[Mgs] 1972 MGB Timing

[Paul Hunt]

No, I'm correct.  Whilst if the timing is retarded you will get higher running
temps as more of the energy in the fuel is converted to waste heat rather than
forward motion as the piston is too far down and the gasses have already
expanded too much.  The same thing happens if you advance the timing *too
much* (as I said before).  In this case more of the energy is expended while
the piston is still moving upwards, and again becomes waste heat, as it cannot
be used to push the piston down until it has passed TDC.  This is only likely
to happen in low compression engines over any period of time, in high
compression you will get violent pinking if not detonation to (hopefully)
alert the driver to the situation.  With ideal timing you get maximum
conversion of energy to forward motion, and the least amount to wasted heat.

I don't see why you differentiate between coolant temp and exhaust temp, since
it has to come out of the combustion chamber which is surrounded by coolant an
increase in exhaust temp will also cause an increase in coolant temp.

PaulH.
  ----- Original Message -----
  From: Richard Ewald
  To: Paul Hunt
  Cc: Daybell7 at aol.com ; mgs at autox.team.net
  Sent: Monday, August 04, 2008 3:23 PM
  Subject: Re: [Mgs] 1972 MGB Timing


  If you are referring to coolant temps, then this is incorrect.  Advancing
the timing decreases coolant temp.  If you were referring to exhaust gas temp
then you would be correct.
  Rick


  >> if you start advancing the timing too much to try and get more power
*that* will cause high running temps,