Audi s3 8l, the build

Because you're at the limits of the injector, what if a freak event happens like you get too hot and the ecu wants to protect the engine and throw more fuel in, it can't, they're already at their max.
Margin for error.
Way better to have an injector operating at lower duty cycles where it can comfortably go further if needed.
 
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superkarl said:
Because you're at the limits of the injector, what if a freak event happens like you get too hot and the ecu wants to protect the engine and throw more fuel in, it can't, they're already at their max.
Margin for error.
Way better to have an injector operating at lower duty cycles where it can comfortably go further if needed.
Click to expand...
so its better to use 550s then the 440s to make them work less and still have more togo? im gonna upgrade to an inline extra pump should be enough for the 4bar system
 
VAG-Slag said:
440's @ 4 bar should be fine, but they'll likely be at somewhere near 90% duty cycle at full power. And obviously the pump will be under a lot more strain at 4 bar than it will at 3... There is a mathematical equation to calculate injector duty cycle vs air flow (i.e HP), perhaps someone (Bill!?) can expand on that a bit for us?

When it comes to high duty cycles though, no one has ever really been able to explain to me why a high duty is such a bad thing... At the end of the day an injector is either open or closed, I personally don't understand why having an injector open 90% of the time is that much worse that it being open 70% of the time..
Click to expand...
ill try the 550s and a inline pump and a 4 bar regulator and take it from there x)
 
audi upgrades
3bar and 550's is enough for a hybrid... I used a 4bar and 550's on a GT3071r

<tuffty/>
 
<tuffty/> said:
3bar and 550's is enough for a hybrid... I used a 4bar and 550's on a GT3071r

<tuffty/>
Click to expand...
thanks for the advice, im gonna order adjustable-fuel-pressure-regulator, fittings, nuke-rail, the 550s injectors, fuel-pump, a bigger intake-manifold
 
<tuffty/> said:
At the time I was just over 400hp...

I run 750cc at 4bar currently on a bigger turbo

<tuffty/>
Click to expand...
sounds great, you use the original 1.8t big port? or have you bored?
 
okey, after alot thinking i changed my plans in the build,
so i ordered, southbend clutch stage 4 with SBC Lightweight Flywheel, ARP flywheel bolts, IE rifle Drilled rods,calico coated bearings, walbro inline pump, 630cc injectors,4" air filter, ARP Main Studs, Arp Main bolts, Arp everything in the engine, Brembo brakes and pads front and rear,oil Catch can, New Oil cooler system, volt gauge, oil temp gauge, oil pressure gauge, exhaust temp gauge,new 80mm tip, new race downpipe 3" with 200 sport cell, so far, waiting for my costum hybrid turbo to be done

http://s1190.photobucket.com/user/Charmz6/media/IMG_08321_zpsbafy4bbr.jpg.html

http://s1190.photobucket.com/user/Charmz6/media/IMG_08331_zpsq3ayrhar.jpg.html

http://s1190.photobucket.com/user/Charmz6/media/IMG_08341_zpsutpb3xg8.jpg.html

http://s1190.photobucket.com/user/Charmz6/media/IMG_08351_zpsivpziftm.jpg.html

http://s1190.photobucket.com/user/Charmz6/media/IMG_08431_zps0mugkvhr.jpg.html
 
IMG 08411 IMG 08421 IMG 08401 IMG 08371 IMG 08431
 
You bought Deka's? oh dear.... they have really crap linearity at low pulse widths (idle) and will turn fuelling to cr@p on ME 7

Should have struck to the Bosch

<tuffty/>
 
not using ME 7, gonna update to Autronic SM4, so iwont have any problems with a fine map
 
Charmz said:
not using ME 7, gonna update to Autronic SM4, so iwont have any problems with a fine map
Click to expand...

Still depends on if you use wideband lamda to control fuelling on idle and how well your standalone copes... on fixed duty mapping you can map around the non linearity as the ECU won't be trying to compensate by monitoring AFR on idle... ME7 can run away with huge swings in fuel trims as its constantly battling the inconsistent fuel delivery.

Good luck with it though... be interesting to see how the car copes running on standalone...

<tuffty/>
 
yea, the build will be fun to se finished :p
 
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