Electromagneticly clutched supercharger with natural aspiration bypass.

[Julia Wakeling]

Hi there everyone.

I'm Tim Wakeling from Unleaded Racing Technologies, and this is officially
my first experience building a "DIY-EFI" system of any kind.  For the past 7
months, I've been testing a 1993 Honda Del Sol with a single overhead cam
(1.5 L) non-VTEC.  The goal is to achieve 50 mpg highway, 12.99 1/4 mile
times, 1.0 G's on a lateral skid pad, in a daily driven LEV (low emission
vehicle) del Sol.

To do this, I decided to fabricate an electromagneticly clutched, roots
style supercharger, intercooled, with a natural aspiration bypass actuator
motor.  The idea is to switch over from N/A, to boost with the single flip
of a switch.  By making the activation manual ONLY, you could still drive
the car to full potential without activating the supercharger, and activate
the supercharger at partial to no throttle whenever you choose to
"discourage" potential competition while stopped at a light.  Whether for
effect, (sounds like a vacuum of steroids) or for performance gains, the
system till now has worked exceptionally well.  Basically, power ONLY when
it's chosen.  The fuel system has actually done quite well for itself.
Running an adjustable fuel pressure regulator, the OEM fuel computer has
been able to calibrate fuel mix on it's own, and still stay rich enough to
not cause much of a problem at all.  I was amazed.  At 7psi, she's been
doing everything on her own.  The MAP sensor is capable of reading positive
psi, but the control module won't recognize it as a legitimate value.  As
soon as positive pressure is discovered, she tosses a check engine light,
goes into open loop mode, and the mix is perfect (according to the digital
lean/rich gauge).  Once I found this, I decided to hold off on fuel system
upgrades until I found out whether the system was going to be reliable
enough for daily use, and be able to keep itself attached to the front of
the block.  So far it has.  The car gets a whopping 53 miles per gallon
AVERAGE (mainly through lightening and rolling resistance), both city and
highway, and runs a stout 15.30 1/4 mile (17.65 on N/A).  Not bad for a
stock 105 horse engine with no work at all to the fuel system, and 147,000
miles without even a simple rebuild.  On to step 2.

Now comes the hard part.  12.99.  And holding it together.

I've decided to go ahead and swap over to a Japanese spec 1.8 L DOHC VTEC
Integra GSR powerplant.  Starting at 185 horse, it will be far easier on
driveline parts to get the performance I'm looking for.  Less broken pieces,
better streetablitiy, and a platform that has a lot more in the way of
aftermarket upper and lower end pieces available.  But, how am I still going
to get 50 miles a gallon with an engine that gets 35 mpg on it's best day?
And even better.  Where do I start on fuel maps?

This is what I think the system is basically going to require:
1 map for N/A without VTEC
1 map for boost without VTEC
1 map for N/A with VTEC
1 map for boost with VTEC

Where do I start?  I'm a diagnostic technician, with little to no experience
in designing fuel injection systems.  Yes, I can build one HELL of a short
block, but when it comes to making a system that currently doesn't exist, it
kind of makes a diagnostic technician a little bit unqualified.  I've spent
3 years at  a Mercedes-Benz dealer diagnosing and repairing electrical and
fuel systems, and the last 7 months at a new Honda store doing the same.  If
it's broken, I can fix it.  But I've never tried to "make it" on my own.
I'm doing the little project for really nothing more than personal
satisfaction.  I want to see if I can in fact do this myself.  But having no
experience in this field, other than repair and diagnosis, I've got homework
to do.

What is everyone's suggestion on my next step?  What do I need to read?
What do I need to brush up on?  How much of the diagnostic knowledge that I
have is actually going to help me, and how much is it going to hurt me?

Anything that this forum can assist me in is one step closer to where I'd
like to get.  Don't be afraid to talk over my level.  If I don't know what
you're saying, I'll know what I need to learn.  I'm looking for direction,
and figured where better to start than the do it yourself electronic fuel
injection forum?

Thanks for your time!

Tim Wakeling
Unleaded Racing Technologies

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