Opening time: the overlooked constant

woh · Post by **woh** » Fri Mar 31, 2006 6:55 pm

SÃ©b said:

Have any of you ever used opening times as low as 0.6 ms??

Side feed Injectors, 500cc/min, 14.5psi, Bosch, intended for
TBI.
I checked the injectors on a scope at 0.5ms opening time.

sebch · Post by **sebch** » Sun Apr 02, 2006 1:45 am

racingmini_mtl: interesting point. I've seen a few posts thqt mention your point already but didn't think of it. It might well be that you're right. If for whatever reason my injectors squirt a bit while closing, my open time gets more coherent. Having said that, it looks that for port injection, the opening time tends to be AROUND 1.0 ms and I don't have exotic injectors, so I'm still puzzled. Anyway, as I said, the car responds fine and runs great, so I won't complain;

woh: as i said above, I thnik your values make sense for a TBI injector given the low pressure you)r running. Not sure port injection and 3 bar pressure are in the same category; though;

Inch'Allah!! Seb

Jedrik · Post by **Jedrik** » Sun Apr 02, 2006 7:43 pm

You may find this usefull:
http://www.msefi.com/viewtopic.php?p=10 ... ht=#101536

Jon wrote:

Mine worked out at 0.97ms.

My MSII has the injector open time in .1ms increments so there is no way to get it perfect. For me .8ms is a little to much and .7 is definately too little.

But the subject is not something to obsess about. In the end you tune VE relative to all the constants and it seems to work out.