Actually, the lack of thermostat sounds right.
Or, take the thermostat, knock out the central pieces, and just leave the
outer ring. That seems to be the SOP for a racing Spit.
At least, for the 1147. Not sure if that carries to the 1296 too.
Basically, you want more flow, but of course you also want it to be cool
flow. Some years back I was having an overheating problem -- as in, it would
get hot really quick; one autox run would get me up to 210+ and it would not
cool quickly, so it would sometimes take me two heats to get in four runs. I
was constantly spraying the radiator from a waterspray bottle. A friend
suggested rodding out the radiator. Took the rad to a radiator shop where
they popped off the top and bottom and ran a rod through the vertical tubes.
Mine was so clogged, they could not even get the rod through a couple of the
tubes, but it still made such a remarkable difference that I can sit and
idle for long periods now without overheating. And I make all my runs
without delaying the event. Back to back runs are no problem. Sometimes I
come off course and the temp is at 200, and a few minutes later (with the
engine off) it percolates up to 220, but as soon as I hit the key again and
get water flowing it drops almost immediately to <190. And I haven't brought
the spray bottle along since. (My temp pickup, BTW, is right in the
thermostat cover, and the radiator is a stock Mk. I unit).
--Rocky
----- Original Message -----
From: "Mark J Bradakis" <mjb@autox.team.net>
To: <fot@autox.team.net>
Sent: Saturday, July 12, 2003 2:01 AM
Subject: Not Cool
> So it has been 100+ the last few days here in Salt Lake, yuck. About this
> time last year you may remember I wrote about a British Motor Club of Utah
> drive where I ended up putting along the interstate in a Spitfire Mark 1
> during the hottest part of the hottest day ever recorded in the valley.
> I won't be doing that this year.
>
> What I will be doing is going to an autocross in the red racing Spit.
Last
> week the water temp was hovering around 220 F, though the oil temps stayed
> around 150. This sunday promises to be hotter than last sunday, so I'm a
> bit concerned about cooling. I popped off the thermostat cover on the
early
> 1296 motor, and found out there was no thermostat. No problem, I'll make
a
> restrictor plate, with the recommended, uh, well, err, I seem to recall
> that 5/8" was the proper size orifice, but I can't find any info in my
> notes. Does a 5/8" hole in the restrictor plate sound right to other
> Spit racers?
>
> mjb.
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