[Tom Vaught]

Charles,
Did you ever get your answer on the difference
between a High Volume and High pressure pump?
If not I will try and summarize:
For quite a few years the standard pump on a stock
Pontiac engine was equivilent to the M54C Pump.
(About 40 psi and XXX rated Gallons per min).
In the mid 60s, the factory increased the gear
size and raised the spring pressure and the 60 psi
oil pump was born. This pump had several major enhancements: A thicker cover (No more tripling up on the bottom covers). Higher pressure relief
spring (no more shimming the spring) and a bigger
inlet tube and more exposed screen area showing. (54C had small inlet hole and small diameter tube)
This pump was so popular with the Hi-perf people that the factory made it the standard pump. It
was truly a high volume pump upgrade over the 54C
due to the multiple changes. This was what Ken C.
was trying to say in his post.
When the 73-74 engines were on the dynos the SD
engines had quite a few failures,(per Tom Nell).
One of the fixes was to increase the pressure in the oil galleries. Pontiac had Melling make a
special spring and cap for this application but
the parts are virtually the same for all of the
other pieces of the pump. This is a High pressure
upgrade to the standard 54D pump and is not necessary on most pontiacs. Any time you order any pump from Melling or anyone else you normally
will receive the 54D pump as most engine/ vehicle applications are 1960s or later.

Subject number TWO!

The latest Ken and Tom Fight.

Have you ever noticed how we get a lot more posts
when Ken and I are arguing. Ken and I hardly ever
agree on anything. He complains quite often about
shoddy workmanship. When I take him to task for what I consider to be normal prep on an oil pump,
he gets upset with me.

I feel that he should not ignore basic engine building steps because the customer is a STREET
guy and not a RACE guy. In my mind this says that
he feels the normal STREET guys motor is not as important as his RACE motor guys. Just because the STREET guys only can afford off the shelf type
parts does not meant that you can't save him some
time and money by showing him how to prep a pump
or doing it for him at a small cost to him. If
you know there is a problem with a pump due to rust or crud and you still sell it to the STREET
guy without telling him about it or helping him
fix it, you are intentionally putting a failure
in his engine. I think a lot of guys would pay a
few bucks gladly to save major bucks on a STREET
engine failure at a later date. You have shoddy
manufacturing practices and also shoddy business practices. Just my opinion. Don't want a war,
don't want the guy on the STREET getting screwed
either. Tom V.