the other day I was talking to a guy that builds the motors for the copo Camaro and they run 80 psi at the injectors I only run 40 would this extra pS I do anything for low RPM cruisingand also high rpm? it's a turbocharged motor making around 20 psi

 

First thing that comes to my mind is if your current fuel pump has the ability to flow enough fuel at 80+20=100psi since it's currently only demanded to do 40+20=60psi. Generally people raise the base pressure when they have undersized injectors and they are trying to push more fuel through them, but like I said, it demands more of the pump possibly requiring a different or additional pump to keep it fueled.

 

Like posted above its a method of getting more fuel from a small injector, but has some issues.... fuel pumps as stated, plus some injectors just fail to operate at high fuel pressures. Tuning is the other issue.. it would need to be retuned at the higher fuel pressure. What are you hoping to gain with the increased fuel pressure?

 

i want to see if i can get a better lower rpm afr ratio. presently it around 13.5. by increasing fuel pressure you get a better fuel atomization. i run a magna fuel pro tuner part no. 4301

 

Its tough to comment on your setup without knowing the whole setup, but when you up the fuel pressure, you may get better atomization, but it adds another issue to the mix... idle injector duty cycle drops, and may counter anything you gain. Most don't get excited about idle afr as long as its not extremely rich, and just run it where it idles the best.

 

so idle will get better but at a higher duty cycle the injector will be knocked down (for example 85% dc @40 psi would be 75% dc @75 psi)? almost sound like a wash.

 

to let you know my set up is 410ci windsor 95 mm turbo on e85 gas 160 lb ev1 injectors ford white tops solid roller .650 lift 270 duration @ .050 lift 114 lsa megasquirt 1 batch fire msd programmable 7 (part no. 7531)

 

to let you know my set up is 410ci windsor 9.5 to 1 comp ratio 95 mm turbo on e85 gas 160 lb ev1 injectors ford white tops solid roller .650 lift 270 duration @ .050 lift 114 lsa megasquirt 1 batch fire msd programmable 7 (part no. 7531)

 

With more pressure the injectors will deliver more fuel per ms of open time so the injectors will be open a shorter amount of time, and with 160 lb injectors open time may already be an issue at idle. With that setup I personally wouldn't worry about 13.5 afr's.

 

ok thanks for the advise.

 

The new COPO's dont have the new LT1 engine do they?
That engine is direct injection which will be a totally different fuel system.

 

Didn't think of that, but the DI engines are several hundred psi as they are injecting at tdc of the compression stroke..

 

I thought they were 80-100 up to the injector then intensified up to something like 2000. I could be wrong though.

 

You're probably right, I'll admit I don't know much about the system, and that makes sense...

 

all the of the copo Camaros use LS motors and they are not direct injected. 3 of them are naturally aspirated one is superchargedand the Corvette uses the ls9 supercharged motor.

 

In 2012 the COPO ran at 95% duty so the extra pressure is for the under sized injectors. We put a FAST XFI on Dave Connolly's COPO and first pass it was out of injector. That was because the OEM had too small of injectors in the engine. The OEM pressure setting was 90psi to make it work.

 

yes. this guy (john lombarti) that works at the oxford, MI plant said the injector under size but more pressure so the fuel is atomized better. make sense.