hp needed for this pump at higher injection pressures.

Looking for 5x16 injectors with this setup, and possibly 131/181 hybrid dv's, but not sure on those just yet.
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not more pressure, just peak pressure faster. Think of it like a compression ratio ;-)

I still havent had time to go through all that code yet, but soon!
 
CorneliusRox said:
not more pressure, just peak pressure faster. Think of it like a compression ratio ;-)

I still havent had time to go through all that code yet, but soon!
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It could very well build more pressure. Higher injection rate through the same size orifice would require more pressure.
 
It should definitely be interesting.. I hope this is as good as it sounds on paper.. Lol

I'm thinking 5x14 would be better sized for my application, still unsure about dv's
 
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I have a set of moderate delivery valves. The shoulder is .050 and they are worth about 35hp. They were cut with mileage and towing in mind. Let me know if you want them.
 
I love watching builds like this, always interesting to me! I'm curious to see how she'll run!
 
Tate said:
It could very well build more pressure. Higher injection rate through the same size orifice would require more pressure.
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I guess you're right.
I was thinking non-compressible liquid, so it would just make the injectors hit the pop pressure sooner and then relieve pressure. I guess it could be a faster shot, but the same volume as long as the lift doesnt change.
 
StainlessRRA said:
I love watching builds like this, always interesting to me! I'm curious to see how she'll run!
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Agreed! These old suckers with fixed timing keep up with some fast stuff pretty good. Can't imagine what dynamic timing on one could do.
 
YOUNG GUNS15 said:
I have a set of moderate delivery valves. The shoulder is .050 and they are worth about 35hp. They were cut with mileage and towing in mind. Let me know if you want them.
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I will warn you, I'm probably not going to be able to afford them for a while, I can't spend a dime on the truck for at least the next 2-3 months.

This project as a whole is going to take time.. The Chevrolet I have with my current p-pumped 12V is a heaping pile of junk, I bought it off a farm almost 3 years ago and it had already had a rough life. So not only are we talking about the h pump, twin vgt etc, this is all going in a new truck of the same era.
 
Your thread is very interesting to say the least...i have wandered myself how to have variable timing on a 12v. I know that some of the semi's have variable timing, but how many pumps are out there, that have the ability of variable timing and still be able to somewhat easliy adapt to most of our pick-ups?
 
Gambler said:
Your thread is very interesting to say the least...i have wandered myself how to have variable timing on a 12v. I know that some of the semi's have variable timing, but how many pumps are out there, that have the ability of variable timing and still be able to somewhat easliy adapt to most of our pick-ups?
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Unfortunately, it's not as easy as it may seem. The programming being the biggest feat. But hopefully it's worth the frustration and time we put into this.
 
Caterpillar used a pump gear to advance timing. If it could be packaged into our pump gears that'd be pretty awesome.

2010-07-01_044736_Timing_advance.jpg


I think this is different from caterpillars...

edit: duh, says bosch right on it.

Automatic-Timing-Advance.jpg
 
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^the problem with that is drive loading, a 13mm quick rate pump will advance timing faster or slower than a pump that takes less to drive. It would be hard to set one up for many aplications.
 
The whole concept behind this was to do as little adaptation from stock as possible hardware wise. Here, we're looking at moving the bottom 2 mount studs on the timing case and having a gear made or a stock gear made to fit. With a device between the pump and case you start having fitment issues as far as how far back the pump sits and you will need custom lines. Hopefully we can use stock lines with the h pump. Plus with our own electronic control setup it gives us a wider realm of control than a common rail at reduced cost. It is significantly cheaper to buy a new chipkit and flash it than getting a new ecm if we fry something... Plus, we have source code. :D
 
Would it be possible to adapt the pump harness to a vp motor and have the factory ecu control it?
 
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