For a GT67 sts turbo setup, what would be an efficient size injector 42lb or 60lb? I'm probably goin to run anywhere from 8-12pds. Mods in my sig.

 

get the 60# better safe than running out with 42#

 

everybody going to tell you 60's. and why not they can be tuned to run great and you wont have to buy injectors twice. at 12# of boost i think 60's sound perfect.

 

I've also heard stories of running 60's and then the car runnin rich as hell at idle. I'm sure with running 60's that there has to be some type of fitment issues as well???

 

no fitament issues at all.

check the classifieds or buy from a vendor.

get a tuner

 

yes rich at idle. no fitment issues at all tho.

what about rceng.com's injectors? you can get them flowmatched too

you can grab you some :
http://www.rceng.com/Peak-Hold-Injec...550-P17C5.aspx
50#ers so you won't idle rich

NOW one thing i do not know is whether we need peak and hold injectors or saturated injectors... that you could probably also ask RCENG

Based on my calculations and worst case, at 700HP (BHP) on RCENG website you would need 60lb/hr injectors MAX to achieve 80% duty cycle

somewhere between 52# and 56#/hr injectors is what you need RATED at 43.5psi

an injector rated at 58psi (or 60psi) yielding a 60lb/hr rating would do you fine