changing injectors question about startup

[MWILSON1995Z]

Supposedly the injectors come with flow sheets for my actual injectors

[LeMarky Dissod]

Supposedly the injectors come with flow sheets for my actual injectors

Assuming the flow sheets actually apply to your injectors (there are several places out there that are NOT Fuel Injector Dynamics, that provide flow sheets that look like FID flow sheets, but turn out not to be), you'll have all the info you'll need to adjust not only the basic flow rate, but the low voltage / low pulsewidth behavior as well.

[MWILSON1995Z]

Im very new at this I bought CATS Tuning software the only changes Ive made are to the Fuel & Timing at WOT and I changed it when I swapped the injectors I have now ( not a big difference from stock though ) and I changed it when I changed gears but thats the extent of my tuning experience

[spfautsch]

You should really give more information about what you're tuning, mods, etc. up front. Save everybody the time and trouble of going and reading the introductions forum.

So you're running a '95 LT-1 with the 292XFI? I'm interested how this sounds and smells at idle, I run a 280XFI N/A with 42lb injectors.

Anyway, going from 24lb to 30lb injectors isn't a big change. 30lb to 60lb you're going to have all sorts of starting problems that won't be addressed by simply changing the static flow constant. The prime pulsewidth table will need some tweaks, and it has it's own multiplier that will need to be scaled based on the change so you don't end up flooding the bejeezus out of it. A couple years ago kur4o and I worked on this and as a result I built a spreadsheet that may save you a bunch of time and frustration. I'll try to find the thread and update this one with a link. But if I forget to let me know and I can probably find the spreadsheet easier.

Edit: I located the aforementioned thread and realized it wasn't focused much on the start-up (prime pulsewidth) tables. Gimme a day or so and I'll write up a readme for the spreadsheet and put a link to it all in my signature.

[MWILSON1995Z]

You should really give more information about what you're tuning, mods, etc. up front.

358 ci LT1 all forged bottom end 10.3:1
Trick Flow 185cc heads, 5 angle VJ all 7/16 hardware SS 1.6 Rockers
Springs are set at 160# @ 1.895 & 425# @ 1.295
292XFI HR13
Factory Intake with BBK 58mm TB
Dougs 1 3/4" headers off road X with original flowmaster 40
Powerdyne BD11A @ 7-8psi draw thru Maf sensor
ARP studs everywhere
Canton racing oil pan & valve covers
Still running Optispark buit everything is new and working for now!

Thank you for any help! I have EE Hack I use for data logging and Flash hack for writing, tuner CATS for making adjustments

[spfautsch]

Sig is updated. Unfortunately I think you'll need to use TunerProRT because I'm not sure tunercat has the base pulsewidth multiplier defined. Also the readme is written specifically for TunerPro. If you have any feedback feel free to PM me or post here, I don't think anyone has used this other than myself.

I didn't catch the supercharger in your introduction post - so are you running pure MAF or do you have patches for >1bar MAP (if such a patch exists)? Intercooler?

[MWILSON1995Z]

I see the following:

ECM Constants Table
Minimum Injector Pulse Width--------1.099 msec

I also have MAF sensor tables

I just ordered an integrated AFR guage with 2 oxegen sensors for data logging