----- Original Message -----
Sent: Saturday, November 17, =
2001 9:13
AM
Subject: Re: How much power can =
a stock
FI make?
Chris Stann =
wrote
I am considering building a 2.1 long block =
with some
minor performance
enhancements such as ratio rockers, lightweight =
valve
train and
ceramic-coated heads and pistons, aircraft-grade head =
bolts and
some other
anti-leakage measures. I would install this 2.1 in =
place
of my 1.9 since I
am just over 150K on an untouched =
motor.
The question: How much can my stock 1.9 fuel =
injection
handle? What
improvements can I make before I need to =
replace/upgrade
my FI system? Am I
looking at larger injectors and or just a =
fuel
pressure regulator?
Chris
I have just completed a 2.1 =
big valve
conversion into my 1985 camper.The extra power has =
allowed me to
power up the hills of Vermont and New Hampshire
at 70 mph with no problem. I had five =
people the
dog and a 25 pound turkey with the fixings in the van at the time.
There was enough power left to increase my speed to 75 mph
and beyond.
The Digijet fuel injection system is not =
what is
limiting the available power. What does limit the power is =
the
ability of the engine to breathe and that darn rev limiter that's =
built into
the ECU. As a gear head I have spent allot of time pondering this =
truth.
The question then is how do you make the engine breathe without =
loosing
longevity and drivability. Using aftermarket camshafts with huge =
amounts
of duration and lots of lift. is an example of how to loose low =
end power
and over all drivability
My method of increasing =
power threw
out the power band was to add 3 MM larger valves, blending the valve =
seats
with a Serti style cutter and minor porting work. when I say minor I =
mean the
intake port where it meets the intake seat was made only .050 ths =
larger
to match the new intake valve seat. With the aid of a flow =
bench I
was able to increase the air flow by 20% throughout the travel of
the valve. (ratio rockers don't even come close to this) I have =
posted
the flow charts on my web page see the stage three engine =
and look
for the link. The other internal changes are a minor regrind of =
the OEM
cam, more spring pressure and increased clearance in the
cylinder to allow the piston to grow.
The rest of my vans cooling system and =
fuel
injection is bone stock. I would not consider changing the heads studs =
from
stock, ceramic-coated heads and pistons or counterweighing the crank. =
Mr.
Lilley has never proven there value to me.
I invite you to drive my van and see for =
yourself the
increase in power.
Bob Donalds
Gear Head Deluxe
as always all right reserved