Timing in closed loop
12-19-2007, 02:13 AM
#1
Timing in closed loop Increasing the timing in closed loop (cruise/around town) to get better gas mileage and run TR6 plugs gapped at .040 to cool the combustion. What are your thoughts on this working?
My car is a M6 and has a lid, cutout, longtubes w/ no cats ORY, and all the free mods.
It has not been tuned yet because there is no where in my area to have it dyno tuned. Just trying to get better gas mileage around town.
Also what are everyone's opinions on the LSXtune.com - mail order tune?
My car is a M6 and has a lid, cutout, longtubes w/ no cats ORY, and all the free mods.
It has not been tuned yet because there is no where in my area to have it dyno tuned. Just trying to get better gas mileage around town.
Also what are everyone's opinions on the LSXtune.com - mail order tune?
12-19-2007, 09:04 AM
#4
Moderator
iTrader: (11)
Join Date: Mar 2002
Location: East Central Florida
Posts: 12,604
Likes: 0
Received 6 Likes
on
6 Posts
Increasing timing works to a point but when the
crank is moving slow, you have an "opportunity"
to push the timing to where the pressure pulse
makes no contribution but heat, and cools by the
time the crank has rolled around to maximum
leverage. Burn time varies a lot with mixture and
pressure (following MAP / cylinder air). It's all cut
and try. Not exactly mail order tune territory.
And the "feedback" (MPG by the tankful) is a
mighty slow process for cut-and-try work. Though
if you were logging, maybe looking at acceleration
vs MAP at low throttle for a few timing positions
across the RPM band might give you a decent
indication of efficiency. Lot of messing around, to
get anything scientific going.
Relative to stock you can probably stand some
more. Just can't say, how much will optimize it for
your motor, weather, local gas blend etc. Maybe
give it +4 degrees and see. But I bet you gain more
from increasing tire pressure and cleaning out the
trunk.
crank is moving slow, you have an "opportunity"
to push the timing to where the pressure pulse
makes no contribution but heat, and cools by the
time the crank has rolled around to maximum
leverage. Burn time varies a lot with mixture and
pressure (following MAP / cylinder air). It's all cut
and try. Not exactly mail order tune territory.
And the "feedback" (MPG by the tankful) is a
mighty slow process for cut-and-try work. Though
if you were logging, maybe looking at acceleration
vs MAP at low throttle for a few timing positions
across the RPM band might give you a decent
indication of efficiency. Lot of messing around, to
get anything scientific going.
Relative to stock you can probably stand some
more. Just can't say, how much will optimize it for
your motor, weather, local gas blend etc. Maybe
give it +4 degrees and see. But I bet you gain more
from increasing tire pressure and cleaning out the
trunk.
12-19-2007, 02:34 PM
#5
[QUOTE=TTA1437;8332247]and run TR6 plugs gapped at .040 to cool the combustion.
??? Run TR6 plugs at a closer gap to cool the combustion? There is enough heat dissipation through the aluminum heads, you actually want to keep thermal temps on average in order to have complete combustion otherwise you will not be getting a full burn thus resulting in fuel out the tail pipe. This will hurt fuel economy not help....
??? Run TR6 plugs at a closer gap to cool the combustion? There is enough heat dissipation through the aluminum heads, you actually want to keep thermal temps on average in order to have complete combustion otherwise you will not be getting a full burn thus resulting in fuel out the tail pipe. This will hurt fuel economy not help....