I am considering purchasing probably a to4, and looking to make in the 350 range. I currently have 550's in the primarys and 720's in the secondarys controled by the wonderfull SAFC. My question is will the 720's support that kind of power? I was debating either putting 720's in the primarys, which I heard could cause flooding issues, or perhaps 1100 secondaries, which if I remember correctly is outside of the scope of the SAFC. I am really trying to stay away from a standalone at least for awhile, but I still want to be safe. I will probably only be running 10 PSI. Just wanted to see what those of you with experience have to say. Thanks for your time, I really appretiate it.

 

no they won't. you can try 4 720's or just add 2 1680's with your 550's. Not sure if your safc will tune down the 1680's enuff. You will also need a upgraded fuel pump.

 

Are we talking 350hp at the rear wheels?
Even 4 x 720's will not support that kinda power levels at stock spec fuel pressures.
There are several fuel injector versus power output calculators available.
You should play with the numbers to get an idea what you should be running.


-Ted

 

rx7.com has a good calculator

 

I am running a BNR stage3 (suppose to be good for 350rwhp) on a street port I am running 4x720s and the other mods listed in my sig.