Got a ? about SAFC vs 660cc injectors

[cHo]

So I got my td05 kit installed and already pretty much maxed out my 450cc injectors at 14.5psi on a basic safe tune. Been talking to a friend about going either 580cc or 660s. I hear and read most people don't recommend going over 550cc on the SAFC2 even though technically the max would be 720ccs according to the math. I was told that if you can use up the injector(keep your IDCS around 90%) then I won't have to worry about aggressive timing advance. Is this true or no? I also have a AFPR I have waiting to be installed so I can always turn up the base fuel pressure. I just don't want to keep buying injectors and maxing them out and having to spend more money on new ones. However, I don't want to worry about crazy timing advance and blowing my motor. Anyone got some helpful knowledge? Thanks.
-cho

[Stealthee]

If no one else pipes up by morning I'll do some searching and get you in the right direction.

[vr4choke]

do you have a stock fuel pump? i dont think the stock one can supply enough for 660s. not sure tho

[cHo]

No I have a walbro 255 hotwired. Thinking about going with a bigger pump if I go with the 580s so I won't have to worry about losing pressure at higher boost levels.

[toddrs93]

Originally Posted by cHo

So I got my td05 kit installed and already pretty much maxed out my 450cc injectors at 14.5psi on a basic safe tune. Been talking to a friend about going either 580cc or 660s. I hear and read most people don't recommend going over 550cc on the SAFC2 even though technically the max would be 720ccs according to the math. I was told that if you can use up the injector(keep your IDCS around 90%) then I won't have to worry about aggressive timing advance. Is this true or no? I also have a AFPR I have waiting to be installed so I can always turn up the base fuel pressure. I just don't want to keep buying injectors and maxing them out and having to spend more money on new ones. However, I don't want to worry about crazy timing advance and blowing my motor. Anyone got some helpful knowledge? Thanks.
-cho

it can be done but it will definitely be your weak spot. Yes generally SAFC's are not well over 5500cc, plus with a TD05 kit and that much fuel you really need some kind of timing control. Typical target for the injectors is really 80%. If it is a 16g kit, with typical mods, I would say 500whp is your limit, but with full management so that you have timing control and more accurate fuel control you should be able to reach 600whp.

[cHo]

if I could keep the idcs in control, wouldn't timing stay on the stock map even with the bigger injectors?

[Girly VR-4]

you run an afc with anything larger than 550's, and you'll end up blowing your engine. the s-afc can not handle the fuel flow of anything bigger.

get a greddy e-manage or something of the like.