In a message dated 07/09/2005 8:57:49 PM Pacific Standard Time,
stiker2126@yahoo.com writes:
You probably just need to lean it out more.. and
retard the engine if you want better fuel economy..
IE: set the timeing for like 14 or 15 degrees BTDC
fuel will burn longer in the cylinder.. yah you wont
have as much power but to gain someplace ya gotta give
somewhere else... I had a choke cable hooked up to my
dizzy on my big buick with the 307 V8 in it so i can
sit inside the car and set it for race or gas
mileage.. :P
14-15 degrees BTDC is more advanced (assuming we're talking idle, not full
advance), not retarded, and that's more than I'd recommend. If you get too
much advance the engine starts fighting itself, since by advancing you're
igniting the mixture before the piston is at the top of its stroke. The other
thing to remember, and I've seen this a LOT at the shop, particularly with ZS
carbs, is that too lean will get you worse mileage/emissions. You can get a
lean misfire that's very subtle, but it makes a lot of difference, both in
driveability, and on a gas analyzer. The stock settings work pretty well in
general, assuming the engine is stock, but giving some advance on the cars
that
timed ATDC seems to make a little better power, and they definately run
cooler, but I generally try around 2-4 degrees before as a starting point.
just a couple cents worth...
Bill J
_www.sportscarslimited.net_ (http://www.sportscarslimited.net/)
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