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Hi all.
Have been tuning a 355 with a blower and E85 the last few days.
It has 60lb injectors and we have tuned it sweet on those until full duty cycle is used. We have since put in both 80lb and 1000cc injectors but both cause issues.
I have set the inj flow to suit (or thereabouts) and have tried single fire etc but no matter what I do I cannot get rid of a misfire at low RPM and causing the car to run on 6-7 cylinders. I'll attach the 60lb tune and the 80 lb for compare. Can the 305 drive a larger injector or have I missed something here.

Tunes attached. $12p

I have tested injector pulses and the spark from the dizzy, both are present. It appears i cannot get the minimum pulse width down enough to make it run clean?
ANY ideas would be helpful. Even a base tune for a ECU that has 80lb or 1000cc injectors that i can use please

Not on my computer at the moment but check what you have the minimum injector pulse width set at. The ecu calculates the pulse width required then checks it against the minimum allowed, if it is less than this it uses the minimum value, with large injectors this is enough to flood the engine at low speed low load conditions.

Yoda has a good point, I had the same issue with 40LB injector on my car, it bucked, backfired at part throttle and kept flooding upon start up.

Found the min pulse width to be too high for the large injectors and was effectively flooding it at low speeds/load. reduced it down to iirc 2ms and it was perfect.

It makes sense to me also. Can yo utell me where in the $12p XDF i can find it though? I cannot see it in version v112

should be these 2.

Also have a look at "Injector - Injector bias add-on vs Injector pulse width"
For low pulse widths it adds some additional time, for large injectors this may need reducing.
Really need to get a log of it happening and see what the pulse width is, if it is in this region may be worth a try, don't just go blindly changing things or you'll end up in a real mess.

Vlad I have zeroed both of those parameters out,
Yoda I have also zeroed that whole table out.

It appears no matter what I do the injector BPW won't go less than 2.5 m/s. And the car would not run on all cylinders at low RPM.
For a trial I wound the base fuel pressure down to 30psi (the regulator minimum) the car did start to run on all 8 as checked with a temp gun on the exhaust but it still has a misfire.
Any ideas why the ecu isn't commanding less than 2.5m/s? I have the ecu forced in single fire mode to try and get the BPW better but no luck.

Any logs of the big injectors running