Upgrade to 36lb injectors

[cjrpony]

I had the car on the car on the dyno a few weeks ago (dyno challenge) and was running out of fuel by 5300-5500 RPM. I just looked at my last datalog on the Tweecer and my injector duty was at 88% at 5500 rpm. I am running at 39 psi fuel pressure. Should I bump it up a little or upgrade to 36 lb injectors? I am running 30lb now.

 

[revhead347]

Absolutely no reason you should need 36lb/hr injectors with that combo. Bump up the fuel pressure.

Kurt

 

[final5-0]

At OEM pressure and with your additional cubes, I can see you pushing
those 30's to the limit

I like to tune as Ford does with OEM pressure

If you don't wanna up the pressure you only have the other option which is to go with larger inj's

Seems like to me peeps have said 36's are hard to find these days

Grady

 

[cjrpony]

Thanks, one for bumping fuel pressure, one for bigger injectors. I guess I could up the pressure and see what happens. It's free and I can alway put it back. I do know where I can get my hands on a set of low mile used 36ers if I need to.

 

[bayellowstang]

I'm in pretty much the same boat. I plan to throw a turbo on it w/83lb injectors so I will be bumping my pressure until that happens.

I say if your not making more changes get the 36ers. If more power is on order bump the pressure until those mods are done and get 42's.

 

[final5-0]

Just know if you already have your CL portion of the tune all setup
and stable ... upping the pressure is gonna hose up that part of
the tune

Grady

 

[toyman]

I'm not a fan of bumping pressure to get more fuel. The injectors have a designed fuel delivery rate and are good to deliver that fuel to the 80% duty cycle at the specified pressure. When you exceed the design specs fuel delivery is no longer consistent which can result in AFR's that may not be reliable and/or consistent as well. Since larger injectors can always be tuned to actual needs it just seems foolhardy to gamble with undersized injectors by jacking up the pressure.