Downside of using injector too big?
#1
Downside of using injector too big?
Ive got a bolt on car with heads/G5x4 cam, in a forged 346. How big of an injector should I use? I am getting the racetronix full pump kit, and thinking about using the SVO 42 injectors. After doing some reading on them, I saw that the 42 is what it would flow on a Ford, so on a GM it would be a larger injector, such as a 46 or so. Is this too big of an injector for me? I will be spraying a 200 wet shot, but read that because its wet it shouldn't matter what injector I am using. What are the downsides of using a injector too large? Harder to tune, bad idle, bad fuel economy? I can get the SV0 42's for $320 I believe. And these can give me some room for later when I upgrade teo a different setup. Any opinions? thanks
#5
TECH Senior Member
iTrader: (33)
i would go with the fords because the cutoff limit is lower. as long as your car doesnt see a low pulse width lower than the limit u should be fine, i have never heard complaints about the ford's. i was just about to post up my results from tuning so far,
i have an f13 cam, arf heads, all the bolt ons and 38# racetronix injectors and im runing a 12.1 ms pulse width at about 5500 rpms WOT, i still have another 1100 rpms to go, but that puts me right at 60% duty cycle at that rpm, running slightly lean, you just wanna make sure you have enough injector for your power.
ideally you want to stay larger, now i have about 20% area to play with if i want to go with a 90mm intake and whatever else, i planned it to have 80% duty cycle and about 550 fly wheel hp, i dont have close to that yet but if i do in the future ill have the fueling to do it.
i have an f13 cam, arf heads, all the bolt ons and 38# racetronix injectors and im runing a 12.1 ms pulse width at about 5500 rpms WOT, i still have another 1100 rpms to go, but that puts me right at 60% duty cycle at that rpm, running slightly lean, you just wanna make sure you have enough injector for your power.
ideally you want to stay larger, now i have about 20% area to play with if i want to go with a 90mm intake and whatever else, i planned it to have 80% duty cycle and about 550 fly wheel hp, i dont have close to that yet but if i do in the future ill have the fueling to do it.