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Old 08-23-2018, 12:59 AM
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mrvette mrvette is offline
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Default Batch fire DPFI and economy.....

OK my '72 has a stock cammed basic LT1 engine setup on a L98 engine with HEI up top in back the way GOD intended as we know sparks and water don't mix.....

And we know the batches are fired right bank/left bank back and forth.....

Long time ago under one of the projects I forgot to ground one of the batches....driver side....but engine seemed to run fairly decent, obviously not WELL, but believe it or not, it DROVE down the street with rather little complaints....sure it was rough....but it did get down the road......

at one point I got to thinking, I know that's dangerous.....and temporarily rewired the batches to 7218/4 corners and 4365/centers....and engine ran just fine, but too lazy to make it permanent, I just left the stock configuration alone.....

NOW I get thinking....what IF......I reverted to the corner/center wiring and then pulled one batch off line....how would engine feel?? would the crank get cranky and disagreeable?? would 7218 be the same as 4365?? as far as drivability is concerned?? would it hurt anything much to leave it that way for say a minit at freeway speeds before reverting to the other batch??

how about teaching the computer to drop every other batch fire request, alternating back and forth?? 7218, nothing 4365, nothing 7218 etc.....

what say you tech heads???
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Old 08-23-2018, 05:54 PM
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BBShark BBShark is offline
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The way I have heard is that batch fire occurs (starts) anytime in the cycle and then the other injectors fire 180 degrees later. So most of the time the injector operates with (most of) the intake valves closed. So, timing doesn't really matter.

As far as firing the injectors every other time, I think the computer would try to inject twice the amount of fuel to keep the fuel/air mix from being too lean.
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Old 08-23-2018, 07:30 PM
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Quote:
Originally Posted by BBShark View Post
The way I have heard is that batch fire occurs (starts) anytime in the cycle and then the other injectors fire 180 degrees later. So most of the time the injector operates with (most of) the intake valves closed. So, timing doesn't really matter.

As far as firing the injectors every other time, I think the computer would try to inject twice the amount of fuel to keep the fuel/air mix from being too lean.
Yeh, you correct....oh well....
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