Pre-heating the incoming air may not be as much a problem on MPI's as much
as carbed and TBI engines. In those engines the atomized air can
de-atomize in a cold manifold and cause stumbling and rough running until
the manifold heats up. The preheater warms the incoming air and helps
prevent this problem.
I suppose in a MPI system the fact that this atomization does not occur
until the intake valve area this is not a problem but you are still drawing
very cold air for the first couple of blocks until the engine compartment
warms up.. Actually, the mod that effects the warmup even worse is
headers. Have not seen any new generation headers but I'm pretty sure you
will lose the exhaust pre-heater thermostat on the drivers side when you
install headers. This gizmo closes when cold and forces exhaust through
passages in your intake manifold. Again it is to warm the manifold up
quickly to aid in atomization. So if you have both mods on a vehicle that
sees cold winters, you could have and engine that will warm up too slowly
and stumble around until warm.
And yet another are the Chips that require a 160 degree thermostat. Great
in the sun belt but probably not too healthy in the snow belt.
Anything I have built up over the years was only driven in the summer so
it's not a problem but if it's your daily driver and you live in colder
climates the keep the old air cleaner and use it in the winter. These
engines are designed to operate at much higher temps that the old mussel
cars I played with in the 'GOOD OL DAYS'.. Computers get really confused
if the engine does not come up to temperature.
BTW Has anyone used the HP chip in the winter (snow, ice)??
If so, how well does it work?
> Hey Brian, can you expound on this a little more?? Your post was a little
> vague, and I'd like to know more about the need for pre-heating...why you
> need it, what it is, and why it can be detrimental to the engine if you
> don't have it... Thanks!
>
> Ciao!
>
> Ned Vogler
> (nvogler@rghosp.chime.org)
> '96 Dakota SLT V8 5-sp 4x4 Club Cab
> Gibson 3" Catback Exhaust/MPI FIPK-clone
> MSD Ignition & MPI Super Street TBI soon!
>
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:07:40 EDT