Netres availability

[WEG1192 at aol.com]

In a message dated 8/20/2001 11:55:47 PM Eastern Daylight Time, 
nwester at eidnet.org writes:

> If this TBI is just spraying into the bottom of the manifold anyways--is it
>  really going to matter ?? I've seen some virtual fuel "pools" at the bottom
>  of some 2.0L TBI stuff--and it seems to still work. If both injector 
drivers
>  went to a "single injector"--would that make a big difference ??
>  
>  Lyndon

I have researched the archives for TBI applications of the 7730 ECM, and it 
appears that although it will work, it won't work well. To me, this is due to 
the batch firing of one injector driver. If fuel pooling at the bottom of the 
manifold really was an acceptable way of running the engine, I would think 
the 7730 would work ok, which it doesn't per the archives. Again, it all 
boils down to distribution of the air fuel mixture to all cylinders evenly 
for a smooth running engine, and the batch fire stuff only works on port EFI 
where the backwards flow of fuel and air from one runner to another is not 
very likely. Since TBI applications inject fuel way before the runners split 
up and go to the cylinders, the majority of the fuel squirt is going to go to 
whichever cylinder's intake opens right after the fuel squirt. Now at higher 
RPMs it may be that the fuel squirt duration lasts long enough for more than 
one cylinder to get an adequate fuel shot. So if you find that the engine 
runs better at high RPM with a batch fire ECM and TBI, this would verify my 
position. Even though the engine may not be getting an evenly distributed 
fuel air shot at lower RPMs, the power demand on the engine may not require 
that anyway. But I can't believe the engine would run with acceptable 
emissions this way.

Maybe he should try a 7730 with a 4 cylinder engine and use the $8D mask with 
the cyinder select set to 4 cylinders. This is a known hacked ECM. I think 
Chet Wagner has done this and he says it works well. JW
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