Hi all Does anyone know what the limits are in terms of power that the AP2 (return less system ? (I'm running the f20c).

I've just acquired a new kit to push to 480whp, but I think I may be in a bit of a pickle as I've seen on SOS' webpage that the factory return less system on 06' models are limited to 375whp, despite running a larger pump.

I'll be using a Walbro GST 450, DW1300's and will be running e85. Would just like to know if there are some out there that have had no problems on the Ap2 running above SOS's recommended threshold.

Sorry if this has been answered before, but I'm limited to the s2ki app this week as I won't have access to a computer Cheers fellas

 

You will run out of fuel (100% duty) around 400-450whp I ran into the same issue last year. Ended up getting the sos return kit.

 

Damn that sucks. Do you know if the SOS upgrade is limited to using their recommended fuel pumps as I'll be using the walbro 450 and e85? Cheers mate

 

You can use any fuel pump you want basically they modify a oem 05 & under fuel carrier to work with our 06+ all your doing is converting to the oem return setup. I am using a aeromotive 340. I was thinking about using a Walbro 416 but you would have to modify the carrier a bit and run a relay setup with better wiring.

 

The main problem is the banjo fittings going into the fuel rail. That is where all of your restriction happens. You can have double fuel pimps, and 2000 cc injectors, but if the fuel can't get to them, it doesn't matter. Look into the radium fuel rail with fuel line, it's a gorgeous piece and it flows a lot better.

 

Thanks guys, much appreciated