Subject: Volunteer needed.
From: ACRE
Date: 12/13/2004, 8:05 PM


I have been working too hard lately what with all the variations
of 3D intake manifolds layouts I have been doing for Jerry.

I need somebody that knows how to do spread sheets to take the
two lowest dyno curves off this torque chart and convert them
to HP curves in gif or jpg format. This is the best torque
information we have on 13B geometry peripheral port engines.

The HP formula is torque times RPM divided by 5252 of course.

Paul Lamar

Here is a plot of the lower curve using the data points I
interpolated. These are the XY points I used if you want to double
check for accuracy.

I'm still working on curve +150

RPM X 1000      Torque (N-m)    ft-lb   HP
4               425             313.46  238.74
4.28            450             331.9   270.48
4.5             461.5           340.38  291.65
5               476.9           351.74  334.87
5.45            500             368.78  382.68
5.5             502.7           370.77  388.28
5.78            550             405.66  446.44
6               589.5           434.79  496.72
6.1             600             442.54  513.99
6.3             604.2           445.64  534.56
6.5             600             442.54  547.69
6.67            589.5           434.79  552.18
6.83            573.7           423.14  550.27
6.93            550             405.66  535.27

--
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (soon)

Further along to perfect Bob.

Plot another 1000 RPM and we will have it.
Tracy is running a 73 inch prop and he is getting 7300 to 7400.
With a smaller dia. prop and a 2.85:1 PSRU we could be looking at 8000
RPM with P-ports.

Paul Lamar



Bob White wrote:

Here is the +150 data.  Matt's is prettier. :)

My interpolations form your second gif file and calculated HP.

RPM X 1000      Torque (N-m)    ft-lb   HP
6.02            560             413.03  473.43
6.25            593.5           437.74  520.92
6.67            611.25          450.83  572.56
6.93            597.5           440.69  581.49
7.08            581.75          429.08  578.42
7.27            553.75          408.43  565.36

Bob White



http://www.bob-white.com
N93BD - Rotary Powered BD-4 (soon)


If you overly these two (175 and 150) I think you will be able to see the
effects of skin friction drag in the intake pipes. The 150 being shorter
and less draggy than the 175 while still giving good power at 6000 RPM.
Namely about 235 HP. I don't want to put too much credence in this
as experimental error could be a factor. Also cruise BSFC could be hurt
if the pipes are too short. We will never know until we get a dyno.
 
Paul Lamar
 
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