JSP's Triples via GTX4508's/Tial stainless housings.

dvst8r said:
Was 1268 uncorrected at 1750us, for you 12v guys that 1750us doesn't mean anything to, there is good fuel until at least 2500us.
Click to expand...

But it does when you put it into simple terms;

1750µs @ 2000RPM = 21° injection window
2500µs @ 2000RPM = 30° injection window

Problem is those numbers double @ 4000RPM, and this is where the CR nozzles are falling short. The big mechanical injectors are able to overcome this for one very good reason, and it has nothing to do with the holder/body.
 
Smokem said:
But it does when you put it into simple terms;



1750µs @ 2000RPM = 21° injection window

2500µs @ 2000RPM = 30° injection window



Problem is those numbers double @ 4000RPM, and this is where the CR nozzles are falling short. The big mechanical injectors are able to overcome this for one very good reason, and it has nothing to do with the holder/body.
Click to expand...


What is the reason they are able to
Overcome it? Is this what's going to be the big limiter with cr stuff


Sent from my iPhone using Tapatalk
 
Smokem said:
But it does when you put it into simple terms;

1750µs @ 2000RPM = 21° injection window
2500µs @ 2000RPM = 30° injection window

Problem is those numbers double @ 4000RPM, and this is where the CR nozzles are falling short. The big mechanical injectors are able to overcome this for one very good reason, and it has nothing to do with the holder/body.
Click to expand...
You beat me to it. If you're quoting around 1000us, then you're talking my language. 2500us is great for breaking parts with staggering amounts of torque, but until you're able to put all that fuel in a sub 1000us window and move the HP up the RPM band, mechanical still wins.

All that to say the build looks awesome Mr. JSP!
 
97rada said:
What is the reason they are able to
Overcome it? Is this what's going to be the big limiter with cr stuff


Sent from my iPhone using Tapatalk
Click to expand...
This is how I understand it and I could be wrong but basicaly at 4000rpm the engine will rotate 42* for the injection event, a mechanical engine will remain the same due to the crank directly driving the injection pump. So the engine spins faster but the injection event takes the same amount of time, where on the mechanical engines the injection event is in direct connection to the crank so it speeds up as well.

Love the build Om nom nom nom nom
 
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joefarmer said:
You beat me to it. If you're quoting around 1000us, then you're talking my language. 2500us is great for breaking parts with staggering amounts of torque, but until you're able to put all that fuel in a sub 1000us window and move the HP up the RPM band, mechanical still wins.

All that to say the build looks awesome Mr. JSP!
Click to expand...


I should clarify that's the sum of electrical time, this is my old set of injectors and its over 600us of latency before the hydraulic injection.
So about ~1150us actual injection time.

Agree though, only thing that will be holding this thing back is injector.
 
On a mechanical pump engine the injector opens and closes purely on pressure. So as the pressures rises and falls so does injector opening/closing. As engine speed increases the amount of time that the pressure is raised gets shorter too. So it's not all that different in having issues that have to be over-come.
 
Some of you might remember this dyno chart from back when I had my s480/64 compounds....pretty stout for a 80mm.

HamiltonVSStocker.jpg



But DAMN.....looks pretty weak compared to the triples! I wish I swept lower to see just where it crosses the old pulls.

Twinsvstriples_zpsaf93e29c.png


Changed the oil and adding fuel.....
 
God this is an amazing build. I just hope you don't have to change any parts, you couldn't fit a childs hand into that engine compartment:)
 
Looking good so far, can't wait to see the numbers when you really add some fuel.
 
Whats the harm in energizing the armature to just the brink of an injection event to reduce latency? Im not sure what all conditions exist and it may be foolish or my misunderstanding.

Monkey Fist Rage
 
biggy238 said:
Whats the harm in energizing the armature to just the brink of an injection event to reduce latency? Im not sure what all conditions exist and it may be foolish or my misunderstanding.

Monkey Fist Rage
Click to expand...


I doubt any current ECU's would be able to do it, but something like nira that's been modified/design changed with capacitors fit for a higher duty cycle.
 
biggy238 said:
Whats the harm in energizing the armature to just the brink of an injection event to reduce latency? Im not sure what all conditions exist and it may be foolish or my misunderstanding.

Monkey Fist Rage
Click to expand...

In reality that is what is hapening, electrical timing is in advance of the hydraulic actuation. So there is a latency from initial injection pulse to excite the solenoid to open the control chamber. This time is simply taken up with advance. Now the next delay is actual pintle movement and this is a function of inertia and the time it takes to bleed down the control chamber with a function of pressure.

Now I seem some SAE data that showed pintle movement in a mechanical injector being almost double the speed of even the newest generation piezo injector. Frankly that blows. A true piezo full stack injector could be a real animal if someone was to take on the engineering to do it. I think Denso has one but likely could not drive the nozzles we need. Some rough math figured out that they would need to be a foot long.
 
Great thread keep the i no coming. How are you findig the tial housings effect initial spool up? I have used them in other none diesel apps and found little to no difference over a dual entry.
 
CurtisEmery said:
Great thread keep the i no coming. How are you findig the tial housings effect initial spool up? I have used them in other none diesel apps and found little to no difference over a dual entry.
Click to expand...


I can't really say, as I never ran these chargers any other way, but I do feel that the tubular manifold does hurt spool considerably, but when they do come its like a light switch. I think my 96mm 1.32 s480 would actually out boost it in the lower rpms.....need to compare some pulls as a single.

As to top end power they are great though, the thing just wants to run away. Torrey's running a single volute housing as well and we were really surprised how well it spooled.


Here's a vid of this run......I'll try and make some more, was planning on a incab vid at the same time. It's just about cleaning right up. Even the calculated A/F the ECM is doing is showing it's looking for fuel.

[ame="http://www.youtube.com/watch?v=XzTxZACkG0E"]http://www.youtube.com/watch?v=XzTxZACkG0E[/ame]
 
Its sickening quiet actually.....if turbo noise is your thing don't go with the GTX's! The superdave would scream so loud the camera sound would just clip if you were to close.
Maybe if I juice them it'll make some noise....LOL
 
Incredible. Have you driven it on the street yet? How much boost are you seeing on that run in the video?
 
The boost is on the chart X10 so 1111 is 111psi. Haven't been on the street yet but imagine its something stupid.
 
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