I was wondering can i use all of the same size injectors for my primary and secondary or does my secondary has to be bigger than my primary. Cause i was thinking about running either all 4 1000cc or 1200cc for my set up....

 

depends on the computer controlling the injectors.

if its stock.... no.

 

You can use whatever size you want, assuming you have the ability to control the injectors.

 

The stock ECU will not run anything properly other than the stock sized injectors (4x458cc@2.5bar for NA, 4x550cc@2.5bar for TII). If you use different injectors, then your sizing options depend on which aftermarket ECU you use to control them.

 

Im running with a power fc, will that work?

 

The power FC will most likely have it's limits, but I've never used one, so someone else will have to answer that.

However, with injectors that size, you'll also need to run a larger fuel pump (walbro, cosmo, etc).

Why exactly do you want to run such large injectors? I ask because usually with injectors that large you already have some serious power mods (usually requiring a standalone anyway).

 

the reason why i want to run bigger injectors is because i max out my injectors which they are (primary 720cc and secondary 890cc). and yes i am running on a bigger fuel pump (255). i also max out my bnr stage 3 turbo too so thats why im up grading everything... I wasnt happy on the power that my rx7 made and maxing out everything already... (341whp with 280tq)

 

yes, you can run that combo with your power fc. the problem with big primary injectors is the idle will suffer as you cant run them low enough, and if you can, they wont spray properly.

unless you get some injector dynamics injectors.

 

your best bet would be to keep the 720's for the primary and upgrade to some 1600's for secondary, that should support about 570hp and still let you have a good cruise and idle. I am using 890's for the primaries and the idle is just rich not much I can do about it. I considered changing to 720/1600 combo but don't feel like making all new maps. or change everything to 720/2000ID injectors and get you about 700hp but thats almost double what your making now.and you will more than likely need twin 255's or something much bigger. i had to use twin 255's on my setup with parallel fuel rails to keep from having pressure drop.

 

i would suggest an 800/1600 combo as the transition will be smoother along with a full parallel fuel system.