Guys,

1. At what percent duty cycle do the stock injectors run?

2. Are the stocks 310cc?

3. What is the optimum percent duty cycle for aftermarket 440cc injectors??

Thanks to anyone who can answer these,

Jonny

 

I'll answer what I know.

Stock injectors are smaller than 310
From what I have read you should try to keep the duty cycle of any injector below 80%

 

1. 80% max to prevent burning out the injectors
2. 275cc
3. same as #1. i could be unsure if they are race injectors

 

Morris and Turbo,

OK, here is the deal. I am dropping back down to the 2.87 pulley. I spoke with RMM and they said I would be fine using the 440cc injectors with it. They said I would need fuel management but it would be ok to stick with the 440cc's. I just wanted to verify if the math worked out.

I am going to pull my Walbro 255lph as I think it is providing the injectors with too much fuel - thus why I am pulling 50% fuel and still being rich

If that doesn't help then I guess I will try and get smaller injectors.

What do you think>?

Jonny

 

that'd probably a good start. some rmm owners started with the 370's and ran out of fuel up top. i'm not sure how would your car idle with 440's though.

 

Is this something the SAFC2 can help with??

jonny

 

well, the safc can make max adjustments of 50%. didn't morris run 440's? i think tturbopimp and dr.g ran/or are running 440's. i'm just curious about the car's idle.

 

I think right now with my 440's I have 23% pulled at idle and I am an even 15.0.

Jonny

 

how's your idle? when you're not boosting, are you running rich? maybe you could compare your settings with other owners to see where you're at.

 

For comparisson sake.

I am at 370's right now but will be going to 440's to handle the 17-18psi at the end of the month

The 370s are +50 % for much of the fuel curve while under boost and at 17psi But it is still not enough and I have the fuel preessure cranked up.

Dr G is running 310's but looking to move to 370's

 

So do you think the 440's are going to be way too much at 8psi?

Jonny

 

Yes I would say absolutely positively.

I ran 310's at 8psi if I recall. DR G is gonna use 370's, but from my little bit of experience 440's are gonna be mre than you need.

 

So do you think they will be detrimental? I am having a hard job getting 310's in swap for my 440's and I don't have $500 lying around for different injectors.

Jonny

 

My guess is that it will be okay, the question is really around will it idle. There are people idling fine with 440's so my guess is that you will just wind up dialing out a bunch of fuel. But this really is just my educated guess.

370's were good for me up to about 15psi with the fpr, without the fpr it was only good for 12 psi or so.

Keep in mind your mmv since I have a different engine config.

 

MMV??

Jonny