Can I use the stock injectors if I'm putting out 380+rwhp? I'm thinkin about switching the gm 846 cam (222/230) and I would like to keep the stock injectors if I could but I'm guessing I can't. If I can't, would the racetronix 28lb or 32lb be a better choice for me?

 

yea, a "general" rule i think is that the stock ones are usually good til about 400rwhp

 

I dont think an 846 cam will put you at 380+rwhp

What duty cycle are your injectors at now?

 

I'm probably at 360 RWHP+ (put out 352 with 12.0 a/f, 48mm throttle body, and my pre-load adjusted too tight on my comp R's) with the 210/224 so I think 380rwhp would be a piece of cake. I haven't had a chance to see my injector duty, does anyone have the forumla to calculate it from the injector pulse width?

 

Try to get a reading on the duty cycle, i have always been told you dont want them above 85%.

You are probably aproaching that now with your stock injectors and your current setup.

 

All my scanmaster reads is the injector pulse width in miliseconds though, how do I convert that into duty %?

 

I have to second that you won't hit 380 rwhp w/that cam. Even if you are at 360 rwhp now, you'd be doing good to pick up 10 rwhp w/the cam swap. Something like a GM847/CC306 would give you a better shot at 380 rwhp (depending on how good your heads are).

As jchevy stated, 85% duty cycle is a pretty safe number. You are probably right around there now and w/ a bigger cam/more power, you will likely be past 85%. I've seen guys run 90-95% duty cycle, but it's not a good idea.

Get the car scanned.

 

Duty Cycle % = (Pulse Width * RPM)/1200

 

Well I went ahead and ordered the racetronix 32lb injectors, I figured I shouldn't chance it with the stockers...

 

I'll say i also don't think you'll make 380. You basically are running a CC305 and i dont' think anyone has put down that kind of power with just ported stock LT1 heads. I do think you made a good decision with going with bigger injectors though.

 

I'm going to try to prove everyone wronge.