nuggie

doing a lot of top end upgrades this year and looking for some injectors I have found the lbs/min I want but I can't figure out what pin I need everything I am coming across has the same connection as the LS motors and I didn't look to closely at it but the injectors plug ins don't look the same. What our or injector style plugs called I know the ls areuscar/ev6 but what is ours?

nuggie

I also was doing some research and found that some ecus cannot controll injectors over a certain lb/min anyone have info on this

AmorgetRS

iTrader: (6)

Ours are commonly called EV1s same as the LS1/LS6 injectors.

The stock ECM cannot control low impedance injectors/peak hold injectors. They can control any high impedance injector.

ULTM8Z

You can upgrade to Bosch III style injectors, they run fantastically, but they'll require retuning the computer even if you get the same advertised flow rate.

nuggie

I was planning on having it retuned anyways I am switching to the HSR and some worked over heads. so what physical size injectors do I need to use the fuel rail that came with the HSR ... a little side question since the vss supplys a digital signal to the ecu can the speedo be corrected with the tune?

AmorgetRS

iTrader: (6)

The Bosch III injectors should fit perfectly with the HSR.

You cannot adjust the speedo through the '730 ECU.

nuggie

whole cow those are much cheaper then I was looking at with the other ones, I can;t seem to find a flow rate for these, are they all the same

AmorgetRS

iTrader: (6)

No, there are a bunch of different sizes for them. I think they range from 19 to 27 or so pounds, maybe as high as 42

nuggie

cool according to my calculations I can push 500 at the crank and still only run 42lbs of fuel pressure and still be at less then 80% duty cycle leaving me room to increase fuel pressure and duty cycle depending on what more tinkering I could do to it. I read somewhere about injectors being too big and killing the idle of a car how does one calculate this or is it something really worth worrying about my brother is running 60lbser on his stock 5.3 of course he is running magaquirt not the factory ecu. I found some 42lbsers for 1/3 the price I was expecting too you think these might be over kill? Honestly for the price I think it might be worth the cost for the experience.

AmorgetRS

iTrader: (6)

Injectors can only open and close so fast. Too big of an injector for your motor and you have idle issues because it's dumping too much fuel. Get the right size injectors for your motor.

Not sure why anyone would ever run 60lb injectors on a stock 5.3... I only ran 42lb injectors on my turbo'd LS1.

nuggie

:dunno: so I guess over kill isn't something I should be worried about too much lol

ULTM8Z

Don't just get the flow rate... you have to get the right battery voltage offset correction tables as well.

There are several things to do in the ECM to get it running right with Bosch III's.. and you'll want a wide band O2 installed to get it right.

Correct injector flow rate (this will be an iterative process that interacts with the VE and PE tables)

Correct Voltage Offset Correction Table vs Battery Voltage

Zero out the Low Pulse Width Correction vs Base Pulse Width (the Bosch III's don't need "help" at low pulse widths to get enough fuel out)

Get the VE and PE tables just right...

nuggie

I already have a wide band o2 sensor installed, I was also planning on paying to have a dyno tune done I hate to do that but I have seen lean tunes fry motors and I am no where near comfortable enough to do it myself, I will do some more research on what you said because I understood none of it lol but I know there are plenty of DIY tune forums on this page