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So im gonna be gettin a 24v soon hopefully and i have a p-pump laying around off my pulling truck and i got two questions do i have to repop the ijectors or is it ok to kkep them set a vp pressures? and second what did you guys pay for your p-pump conversion kit whats the cheapest around?
 

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There are a lot of guys running VP44 injectors with a p-pump. It's not the best set-up, but it works. As for the cheapest kit, look for a complete donor engine and grab what you need from it. You'll still need to buy the lines, though.
 

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290-300bar is what worked best for me. Higher pop pressures make for better atomization.
 

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What injectors??? with my p-pump??

im gonna be doin my p-pump conversion?? i kno if i keep the stock 24v injectors i have to reset the pop pressure but wat are some better routes to take?? bc i dont kno wat i should runn?
p.s im having my pump built with 191 dv's or bigger and 4gsk the pump is a 160hp.

thanks mike
 

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For the conversion kit, this is best for the money
P-Pump Conversion Kit
thats a really neat kit...really reminds me of something turbolvr built...looking at that kit it comes with his tunnel ram intake, instructions to use the 24v apps which he kinda came up with...well done kit! it can be done cheaper but you get everything you need to do the swap...that is turbo's kit! :thumbsup: whats the deal with the vacuum pump kit?
 

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Vacuum pump kit was added as a "while you're in there" bonus. The vac pump is NO fun to do after the swap, so if you have a weepy seal or just want to be sure you dont have to do it later, its included.
APPS bracket in the pic was a prototype. They are all billet now.:thumbsup:
 

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Vacuum pump kit was added as a "while you're in there" bonus. The vac pump is NO fun to do after the swap, so if you have a weepy seal or just want to be sure you dont have to do it later, its included.
APPS bracket in the pic was a prototype. They are all billet now.:thumbsup:
very well dont kit turbo! :thumbsup: ya thats funny because something in that area is leaking oil on my truck...and im going to be pulling both of them to get it fixed and dryed up when the weather gets warm. it leaks a good bit of oil and there is three things that could be leaking in the area, the ip, tappet cover and vacuum pump so yep i will be experiencing that first hand. btw i am really impressed with you p24v intake plate and i think i am going to be geting one of those as soon as i can. and your making a billet 24v apps bracket? i would really like to go back to the apps but im all set up with the 12v tps so i dont know if there is a benefit of switching back?
 

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If you have already converted, no reason to swap if you have it dialed. The main advantage was to not have to swap all the cables/linkage and splice wires, just bolt and go.

kwilks27- injector pops are lower on the Ppump usually about 280bar where the VP is 305bar. The injector pressure affects timing as well as total fueling (how long the injector is open).
 

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If you have already converted, no reason to swap if you have it dialed. The main advantage was to not have to swap all the cables/linkage and splice wires, just bolt and go.

kwilks27- injector pops are lower on the Ppump usually about 280bar where the VP is 305bar. The injector pressure affects timing as well as total fueling (how long the injector is open).
thats one thing i have been meaning to ask is how much does the pressure affect timing? i was told 10 bar is about 1* of retarded timing...does that sound right? so if 12v pop is 260bar then 300 bar would be 4* of retarded timing meaning that i'm only siting at 14.5* instead of 18.5* that my pump is pinned at.
 

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That sounds about right. the lines & tubes ID also has an affect as the larger volume allows more compression and breathing of the lines (one reason the more rigid SS lines are used for racing where accurate timing is essential) adds to the retarding of timing.
The spray angle of the injector is also wrong for a Ppump as it is tuned for lower emissions when combined with a pump that runs higher pressure and dynamic timing.
The VP uses a short burst and high pressure to deliver fuel accurately into the bowl, the P7100 uses a longer duration lower pressure spray with static timing that the 24v was not designed for.
Most 24v daily driven 12mm Ppumped trucks are timed in the 20-24* range.
 

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thanks for that info turbo. ya i am going to be turning my timing up to about 24* but im a little concerned that i still have the stock headbolts and i just dont want to blow anything but i want to get the timing up for performance and economy not to mention how much fuel im dumping down the exhaust because i dont have enough air and the timing being at 14.5* after overcoming the 300bar. i know i need studs but im a little short on cash right now after buying new tires and 2 new conversion lines...
 

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BE CAREFUL! bring it up to 20* and see how it runs. you DONT want to make it too high. You're better off with too little than too much. find & mark TDC as accurately as you can and set the timing @ 16* then go up 1-2 degrees at a time. you'll feel the powerband move up the RPM scale as you advance it. Too much timing will get you out of the bowl and delay starts blow headgaskets and cause a lot of grey smoke as it sprays fuel past the rings and you will lose bottom end and spooling as the fuel burns too early putting a tremendous load on the crank/rods and HG. Use baby steps and dial it in.
 

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BE CAREFUL! bring it up to 20* and see how it runs. you DONT want to make it too high. You're better off with too little than too much. find & mark TDC as accurately as you can and set the timing @ 16* then go up 1-2 degrees at a time. you'll feel the powerband move up the RPM scale as you advance it. Too much timing will get you out of the bowl and delay starts blow headgaskets and cause a lot of grey smoke as it sprays fuel past the rings and you will lose bottom end and spooling as the fuel burns too early putting a tremendous load on the crank/rods and HG. Use baby steps and dial it in.
ya my pump is pinned at 18.5 now and i have the tdc pin but i dont really know how accurate it is because it's referenced off the cam gear which is just two dots lined up. i really want to drop a valve and use a dial indicator to find absolute tdc. thanks for the advice man. i have a friend that sold his truck and he was running a he351 over s475 with 240hp vp injectors still at 300 bar with a 160 pump on retorqued headbolts at 24* and i dont think he blew anything but he couldent make more than 55psi without blowing a tube off the secondary. 24* at the pump will come out to about 20* at the injector which is why i was thinking that number and i have been told that the p24v loves timing...as long as it's still in the bowl. and i thought that you needed about 25* at the injector to get out of the bowl? that is with stock spray angle injectors. is that correct or am i wrong on that?
 

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It also depends if you have an SO or HO and if you have stock thickness gasket and injector washers and if the head has ever been decked, or pistons cut.

ANY change in distance from the injector tip to the piston bowl will affect timing and must be adjusted for.

Quality and accuracy of injector design and pop pressures, temperature of air/fuel, size/type of DVs, connector tubes ID w/wo edge filters, mild or SS lines, ect. All these things must be accounted for if you want to get the most & best performance.



...and you thought it was easy!:rof
 

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It also depends if you have an SO or HO and if you have stock thickness gasket and injector washers and if the head has ever been decked.
ANY change in distance from the injector tip to the piston bowl will affect timing and must be adjusted for.
ohh ya i remember the HO's...:hehe: being a different angle. mine are SO 300bar stage 4 Diesel dynamics injectors which are about a 150hp vp injector. my truck was mostly stock when i got it, head and block have not been touched and the stock hg is still in use.
 
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