injector sizing question....

bansheeboy420 · Post by **bansheeboy420** » Sat Aug 26, 2006 11:21 pm

I'm putting efi on my yamaha banshee (400cc - 2 cyl - 2stroke)... I have 38mm TB's off a gsxr 600 '02... They came with 240cc injectors which is just enough to run the motor like it is. (that would be about 90% duty cycle) BUT, I'm going to be putting about 30lbs of boost into it after I get it running right. My question is... If i go to 72lb injectors for the turbo app. will I have issues with idle or anything else...? Simply because they are so big. Or should I use the 240cc as mains and piggy back with another set (around 50lb) into the bottom case to cover the turbo?

Whittle!... HELP!

bansheeboy420 · Post by **bansheeboy420** » Sun Aug 27, 2006 1:46 am

ok I've been reading some other treads... If I set up 2 injector banks... using the 240cc injectors up to an 80% duty cycle, can I then setup the larger injectors to start firing when boost is appied? Can msII apply more fuel according to boost? Since I'm using a maf instead of a map, will I have to set it up according to airflow... ok my ears are starting to smoke.

Someone please tell me how I can set up 2 sets of injectors with my odd application. (2-stroke turbo)

I read in mega manual that you have to fire the secondaries all the time... be it for a very short time... but they have to fire. Is this right? if so then I'd have to set them to a very small shot until called on for volumes of fuel when needed (boost).

I'm not quite an expert but I'm trying!

bansheeboy420 · Post by **bansheeboy420** » Sun Aug 27, 2006 3:54 pm

Ok so i really can do it either way. Since ms2 has the higher resolution I won't have to worry about dribble or poor idle....I think I got it. Thanx lance your the MAN!!!