Operating temps

[Mark Romans]

Actually Smokey's book  "Track Tech"  goes into some detail about coolant
temps.  Basically he says that running the higher temps makes more power on
less fuel and runs cleaner.  But that you must tune the engine to operate at
that temp with afr and timing, also it takes away any reserve cooling if you
are drafting or your radiator gets blocked.

I actually tried the cooler thermostat thing for a while.  The problem is
that with the ac on and ambient temps of 100+ degrees I couldn't keep the
car at the lower temps so I was fighting trying to tune the car to run right
at 160 deg F AND 220 deg F.  No can do.  Also keeping the coolant temp that
low prevents the oil from heating up enough to boil off contaminants and can
cause corrosion.  I put the car back to  195 deg thermostat and set the
timing and fuel to run at that temp.  I also put in a BE COOL radiator and
now it runs all the time between 185 and 210 (Max in traffic with ac on).
This is a tight enough span of operating temps so that I can optimize the
timing and fuel.

All this reminds me of the guys that are selling the Manifold air temp
relocation kits for the L98.  Look at the 165 hac from ECM guy and ask
yourself you much you are gaining,  answer NOTHING.  The L98 doesn't adjust
anything by manifold air temp. No timing adjustments, no fuel adjustments.

Just several years and hundreds of diacom and G-tech runs, not to mention
SAE findings.
Mark






>Well, that's what life is like when you're puttering around in a
>miniature Golf.  Just kidding.  But Dave Cooley is absolutely correct
>about the fan temps for GM cars.  One of the most common complaints of
>C4 Vette owners is that the fans kick on at too high a temp.  Coming
>directly from a factory calibration, the primary fan turns on at 109d
>C (228d F) and the secondary fan turns on at 113d C (235d F).  It's
>not uncommon for coolant temps to reach 240.
>
>To truly expand your boundaries, read Dave Vizard's report on the Meca
>Oiling Systems tests with reverse flow Propylene Glycol cooling
>systems.  Engine temperatures are raised from 190 to 260 d F, with
>compression ratios as high as 16:1.  What was found was that the
>engines make slightly more hp on less fuel.  Hard to believe?  Maybe.
>But it's good reading nonetheless.
>
>Maybe you should look into why your golf shuts down at 220.  I'm sure
>that VW doesn't want to pay for overheated engines, so they play it
>safe.  There's a huge difference between the emissions controlled
>warranty included world of production cars and the all out, balls to
>the wall life a race car leads.  Way too many considerations to say
>the shutdown temp on an imported European car is the gospel in engine
>operation.
>Just a few thoughts.
>Shannen
>