What's the difference in oil pressure senders: Thin vs. fat?
11-03-2010, 10:13 AM
#1
What's the difference in oil pressure senders: Thin vs. fat? I have seen two kinds of oil pressure senders... thin ones, and fat ones. I included a picture of each. These are NOT switches that run a light on the dash, but sending units that run the gauge.
What is the difference between the two? Is one better than the other? It seems like all the newer cars (last 10 years, at least) have the thinner units. Is there a reason none of the new cars come with the fat ones?
I am trying to use a thin one because I don't like the way the fat one fits with the LS1 manifold. Any information would be a big help.
What is the difference between the two? Is one better than the other? It seems like all the newer cars (last 10 years, at least) have the thinner units. Is there a reason none of the new cars come with the fat ones?
I am trying to use a thin one because I don't like the way the fat one fits with the LS1 manifold. Any information would be a big help.
11-03-2010, 01:06 PM
#2
My crazy theory: it may be that the large one uses a bourdon tube or diaphragm with a potentiometer and the other uses a MEMS device. If the output is the same, I wouldn't hestitate to use the newer style.
Here is some good info on different ways to measure pressure.
http://en.wikipedia.org/wiki/Pressure_measurement
Here is some good info on different ways to measure pressure.
http://en.wikipedia.org/wiki/Pressure_measurement
11-05-2010, 04:04 PM
#4
Thanks for the info. I keep on reading about "dummy" gauges and sending units, and I wanted to make sure I wasn't getting one of those. It seems like all of the aftermarket ones are the wide style, while the thin style is the OEM choice. I bought one of the thin ones, and I guess I'll see how it works.
11-06-2010, 12:05 PM
#5
I have done a little more research and, and what I have found is that over about the last 20 years, many manufacturers have been using "dummy" oil pressure gauges. It seems like the GenIII oil pressure senders/gauges are not in this group... they all seem to drive the gauge and give somewhat accurate readings. But many American vehicles, including Fords, run a switch and gauge combination that has pretty much two readings on the gauge: 1) normal oil pressure, whether it's on the high side or low side, and 2) no pressure at all. The thinner units, as pictured above, are only switches. As most of you know, the LS1 sender is still on the thin side, but it has a slightly longer/taller tube - this is an actual sender. Autometer sells one similar for about $100.
I know this is not really new news, but I looked into a variety of US and British manufacturers, and this is what I found.
I know this is not really new news, but I looked into a variety of US and British manufacturers, and this is what I found.
