|
FUELforTHOUGHT
by Dave Koehler
10/8/04
 |
| I
am in the process of building
a 447ci bbc turbocharged engine.
The power adder of choice is
a PTE outlaw 88mm turbo good
for about 1600hp. I would like
to run alcohol for two reasons:
1.) to save weight(about 200
lbs.) and 2.) extra power. It
is my understanding that alcohol
requires about 20-30 percent
more fuel. Can I supply the extra
fuel via a mechanical fuel system
plummed into the intake track
to help cool the intake charge?
Or would you suggest using dual
fuel injectors controlled by
a DFI? I have an Accell Gen7
with a single and dual injector
harness, but room in the engine
bay is tight. Also how much compression
can I run with a Turbo/Alcohol
setup?
Thanks in advance,
Ray Garrett
|
|
 |
Ray,
1.) Trust your gut and your spark plugs. If you are not seeing any color change in the strap and the first threads then you are not burning enough of the fuel (rich or weak ignition/voltage) and the excess is just being thrown out the exhaust. Do not look at the egt numbers until your plugs start showing something. The old rule with a new unflowed system is, when in doubt, richen the main up .005 to .010 until slows down. When it does slow down or in your case, gets worse, go the other way (leaner) on the main jet until the plugs straighten up.
2.) If you mean adding fuel via a couple of nozzles upstream after the turbo,
I would think that throwing alcohol down its
throat and hoping it gets to where it needs
to be would be more than a little shaky. If
you meant individual nozzles per cylinder I
do not see why it would not be just as simple
to put in the extra electronic injectors and
be done with it. There is the also the problem
of the barrel valve, front mounted tank, fuel
pump and shutoff, etc. involved with a mechanical
system to plumb into the deal. So you would
have two different systems to try to coordinate
and tune. Does not sound logical or fun to me.
While mechanical injection would work just as well by itself, I would choose one fuel system or another. I think if it is EFI system then you should go EFI all the way with the extra injectors. You might as well have laptop control over everything.
Dave Koehler
www.koehlerinjection.com
|
Previous
Stories
|
| Fuel
for Thought
—
9/7/04
Dave Koehler answers your
nitrous & fuel-injection
related questions
|
|
|
 |
|
