The following is an excerpt from Full Article Text.
Date: Fri, 03 Sep 1999 16:52:29 PDT
From: "Bjorn A. Lovoll"
<bjorn_lovoll@hotmail.com>
Subject: [E36M3] ERT Pulley - personal
results
I just had the ERT twin pulley (1999 style) installed on my 1999 M3 convertible.
I then had it tested for voltage output.
At idle(~500rpm) (no load) it puts out 13.96volts. At 1500 rpm (no load it
puts out 14.00, which is when the voltage regulator
kicks in and keeps it
from going higher.
I then did a full load test. EVERYTHING turned on. Emergency lights (aka hazard lights), head lights, driving lights, interior lights, HK stereo (cd changer), heater set to max, AC on, car phone wired in and on, both seat heaters, etc.. (ie: if it was possible to draw power it was on).
At idle(~500rpm) (max load) it puts out 12.55volts. At 1500 rpm (max load) it puts out 13.95
At 12.55 your car is fine. Everything is working. And when is the next time
you will have as many items as I have turned on at the same time... never. Was a
test case where I loaded the system down as much as I could. The BMW electrical
tech I had do the work (at Strictly BMW in Bellevue, WA) told me that the output
was very close to stock. And was an idle modifcation from his point of view
(they did not sell me the part, only did the install and would have made more
money if I had to pay them to take it back out). He also told me how the system
normally works. He said the under normal load the stock system puts out around
16v or higher and the VRE corrects that down to 14. And that having a system
such as that created by installing the ERT is actually better. He also said the
part was extremely
well made and several pounds lighter.
I haven't driven it much yet. Three hard launches and a short 15 mins
drive-around. But it is noticably stronger. It pulls harder and revs
faster/smoother. I'm going on a long trip this weekend (putting about 1000 miles
on the car), should be long enough to get a good sample for what it does
performance and gas mileage wise (since it will also improve mpg). Thus far,
this seems as close to a free lunch as I've seen. Reports that the BMW charging
system is closer to 12.0000 volts then other cars(as I've seen written
elsewhere) isn't very accurate. Since the BMW charging system
isn't even
voltage regulated until it hits 14.01. And the fact that normal for the system
is well over 16. Clearly it represents more of a drain then it needs to. Also
the part replaced is very old and heavy and contains sprockets and other heavy
junk from a previous engine design which is no longer needed.