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Old 08-08-2012, 05:26 PM   #20 (permalink)
Smooth Operator
Join Date: Feb 2011
Location: dover tn
Posts: 147

Old Yellar - '79 MGB Tourer Drop-Hood Coupé
Sports Cars
90 day: 25.83 mpg (US)

Old Brown Ford - '91 Ford Bronco Custom

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i just ran some measurements today on my ram induction

i wonder if you have a turbo charger .. that would make a difference

anyway.. i have a NA 110CID old school gasser with a ram air down on the deck
2 in pipe feeding to an air box in front of a Skinners Union Carb

my ambient temps were about 100F on the intake

my test points were out side the pipe at the funnel and inside the pipe
with and with out a pre filter..

on the test point outside the pipe i saw
1 inch water at 40MPH
2 inH20 at 50
2.5 inh20 at 55
3 inh20 at 60
3.5 inh20 at 65

then i moved the sampling point inside the pipe

i saw i inch H20@40
1.5 in H20 @ 55
2 inh2o at 60..

then i put the prefilter on
1 INH2O @40
1.5 INH2o@50
2 INH20@60

as i was going along with the sample tube in the pipe i became aware that it made a BIG difference if i was in neutral throttle or trailing throttle

i mean what throttle setting i had . i became aware that as my manifold pressure went down did the over pressure in the pipe

at WOT 0 INHG manifold i was pulling vacuum in the pipe [ level not noted maybe 2-3 inh2o]

at my cruise setting of 15 INHG manifold i was showing

1.5 inH20 Over pressure in the pipe

i noticed at 55-60 mPH cruise AND 15 INhg MANIFOLD I WAS SHOWING 1.5 INh20 oVER PRESSURE
ON A HILL CLIMB 5% grade 40 mph top gear 10 inhg showing 1/2 in H2O over pressure

finding that throttle setting and the resultant manifold pressure transfers directly in to the induction pipe near the inlet makes my test series much more complex..
i need a data logger .. in my vintage vehicle a data logger is a rider with a stubby pencil
of some interest ..when the sampling pipe was Outside the pipe , i noticed i could detect overpressure increase Bow waves off of oncoming traffic and over pressure reduction when i entered the draft following a vehicle

this test sequence is much more complex than i had counted on

.... next i intend to move sampling point to the air box ahead of the filter
try to record ..
speed . manifold pressure and measured pressures
then after the filter in the air box

INTUITIVELY .. i perceive this manometer very useful ..
as long as i can read an induction pressure Positive , i think i am in the increase FE zone

what do you think
who can plan a proper test sequence for me ?

my final config will be with a sensor pipe after the filter in the air box and a nice little u-tube manometer on the panel [yet to be fabricated]

i expect to see the same kind of values before the filter . hard to know what i will sample after the filter..

comments ..remarks .. suggestions?
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