carb vs. efi

[James Boughton]

I can't help but reply to this.  There is no way a carb is going
to get close!  Just to dispute the fact on his own grounds (I
am not a drag racer) I recently read about a Pro Stock Firebird
that decided to go EFI and was breaking records.  As I mentioned
I am not a drag racer, so I don't remember the guys name, but
it was in one of those hot rod mags.  The F1, IRL, CART, F3, F3000,
and every other series where you actually have to drive the car uses
fuel injection.  I imagine that a carburetor will work at WOT at one
rpm very well, but due to the intrinsic nature of the fuel/air vs. demand
ratio (air flow vs. max. airflow) curve of a carburetor you will not get
it right everywhere.  I have no data on atomization of the fuel, but 
anyone who doesn't believe fuel control is important in a performance
application is missing out on horsepower.  The other advantage of fuel
injection is that while all the carburetor guys are trying to get all of 
their cylinders to run the same fuel/air the EFI guys are figuring out
better ways to make more power.
	I could dispute this all day long, so if the above items are not
enough to be convincing let me know and I'll tell you more.

Jim Boughton
boughton at bignet.net
engineer (with race engine development experience)
like it really matters!

----------
From: 	Tom Cloud[SMTP:cloud at peaches.ph.utexas.edu]
Sent: 	Friday, September 12, 1997 2:33 PM
To: 	EEC-EFI List; diy_efi at coulomb.eng.ohio-state.edu
Subject: 	carb vs. efi

he'p me out here .... have a friend that's a died-in-the-wool
Holley carb fan and thinks I've made a big mistake going to efi
(I'm not racing)

He's an engineer, has worked as a mechanic, owned a speed shop
and raced for a number of years, so I regard his opinion.

He argues that no top racer (NHRA is his game) runs efi.  I admit
that's probably right, but the reason isn't because it's not better,
but rather that it's too danged difficult to change at the
track ....

what do the Formula 1 guys (and others) do ??

Like I say, he'p me here .... 

 - he says he feels the carb gives better atomization -- and I
can see that a constant fuel flow rather than pulsations might
(though the pulsations are at high pressure)

 - the efi gives better fuel control, I'd think, though that may
not be important for racing

 - clearly port injection gives better fuel distribution -- but,
at 8 to 12 k does it matter ??

  ???? anyone ??

Tom Cloud

    Just because you're paranoid doesn't mean they're NOT out to get you !!