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injectors

OP
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Thread Starter #2
what is the big secret about the injectors?someone has to know
 


Spaceman_Spiff

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#3
Yeah, seems to be a highly guarded secret. I can find part numbers, but no where does it list specs for any of them. Best I could find is this quote for an aftermarket injector:
Fuel Injector

We found Deatsch Werks’ booth with a strange looking fuel injector on the display. It’s their new direct-injector for EcoBoost applications, standing up on a long, thin nozzle compared to the typical stubby port-style injectors. These are a cost effective solution for $640, not much more than equivalent port injectors, Their new HDEV1700 direct-injector, capable of flowing 1,700 cc. DW says the HDEV1700s are good for 30 percent more volume than the stock injector, meaning that fuels like E85 can be used, although the high-pressure pump is still a bottle neck…
I guess it flows 30% less than 1700cc?
 


JDG

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#4
Yeah, seems to be a highly guarded secret. I can find part numbers, but no where does it list specs for any of them. Best I could find is this quote for an aftermarket injector:


I guess it flows 30% less than 1700cc?
23% less you mean?

From the info you quoted, the stock injectors likely flow ~ 1300 cc
 


Spaceman_Spiff

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#5
23% less you mean?
[scratch] eh... I must have missed something, I don't see where you get 23%. They said their aftermarket injector flows 30% more than stock. Either way, it's not a hard figure on the stock flow rates. It was the best I could find on it.
 


OP
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Thread Starter #7
thanks to all for the info.wonder if stratified or russ would know?
 


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Austin
#8
Interesting. 1000cc port injection can sustain like 400 HP, wonder why 1300cc DI cant keep up
 


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Roseville
#9
[scratch] eh... I must have missed something, I don't see where you get 23%. They said their aftermarket injector flows 30% more than stock. Either way, it's not a hard figure on the stock flow rates. It was the best I could find on it.
1700 is about 30% more than 1300
1300 is about 23% less than 1700

That's where the 23% comes from.

Cheers
 


jeffreylyon

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#10
Yeah, seems to be a highly guarded secret. I can find part numbers, but no where does it list specs for any of them. Best I could find is this quote for an aftermarket injector:


I guess it flows 30% less than 1700cc?
I looked at the Deatsch Werks site. The 1700cc injectors are listed for use on a Focus ST or RS.
 


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Thornton
#11
Interesting. 1000cc port injection can sustain like 400 HP, wonder why 1300cc DI cant keep up
Because that 1000cc injector has 720 crank degrees to deliver the fueling needed for the engine. A DI injector has roughly 270 degrees of crank rotation to deliver the required fuel.
 


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#13
This even more demonstrates the difference, thanks for the data. So only 31% of the time available for a DI injector vs a port injector.
 


jeffreylyon

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#14
This even more demonstrates the difference, thanks for the data. So only 31% of the time available for a DI injector vs a port injector.
Exactly..., does that mean that a more aggressive cam with a longer intake duration will let us squeeze more out of the stock injectors? We've got something like a 300HP limit with the stock injectors. I've heard that is due to the HPFP and I've heard that is due to injector flow. If our limit is due to injector flow and not the HPFP perhaps a cam with a longer intake duration will allow the injectors to flow longer, increasing the 300HP limit?
 


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#15
Oh I see, you're referring to the intake cam duration. The DI injectors will continue to spray into the compression stroke until the required fuel is met. If you need more fueling than that, you'll need a custom camshaft made with 4 HPFP drive lobes vs 3. That's the difference in fueling from the FoST and FoRS. The ST has 3 lobes, the RS has 4. They use the same HPFP.
 


jeffreylyon

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#16
Ah, right, DI sprays after the intake value has closed and during the compression stroke - that's where you got 270º. I'm still thinking about non-DI fueling cycles.

Re. the HPFP drive on the cam, I believe that Pumaspeed has a cam with a taller lob (lobs?) which they are claiming increases volume. There are also larger (higher pressure) HPFPs and larger injectors but when you add up the cost a full setup you're way over the cost of one of the 4-port aux. fuel rigs which, some argue, are better than just more DI, anyways.
 


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#17
Stratified 4 port aux fuel and V2 cams. Forget upgrading the injectors. No one tunes for them and at some point the fuel pump won’t be able to keep up. This only relates to those reaching for over
300 hp.
 




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