minytrker

iTrader: (13)

If you changed from 26 to 28 lbs injectors would the car run? Would this make the car run lean at cruise and really rich at wot? I started tuning a car today that was doing this and then found out it may have 28lb instead of the stock 26lbs. The duty cycle was hitting 128% at wot @6800 rpms.

horist

yes it will run... but the fuel trims will be in use to get it to run properly and WOT fueling will be off....

28lb instead of 26lb will cause a rich condition ... so if it's 128% duty cycle at 6800 RPM, it needs bigger injectors

why do you think it may have 28lbs instead of 26? and what is the IFR table set at (a car with 26lb injectors set to a 28lb IFR table willl run lean... )

SSpdDmon

iTrader: (10)

Ummm....2002 LS1 F-bodies did come with 28lbers, which is what you should have unless you've got another motor in it.

redsscamaroboy

iTrader: (7)

I don't think he is working on the car in his sig.
Good question about injectors though.

V8pwrdz28

iTrader: (5)

so 98 f-bodies had 28lbers, then they went to 26, then back to 28 in 02?

joecar

My 01 came with 28lb'ers.

minytrker

iTrader: (13)

Im working a 99z28 with instake and fuel rails off a 02 SS. It also has bolt ons, heads, and a cam.

MrDude_1

iTrader: (4)

yea, it will run a little rich at idle, but for the most part, the trims even it out.... i wont say who, but someone you know locally went for awhile with 28s and the PCM set for 26s..... no real probs other then the trims being farther out.

minytrker

iTrader: (13)

It is running real lean at idle and real rich at wot. I have the correct injectors tables now so I will see what that does.

txhorns281

iTrader: (12)

yes...... 01 and 02

SUTTERERMAN85

iTrader: (42)

not to hijack but the injectors are not supposed to run over 80% right. if you are over that then its time to upgrade? im at 106% at 6k not sure what its at 6.5k but i think its time for larger ones.

horist

^^^yes, 80% duty cycle is the max you should go for... they can run higher (can even provide fuel as in your case at > 100% duty cycle) but it can be risky

at 106% duty cycle w/a 99 (26lb/hr injectors) I would look into some SVO30s (or bigger if you plan on doing alot more mods)

SUTTERERMAN85

iTrader: (42)

ok well thanks i am going to be doing heads this summer. no N2O and no FI so should i go for SVO30s or the 42s? the 30's are like 36 at 3 bar right like the LS1's run corredt and 42's are what? again sorry for hijacking this. thanks for the help.
nick

horist

30s are like 36 on an LS1, 42s are about 49s on LS1s (at 58psi)

The exact calculation is in the stickies (SVO injectors are rated at 40psi so not really 3bar)

SUTTERERMAN85

iTrader: (42)

ok well thanks