[T3] Clemmie's Invasion MPG, Joys & Troubles (temps)

[Phil Hof]

I don’t think I am too lean.  The A/F meter has me no higher than the mid-13s at normal altitudes.  My exceptional mpg was probably due to my keeping speeds under 60mph, closer to 55 most of the way.  The return leg was only 50mph tops.

I expect mpg to be in the high 20s at “normal” L.A. freeway speeds (70-75 mph).  This is what she has always done.  The wild card is the ethanol in today’s gas, so I can’t compare too finely.

I am measuring temps using a sensor normally mounted in the drain plate.  It is not installed there, though; it is in the line leading to the remove oil filter, using a tee fitting.  It is thus right out of the oil pump, pre-cooler.  Both gauge and sender are VDO.

I just checked it (quickly) with an IR thermo, after a short boulevard run of about 10-15 minutes.  It is nearly 100 out today.  The dash gauge read 200 but the IR thermo only read 180 in the area of the sensor and in the sump.  I’ll need to roll it up on ramps or blocks to get a really accurate aim of the IR gun at the sensor, but this first look tells me the gauge is reading about 20 degrees high.

So I conclude I was indeed overheating on the desert runs to/from the Invasion, but not by quite as much as I feared.  The pinging may have been timing-driven, finally made audible in the highest of engine temperatures.  That also drove temps up, no doubt.

My engine builder is not a fan of external oil coolers.  He says it adds so many leak/failure points that the reduced reliability is not worth it.  I am on the fence.  If she runs too hot then I have to do something, and with a temp and pressure gauge, I’ll see if I have a hose/thermostat problem pretty quickly.  And I’m halfway there with an external oil filter anyway.  I’ll sleep on it.  Anyone used these enough to recommend?

He also recommends, as an experiment, running racing gas for a tank or two, and see what effect it has on engine temps.  There wis a station with racing gas about 10-15 minutes away.  I may try that.

She’s shined up, running well, and hopefully has forgiven my abuse last weekend.
-Phil

> 
> ------------------------------
> 
> Message: 2
> Date: Sat, 25 Jun 2016 22:42:22 -0400
> From: "Keith Park" <topnotch at nycap.rr.com>
> To: <type3 at vwtype3.org>
> Subject: Re: [T3] Clemmie's Invasion MPG, Joys & Troubles
> Message-ID: <2E.CA.03712.8014F675 at cdptpa-oedge03>
> Content-Type: text/plain;	charset="us-ascii"
> 
> Your gas mileage is too good, IF you driving at sea level or close, high
> elevations will drive it up, if its running too lean it will run too hot, I
> usually choose a tad rich just to be careful
> 
> Where your measuring your temps?
> 
> Oil sump temps should never go above 225, 245 being TOO hot.
> Head temps should be in the 325-375 range.
> 
> Keith 
> 
> Topnotch Restorations
> topnotch at nycap.rr.com
> http://www.a383ina68.addr.com/radiorest/main.htm
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> ------------------------------