Propane EFI

[Robert Harris]

SOMEONE has finally cracked a reluctant squeak out of me wallet.

Life begins anew for an ancient Ford 292 Y block.  

Question for those familiar with the GM ECU's.   A TBI uses a constant
frequency pulse and varies the pulse width to meter the fuel.   A Ford IAC
uses a constant frequency pulse and varies the pulse to meter bypass air.
Both about the same voltage and frequency.

Could you replace the injectors with Ford IAC's and meter the propane from the
vaporizer ( very low pressure gaseous flow ) and now have hacked the GM unit
to do propane.?   ( or low pressure CNG which someone is contemplating )

Output from the vaporizer is low pressure vapor that goes to a hose to the
mixer.  Thimking of running the output thru a pair of IAC's to a pair of EGR
plates ( did I mention dual 4 barrel manifold ) under a pair of throttle
bodies.  

Hook all the sensors up normal.  GM thinks its firing injectors - actually
varying propane flow.  Run for a little while, hack the tables and should be
close. 

This way I would get EGO, spark, knock, idle air ( from GM IAC ), egr etc
without spending a fortune.

Propane carbs "love" blow thru - so by simply referencing the vaporizer, I
could invert the rams horns and mount two small turbos and turbo it.

8 cylinder GM TBI MAP unit should work just fine. ( Moderate cam - MAP is
close enough without the calibration worries etc yada yada yada of a MAF under
boost )

Lastly, is the GM unit hackable enough to leave the EGO on full time ( after
warmup ) under load?   Response on a 20,000 lb vehicle is not an issue - but
running rich under propane is.

Thanks in advance
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