Load based driving techniques?

[user removed]

When I leave my house with a dead cold engine, I have .3 miles to a left turn at the 7-11 on to route 143. The first stop is .1 with .2 between. I have seen the average MPG actually increase slightly using P&G (engine on coast because of AT) before I get to that .3 mile stop sign to turn left on a 4 lane non divided 45 MPH route 143. It changes to 55 MPH about .4 mile after the left turn. I can usually get back to my average before the cold start by the time I have travelled 3 miles.

regards
Mech

[ps2fixer]

I have done a little more "playing" with P&G on my car and load based take offs. Seems my results favor P&G vs steady speed at cold start, and taking off fairly fast (~75-80% load via scan gauge) has been helping my average mpg instead of taking off lightly at around 60% load (~50% is steady speed @ 45mph).

[kennybobby]

Originally Posted by ps2fixer

I have done a little more "playing" with P&G on my car and load based take offs. Seems my results favor P&G vs steady speed at cold start, and taking off fairly fast (~75-80% load via scan gauge) has been helping my average mpg instead of taking off lightly at around 60% load (~50% is steady speed @ 45mph).

Like 85-90-95-100%. The FI controller goes open loop based upon the TPS going to WOT--is that when the scangauge reads 100% ?

It doesn't seem possible that 45mph ss would be 50% load does it? The throttle is just slightly cracked open at that condition.

[ps2fixer]

Originally Posted by kennybobby

Like 85-90-95-100%. The FI controller goes open loop based upon the TPS going to WOT--is that when the scangauge reads 100% ?

It doesn't seem possible that 45mph ss would be 50% load does it? The throttle is just slightly cracked open at that condition.

Correct, 45mph is slightly cracked open, just above idle (~4.0 is idle, 45mph for me is 6.6 and WOT is ~14.4).

The load isn't the max ability of the engine (mine being ~117hp), but the max HP @ the given RPM (~1500 in my case).

I don't watch my TPS readings, but I'm pretty sure I never go past 25% open, but I keep my RPM as low as possible with the auto trans.

[RdRnr]

Originally Posted by mjspiess

I have my aftermarket cruise control receiving info from a Ford MAP sensor rather than my VSS & it drives with load automatically. I set my cruise at 55 MPG & will maintain speeds of 60-65 MPH on flat road, drop to 53 MPH up hills & up to 76 MPH down hills.

Great idea! I have been thinking something like that would be ideal.


So, when I try DWL, I slow down on the uphills. But how slow should I let it go? As slow as is comfortable in 5th? Is it better to downshift to 4th and keep RPM up?

[cbaber]

In my car a higher load like 80% in 5th gear at a very low RPM yields better MPG than a lower load like 65% at a higher RPM in 4th gear. Basically you want to be in the highest gear possible always. Lower RPM is better at the same speed. Don't let you speed drop too much. If you do so, you have to apply higher loads downhill to gain back speed. I only let my speed drop 5-7 mph going up a hill on the highway. So for example I target 60 mph on the highway. Up a hill I pick a load that slowly lowers my speed from 60 to 55 by the time I reach the top. At the top I can reduce the load and slowly add speed on the way down until my next hill. On flat ground I maintain 60 mph.

[RdRnr]

Thanks. I'm probably letting my speed drop over 10 MPH on some of the longer and steeper climbs. Seems likes it not lugging. I have to climb many hills which is probably really hurting my MPG. I'll be getting one of those instantaneous MPG gauges soon so I'll be able to see exactly what's going on . . .