injector size

[mjboehm]

i am getting ready to buy a set of injectors for my 90 tsi awd.
the mods i have done are:
2.3 liter
16g
walbro 255
avc-r
data logger
act 2600 clutch & flywheel
i am getting ready to buy 2nd gen maf,sacf,fmic,stage 3 keydrive chip.
planning on buying a bigger turbo after that 20g or same size turbo
so i really didn't know what size injectors i need. any info would be great.

 

[dsm-onster]

I've seen Kediver chips / dsmlink / DSMap (all which use the factory ecu proccesor) do fine w/ 1000cc injectors. Why not get the biggest? since they're all about the same price.

 

[Travi2506]

Agreed. DSMlink and 1000cc's... Idle like stock and always have the option for more fuel...

 

[mjboehm]

thanks for the help

 

[Travi2506]

Don't wanna hijack your thread, so I sent you a PM about your setup...

 

[burnnxs]

bigger is good but it depends on your goal too do you see a shep tranny in your future i mean 400+whp ? get the picture

 

[dsm-onster]

What's the difference between 550cc injectors and 1000cc injectors?

 

[Travi2506]

The 1000cc's flow almost double that of a 550cc... I see you have a walbro 255... Do you have a regulator?

 

[dsm-onster]

The 1000cc's flow almost double that of a 550cc.

I know that!

I'm asking why would one suggest a small injector over a large injector considering the fuel control choice discussed.

 

[mjboehm]

no not yet looking into buying fpr too

 

[Eastwood95]

It doesn't look like you need anything bigger than 660cc injectors...........I would get the AFPR first

 

[Splitpi]

I know that!

I'm asking why would one suggest a small injector over a large injector considering the fuel control choice discussed.

Dead Time is the issue with injector driveability... let me clarify... streetability, not the amount of flow. It just happens that the larger the injector the more the amount of dead time tends to very.

With that said, you should be able to tune the 1000cc with DSMLink and have the car behave reasonably well.

 

[dsm-onster]

Try perfectly well. Like mine, and countless others. Also A keydiver chip does the exact same thing. The deadtime the ecu uses to calculate the injector pulse is rescaled or rescalable. It will idle like stock. Something like 1600 cc injectors may not like to idle like stock. But, because they are so large. you run into spray pattern and atomizing issues.

I'm not trying to be rude. I understand what you mean.

 

[steve]

Dead time is just another parameter.
What really makes the difference is how well matched the injectors are and how consistant they are at short pulse widths. If you have a set of injectors that have a poor pattern and are all over the map from one pulse to the next at short IPW's then they are going to idle like heck. They could have a huge deadtime and that can be accounted for as long as they don't drown the car in fuel at their minimum pulse width.

Steve

 

[dsm-onster]

I run FIC 1000cc injectors. I've heard of zero complaints. FIC must do a good job picking/machining their injectors