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Michael,
When we developed and tested the Chrysler engines
in the 1950's and 1960's we did it with a tetra ethyl lead additive (3 cc's
per gallon I think) in the gasoline. It worked - in fact the engine relied on
the lead deposits to avoid valve seat wear at high engine HP outputs. (Wide open
throttle at high engine speeds results in high valve temperature and high speed
valve action.)
Young engineers - such as myself - did not know
that lead was providing this benefit until we started testing engines with "no
lead" gasoline. Valve seat recession during testing due to wear required us to
harden valve seats or add hardened inserts to production engines to use
unleaded gasoline. You probably remember that the auto and petroleum industry
used a lead additive - until it was banned - because it was the cheapest way to
produce gasoline with the octane rating that we wanted.
I don't know what happens to valve seat wear when
you add Marvel Mystery Oil or ATF to the gasoline. I use am STP Lead Additive in
the gas tank of my old cars but they are driven so few miles - and usually below
60 MPH - that I doubt that it makes any difference. I only do it because I have
personally inspected durability test engines (with around 1,000 hours operation)
with more than 1/4" of valve seat wear due to testing with unleaded fuel. If I
ever have the engine rebuilt in my 1968 Dodge Charger I will have hardened valve
seat inserts added.
Burt Bouwkamp
---- Original Message -----
Sent: Monday, October 29, 2007 1:01
PM
Subject: RE: IML: Lead additive
I just bought a
bottle of Lead Additive at Advance Auto, which says on the bottle ?for older
cars which need leaded gas?. Anyone have any experience with this
product?
I guess my choices
for the 1952 Imperial are: Marvel Mystery Oil, ATF, or this stuff. Online
voting begin!!!
Seriously though,
thanks,
Michael
Alexander
From:
mailing-list-owner@xxxxxxxxxxxxxxxx
[mailto:mailing-list-owner@xxxxxxxxxxxxxxxx] On Behalf Of Gary Wilson
Sent: Thursday, October 25, 2007 10:01
PM
To: mailing-list@xxxxxxxxxxxxxxxx
Subject: Re: IML: Recession Unleaded Gas:
MMO vs. ATF
I don't know about
running a qt of oil thu the tank but ATF works real well because it is a high
detergent and helps coat the valves seat like leaded gas use to
do.
----- Original
Message -----
Sent: Thursday,
October 25, 2007 6:17 AM
Subject: IML: Recession
Unleaded Gas: MMO vs. ATF
On
my 1956 Imperial w/354 Hemi/Torqueflite 3 speed combo, I run a Marvel
Mystery Oil blend through the fuel tank at every fill-up according to the
specs on the bottle and have had great luck with it [I use it as well in the
motor oil] and change the oil quite often, every 1500 miles. I wonder,
though, if it is providing the same degree of 'engine maintenance' that the
ATF does/would do with a periodic run through. Any
thoughts?
In a
message dated 10/25/2007 9:03:11 A.M. Eastern Daylight Time,
randalpark@xxxxxxx writes:
like the idea of
running a quart of oil through the gas once in a
while. I have found
that it does improve performance.
Paul W.
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