LPG + low octane pump gas

[Darrell Norquay]

George:

> Has any one heard of using low octane pump gas plus LPG or CNG as a possible
> octane booster? 

Yeah, I actually tried this once.  I hooked up a standard pressure regulator
to a propane tank, (vapor outlet), and plumbed the output of the regulator
into the air cleaner.  I drilled and tapped a hole into the regulator housing
on the back side of the regulator diaphragm, stuck in a fitting, and plumbed 
a hose into manifold vacuum.  The idea was to set the regulator so it was at
zero pressure at idle, and as manifold vacuum dropped when the throttle was 
opened, it would allow the regulator to open up and inject propane into the 
carb.  Sort of a vacuum enrichment valve (similar in principle to an EFI fuel 
pressure reg)...

Results were inconclusive.  The problem I was trying to overcome was pinging
in the engine no matter how much I cranked back the timing.  Turns out it
was a completely different problem (it was the transmission - be damned if
it didn't sound and act EXACTLY like detonation!  The fourth mechanic I took 
it to finally figured it out) so I abandoned the idea.  Later, I converted 
the engine to LPG fuel anyway, so it got shelved permanently.

This is a simple thing to try, anyone who has detonation problems should
look into it...

regards
dn

--

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 Darrell A. Norquay              Internet: dn at dlogtech.cuc.ab.ca     
 Datalog Technology Inc.         Voice: (403) 243-2220
 Calgary, Alberta, Canada        Fax:   (403) 243-2872            
 
       "Absolutum Obsoletum" - If it works, it's obsolete    
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