Help tuning with larger injectors

[RonnieW]

I want to switch to e85 eventually. I need to go from 83 to 120 lb injectors. I know I should tune the injectors in on 93 oct gas first. I have a decent tune on the 83 lb injectors now. I tried changing to the 120s and was have a hard time getting it to idle. I need help with the tune to get started. I have the injector data attached and need someone to tell me which tables I should put the data in. I tried but feel like I may have inserted some wrong. After the tables, what changes should I make to the 83 lb injector tune so I can start the 120 lb injector tune? I have a vac referenced return style fuel system. Thanks


GM_-_120lb.xls

[RonnieW]

SDAutoVE_0264 world heads 120 injectors e85 first 0007.ctz
This is the tune file I started playing with. Please see where I put the wrong date in. Thanks

GM Offset=table?
GM Flow=table?
GM Spa=table?
GM min PW=table?
What else needs changing to go from 83 to 120lb injectors?

[joecar]

GM Offset=table?
B3701
Use the first table on the GM Offsets tab, you have to transpose it.

GM Flow=table?
B4001
Use the first table on the GM Flow tab, you have to transpose it

GM Spa=table?
B4005
Use the first table on the GM SPA tab, you have to transpose it

GM min PW=table?
B4003
Use the first table on the GM min PW tab, you have to transpose it

What else needs changing to go from 83 to 120lb injectors?

You have to set B9021 Minimum Transient Pulsewidth to some smaller value.

[RonnieW]

Great. I'll try these tomorrow or as soon as I can. Should the engine start up and drive with only these changes to where I can adjust the VE table to the AFR I need?

[joecar]

Did the engine run ok on the previous injectors...?

Post your previous tune (which had the previous injectors).

[joecar]

If it ran ok with the previous injectors, it should run ok with the new injectors as long as the data is correct for them.

You may have to adjust B9021 to get as small a pulsewidth as you can at idle.

[RonnieW]

If it ran ok with the previous injectors, it should run ok with the new injectors as long as the data is correct for them.

You may have to adjust B9021 to get as small a pulsewidth as you can at idle.

I don't have B9021. What else could it be?

[joecar]

I don't have B9021. What else could it be?

See attached, unzip contents, copy the *.cax file to C:\Program Files (x86)\EFILive\V7.5\Calibrations

then restart tunetool, search for B9021, make its value half.

[RonnieW]

See attached, unzip contents, copy the *.cax file to C:\Program Files (x86)\EFILive\V7.5\Calibrations

then restart tunetool, search for B9021, make its value half.

Got it, Thanks Joecar

[RonnieW]

SDAutoVE_0265 120 injectors gas 0000_0004.ctz

Got it fired up and idling but it's pig rich and doesn't seem to change any from around 10.8 afr. I have reduced the VE table by about 50% around idle without any changes in the AFR. I figured that I had better ask for help before I go any further. I also reduced the b9021 table by another 25% and no help.