Jump to content

Photo

Fuel injector sizes


12 replies to this topic

#1
RS777

RS777

    Elite Club Member

  • Valued Member
  • PipPipPipPip
  • 1,217 posts
  • LocationHampshire

I am interested in learning more about injector sizes and yes I could just speak to a tuner but I like to understand these critical things as well.

 

For a hybrid RS3 it is pretty standard to use 980cc injectors.

 

Someone pointed me to this simple calculator:

https://deatschwerks...ctor-calculator

 

Having done a calculation with a target crank hp of 750 on petrol it states 899 cc per min on 85% duty cycle, which sounds pretty close.

 

Now if I wanted a target crank hp of 825 on E85 it states 1286 899 cc per min on 85% duty cycle,

 

I am probably going to ask the obvious here, but am I correct in assuming I could fit 1300 cc injectors to run either E85 or pump fuel?

 

If this is correct would it run badly when on pump fuel with the bigger injectors due to their duty cycle being much lower?

 

Currently I am running Sharps Motorsports 980cc and I have been considering moving over to Injector Dynamics injectors due to the very positive reviews and options. They do both 1050 an 1300 sizes for the RS3 Daza engines.

 

http://injectordynam...ors/id1050-xds/

 

http://injectordynam...ors/id1300-xds/

 

I thought it would be good to discuss as I am always up for looking into what new technology is out there being used.

 

 



#2
flybynite

flybynite

    Member

  • Valued Member
  • PipPip
  • 110 posts

I think this will be difficult to answer without seeing logs of the engine as it is and a lot will depend on what the tuner can do with Syvecs at the bottom end of the duty cycle for that injector.

 

Low duty cycle on big injectors is a well known issue and is a problem I would make sure there is an answer for before specc'ing them. A lot will depend on what you are prepared to accept in normal running also and whether the top-end is more important.

 

Not a new problem as I'm sure you know, going big is easy, getting it to idle and run well at the bottom end has always been the trick even from back in the days of porting heads, jetting carbs and big cams.  :)



#3
Sequence

Sequence

    Member

  • Valued Member
  • PipPip
  • 56 posts

Iroz run the ID1300's in the ims850 kit and up so certainly doable along with the syvecs. Not sure if you are really gonna gain much by going this route on your turbo aside from more cost. 



#4
RS777

RS777

    Elite Club Member

  • Valued Member
  • PipPipPipPip
  • 1,217 posts
  • LocationHampshire

Iroz run the ID1300's in the ims850 kit and up so certainly doable along with the syvecs. Not sure if you are really gonna gain much by going this route on your turbo aside from more cost. 

 

According to the calculator I can't run E85 on 980cc injectors. 



#5
Buchrs3

Buchrs3

    Valued Club Member

  • Valued Member
  • PipPipPip
  • 432 posts

According to the calculator I can't run E85 on 980cc injectors.


I run e85 on 980cc injectors...so do alot of others...im at 930hp

#6
RS777

RS777

    Elite Club Member

  • Valued Member
  • PipPipPipPip
  • 1,217 posts
  • LocationHampshire

I run e85 on 980cc injectors...so do alot of others...im at 930hp

 

Thanks for the reply. I had no idea what to take into account for the direct port injectors because there is no info I can find.

 

Have you got everything finished as you would like it now?



#7
Buchrs3

Buchrs3

    Valued Club Member

  • Valued Member
  • PipPipPip
  • 432 posts

Thanks for the reply. I had no idea what to take into account for the direct port injectors because there is no info I can find.

Have you got everything finished as you would like it now?


No probs...

Finished running the ims850 kit and achieved a 9.5 at pod with seats removed...2.2 bar.. 4.09 100to200

Just installed the 9569s and another secret install yet to be revealed in a month or so.....going for an 8 second run on a car I drive daily...

#8
Sequence

Sequence

    Member

  • Valued Member
  • PipPip
  • 56 posts

No probs...

Finished running the ims850 kit and achieved a 9.5 at pod with seats removed...2.2 bar.. 4.09 100to200

Just installed the 9569s and another secret install yet to be revealed in a month or so.....going for an 8 second run on a car I drive daily...

You Sir are nuts, Haha 



#9
Buchrs3

Buchrs3

    Valued Club Member

  • Valued Member
  • PipPipPip
  • 432 posts

You Sir are nuts, Haha


Haha 😄

#10
Rooferman

Rooferman

    Member

  • Valued Member
  • PipPip
  • 75 posts

I think you're a smart man if you run ID1300s, they will give you room for more fuel if needed and they are simply a better quality injector than the generic 980cc bosch ones everyone supplies. I modified my standard wiring loom with the ID plugs so there is no adaptor harness and less to go wrong.


Edited by Rooferman, 05 January 2022 - 03:51 PM.


#11
RS777

RS777

    Elite Club Member

  • Valued Member
  • PipPipPipPip
  • 1,217 posts
  • LocationHampshire

I think you're a smart man if you run ID1300s, they will give you room for more fuel if needed and they are simply a better quality injector than the generic 980cc bosch ones everyone supplies. I modified my standard wiring loom with the ID plugs so there is no adaptor harness and less to go wrong.

What turbo and injectors are you currently running?



#12
Rooferman

Rooferman

    Member

  • Valued Member
  • PipPip
  • 75 posts

What turbo and injectors are you currently running?

 

I previously had an srm gtx35 hybrid and fuel injectors developments 850cc injectors



#13
RS777

RS777

    Elite Club Member

  • Valued Member
  • PipPipPipPip
  • 1,217 posts
  • LocationHampshire
I’ve ended up going for the ID1050X injectors which flow 1062cc. I have found out they are good for 1000hp on a DAZA engine without going over a sensible duty cycle. I won’t ever go over that so job done.



Reply to this topic



  


Audi RS3OC Forum is Powered by APR Motorsports UK
© 2013-2014 Audi RS3 Owners Club | All rights reserved | This club and forum is not officially associated with AUDI AG.