14mm ve pump

ahale2772 said:
this isnt mystery stuff... its fluid dynamics.
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Great, you understand fluid dynamics. Now, tell me how running a larger orifice injector alters the pressure the injection pump is capable of making.

What you are trying to describe is hydraulic loading, which is the same excuse given to use "large" injectors with the Monster and Dragon Fire VP44. But people know that is a crutch at best, and typically more hp is made with a smaller injector.
 
Even if it doesn't lower the total pressure made by the pump, since there is a minimum required to pop the injector, will it not narrow the amount of time the pump head is exposed to that pressure per stroke?
 
Will the larger orifice alter the time the plunger is energized before it hits spill port? I think the answer is rather obvious.
 
Just checking, they seem to work so they have to be relieving stresses somehow.

I have no idea how timing is controlled in the VP, nor how the pump as a whole compares to the VE. I'll have to look it up before I can comment about any comparisons of them. Seems like apples to oranges, besides the fact that they're both rotary.
 
Tacoclaw said:
Just checking, they seem to work so they have to be relieving stresses somehow.
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We ran a 6x0.016", put 1k street miles on the 14mm head for break in, everything that Brian said to do, made it 70ft down the track before it grenaded.

If I spent the money to build a 14mm VE, I know what I would remove to keep it alive, but blaming the injector size is naive at best.
 
I know there were a few guys even breaking 12mm pumps by spinning over 4K....all I know is that I have big injectors and no "rev-gain" and I can get in my truck and start it up and drive it wherever I want.....that's good enough for me ;)
 
I am over there a fair amount, never saw that post. Lots of info to fish through on that site, and the search results take a long time see all the posts quickly. Specific though
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Yeah, there is a ton of info there, but it’s all buried, and lots of it was "lost" when the site was updated and the search feature was changed (just really hard to find). one guy by the name of "ford571ci" (or something like that) was a big proponent of eliminating the vane pump and running some kind of computer controlled regulator to vary pressure with rpm, but i don’t believe he ever did it. IMO it’s all just a band aid, because the flow will always be limited by the passage to the shut of solenoid. Closing that passage, and letting case pressure regulate timing alone would be the best bet. Then feed the plunger with a separate feed and a high pressure pump (300+ psi) I aim to do this, as soon as money allows me to invest more into a play pump

The problem is you need higher case pressure to force fuel into the plunger via the stock sized rotor inlet. The rotor inlet is smaller than that on a P-pump AND the p-pump allows a longer plunger refill as there are 6 vs 1 on the VE.
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Exactly…

One thing KTA said is that the drop in cc’s he has been seeing with a 14mm head at High rpm might not even be the largest contributor to a drop in power. The fact that it effects timing so much is just as much of an issue.
Say If you go WOT on a 14mm pump , it’s making say 150psi at the vane pump, and you are supplying the inlet with 80psi of fuel, once the case pressure drops due to injector flow, I’m assuming that there has to be some kind of derogatory effect on injection pressures. That how my brain works at least.,Smokem, if you feel differently please explain to me how, I’m honestly curious about it. I understand that it could be getting the same volume of fuel, but its definitely not getting the same MASS of fuel, at high rpm with low case pressure.

question is what is causing the loss in high rpm fueling...

quote from KTA...
The 1st thing I noticed was that the pump needed in excess of 30psi at anything over 1500rpm to keep fueling up, and even then it is falling off bad. At high rpms I am running 80+psi inlet pressure and still cant keep fuel delivery and case pressure up. This is why I think alot of 14mm VE's die. You HAVE TO run a ton of fuel pressure or it essentialy keeps running dry and it scores the plunger. I also tried a 354 spring but even at 4000rpm I didn't gain anything with it. I don't yet know if this is because the pump just cant flow at those speeds yet or if it is governor related.
Flowed with my 6x.018 injectors
RPM Flow Power
1500 460cc 460rwhp
2000 420cc 525rwhp
3000 360cc 677rwhp
3500 320cc 702rwhp
3600 310cc 699rwhp
3800 290cc 690rwhp
4000 250cc 626rwhp
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and another

I think 2 things cause the seizures. #1 to small of an injector to cope with the fuel flow so injection pressures get to high and you distort the barrel and plunger from hydraulic pressure. Since the barrel is thinner in a 14mm since it is a bored out 12mm it more easily distorts. #2 is lack of fuel. If you look at the fuel inlet size in the VE plunger you will see it is very small. By design this hole can not be enlarged and it has to be the same size for a 12mm and a 14mm. This is going to require a special fuel system and some serious reengineering to solve.
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rednsilver90 said:
Smokem, what would YOU do to keep the 14mm alive?
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Im going to guess that after the modifications to make it live and perform, you would basically be left with a crappy p-pump.


14mm heads have been around a long time. Cummins made them work, we should be able to as well.
 
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There were factory Bosch 13mm and 14mm heads. From what I've been told, the 14mm was for a low rpm application. If I personally want more fuel and rpm I'll go P pump. I just wanted to hear Smokem's theory.
 
So what would be a good injector size for the 14mm Weston?

Sent from my rooted Velocity Ally
 
rednsilver90 said:
There were factory Bosch 13mm and 14mm heads. From what I've been told, the 14mm was for a low rpm application. If I personally want more fuel and rpm I'll go P pump. I just wanted to hear Smokem's theory.
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A 13mm head could be cool. Middle of the road kind of deal.

I agree with you though, if my 12mm (which runs great) can't satisfy my fuel and rpm needs I will p pump the truck. BUT, thats what I have a toy for, so I dont need to ruin all the good things about my 1st gen. 400hp in a truck that weighs a measly ~5200lbs WITH me in it is plenty fun on the street, with great manners and little to no money in it (respectively). Not that it makes 400hp now though:hehe:
 
ahale2772 said:
Smokem, if you feel differently please explain to me how, I’m honestly curious about it. I understand that it could be getting the same volume of fuel, but its definitely not getting the same MASS of fuel, at high rpm with low case pressure.
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Very similiar to lack of fill time between cam designs in a P7100. I agree with most of Brian's thoughts except the injector sizing. Line swell and static timing retard have been compared when altering hone sizes and opening pressures, care to guess which had more effect?

rednsilver90 said:
Doesn't sound like he's messed with the 14mm much.
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Your judging this from the fact I have been busy and haven't replied recently?
 
oldestof11 said:
So what would be a good injector size for the 14mm Weston?

Sent from my rooted Velocity Ally
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I doubt he's going to tell you to size for just the H&R, he'll tell you to size for the entire combo you're putting together. (It may not be the best for the H&R, but at that point it'll be up to you to decide your priorities) If I have any reading comprehension at all I think that's what he's getting at with all the sarcastic, vague posts. It would be easier to tell if he just came out and said it though. :shake:

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Apparently through the vagueness and sarcasm you still grasp the concept.
 
Smokem said:
We ran a 6x0.016", put 1k street miles on the 14mm head for break in, everything that Brian said to do, made it 70ft down the track before it grenaded.

If I spent the money to build a 14mm VE, I know what I would remove to keep it alive, but blaming the injector size is naive at best.
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What rpm did you hit?
 
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