Upgrade injectors?

**Juanmiguel** · 06-22-2011

So I just made the first scan with the new setup. looks like the max IPW I've got so far is 16.8. I still have to lean the AFR for the SSIC. I'm guessing that I can still run a 3.0 pulley with the stock injectors. What do you guys think?

I do plan to get bigger ones, but not just now.

**matt5112** · 06-22-2011

IIRC 18.5 is about as high as you'd want to go.

Some say 21, but thats kinda high.

**gtpsleeper** · 06-22-2011

is that with your 3.0 on? sometimes IC guys can get away without upgrading right away because they can run leaner IIRC....

**blueguy** · 06-22-2011

Pretty sure once your hitting 20's you need bigger injectors. Those don't look like they are maxed out to me.

But...any smaller of a pulley...or if you up the fueling in your tune...I bet you'd run them dry.

**matt5112** · 06-22-2011

IDC of 85%+ is time for an upgrade.

Fuel Injector Pulsewidth Calculator
Inputs:

231.3, 850 , 6000, 10, 6, .5, 21, 300, 1, 42.5, 1, 4.

Output:

Injector Size @ 80% recommended duty cycle (lb/hr): 31.25 Lb/Hr
Max Hp with recommended injectors @ 85% duty cycle: 318.750 Peak Hp
Max Pulse Width Permitted @85% duty at peak rpm: (Ms): 17.000 Ms Peak
Max HP with Your Installed Injectors @ 85% duty: 433.500 Max Hp
Idle Millisecond Pulsewidth: Installed Injectors 1.700 Ms Idle
Projected cc's per minute: Installed Injectors, per injector at idle:3.503 cc's / Inj.

**Juanmiguel** · 06-22-2011

Originally Posted by gtpsleeper

is that with your 3.0 on? sometimes IC guys can get away without upgrading right away because they can run leaner IIRC....

That was on a 3.1, I still need to buy a 3.0 assuming that I also max out the spark advance on this one.

My guess is that I can get away with the stock injectors because of the altitude. My rationale is that with less oxygen in the air, less fuel used. I also think that if I bring it down to sea level, the injectors will be maxed out.

Thanks for the info guys.