Mike -
Some points encountered while chasing overheating:
Did you close off the bypass hose from below the thermostat to the top of
the water pump? If yours has one.
My motor ('67 1275) is sensitive to timing changes as small as plus/minus 1
degree.
Temporarily run heater input air hose to vicinity of carb inlet to
determine if under hood air temps are the cause.
Best o' luck,
Clayton
At 05:05 PM 10/25/01 -0700, Mike MacLean wrote:
>Brian,
> Today I re-installed the 3 row radiator in the Bugeye because the
>technician
>at Evans Cooling where i bought the NPG+ told me I needed a 3 row
>radiator
>minimum with at least 1/2 inch wide tubes, which the stock Bugeye
>radiator does.
>He also told me to take out the thermostat and install a blanking
>sleeve, which I
>also did today. I took the car for a test drive, remember I'm using the
>S.U. H1s
>now. There was not much change, so I started to play around with the
>timing. An
>e mail from David Vizard said I probably am running to retarded and
>probably
>could advance it to aid in cooling. He also told me to time it
>according to
>performance and not timing marks as he has seen some timing marks off as
>much as
>10 degrees on "A" series motors. I advanced the timing 5 degrees to 10
>degrees
>BTDC and did another test drive. Overheating situation was no better,
>but idle
>was rough and it was hard to start when hot. Overheated at speed.
>O.K., so I
>retarded it 5 degrees form the Bugeye standard timing (5 degrees BTDC)
>to 0
>degrees. By now it was time to pick my son up from elementary school 12
>miles
>away, so off I went on another test drive and an errand. On the freeway
>it
>stayed at around 190 and just like when I advanced it, it would raise to
>200 at
>traffic lights, but when I got moving again, it would drop to 190 or a
>little
>lower. At normal timing of 5 degrees BTDC this is pretty close to the
>way it
>acts, but it does not come down after a traffic light so easily as it
>did on my
>last test drive today. My timing cover is from a later 948 or 1098
>engine so I
>can use a rubber seal instead of a felt one that originally came on the
>Bugeye.
>It has the 3 timing pointers like the felt seal cover for 0 degrees, 5
>degrees
>BTDC and 10 degrees BTDC. Could these pointers be off? Are some other
>markings
>in the timing gears or pulley be off? I'm going to play with carb
>mixture
>tomorrow with my Colortune because i just re-installed the carbs. No
>overheating-my Holy Grail. No Monty Python jokes, please.
>Mike MacLean-60 Sprite
>
>brian S wrote:
>
> > Mike,
> >
> > Just a thought for when you go back to the supercharger. Maybe some
>sort of
> > cool air intake to the carb. Much cooler outside air for the intake
>may help
> > with the overheating you're experiencing a bit. It would lower the
>intake
> > air charge, even taking into account that the s/c will raise it, it
>will be
> > lower than compressed underhood air. Lower intake charge,lower engine
> > running temp could possibly let you advance the timing a bit, allowing
>the
> > engine to run even a bit more cooler, (more cooler?is that right??)
>also,
> > NO??
> > Not that it is now but, Timing retarded too much = overheating?? No?
> >
> > This sound reasonable to all the experts out there? as I am not one of
>them.
> >
> > ;-)
> >
> > Brian S.
> > Bugeye under resto
> >
> > >>
> > >Having replaced my crank pulley this past week (George Folchi was
>kind
> > >enough to supply a new one to me) I decided to remove my
>supercharger.
> > >Maybe another time in the future I will play with it again, but for
>now
> > >it's back to the future with the SU H1s. I simply don't have time
> > >anymore for the fiddling around and all the adjusting associated with
>
> > >supercharging as I will be returning to work soon. George's
> > >supercharger worked quite well when set up correctly, but I'm just
>going
> > >back to the simplicity of S.U.s for a while.
> > >Mike MacLean 60 Sprite
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