Peakster's Chrysler Thread

[Peakster]

Attachment 403

Okay, so the Chrysler isn't my car (it's my dad's), but I thought I'd make a thread for it since I'm just having a hoot with it...

To start things off, I just drove to the university using the 'assinaboine route'. I did P&G on local streets and 80km/h on the TC highway. Cold start too. Although the SG isn't calibrated for the 2.7L engine yet, guess what my trip was? 42.5 MPG! (super long coast aftering exitting the freeway) EDIT: trip home - 34.9mpg

P&G is my new friend with this car . The Intrepid coasts awesome ! probably 3 times better than the Geo (due to more weight & better aero?). I did some P&G on Lewvan drive, a 70km/h 3-lane road with traffic lights every kilometre or so. I got into the mid 40s even with the rush home traffic ! It was freaking awesome.

I also really like how the SG doesn't shut off during key-off routines. My P&G method is to accelerate to around 40mph (which doesn't take much time at all in this car), shut off the engine and coast to about 25mph (even less if there's the road is completely empty). The only real complaint I have is the lack of power steering. Not a huge problem while coasting at medium speeds, but it's a real workout when travelling slowly!

Maybe my Geo can stay at the shop for a little longer .

[Bill in Houston]

Something like a 200 gallon aquarium full of water should do the trick. :-)

Best mileage I ever got in my oooold 626 was a trip where I had about 700 lbs of stuff in the car and had to drive 50 mph on some little back roads...

[Peakster]

Originally Posted by theclencher

Ballast the Metro up to 3900 lbs and see how the coasting compares.

When I had the Geo loaded up with passengers going to Edmonton last January, I noticed it coasted much farther. The question is: would the increased coasting compensate for the extra fuel used to move the car?

I can't wait to fill the tank of the Chrysler to see how accurate the SG readings are.

[repete86]

The fuel use is only really increased when accelerating. Thanks to inertia, it might require less energy to keep it in motion giving you better mileage on the highway. My best tank was driving back from a week of protests in Miami with a friend and a few hundred pounds worth of zines in the back of the car.

[trebuchet03]

Originally Posted by Peakster

When I had the Geo loaded up with passengers going to Edmonton last January, I noticed it coasted much farther. The question is: would the increased coasting compensate for the extra fuel used to move the car?

That all depends on where you're driving For me - no... Almost all of my tanks are 100% city driving.... Keep in mind though - it takes quite some time to eat up those tanks

But on the highway -- I'll bet there's a "sweet spot" to balance increased rolling resistance, extra power necessary to accelerate etc Energy is conserved - but power is not

[Bill in Houston]

I think that lowered ride height (improved aero) is one of the main benefits of extra weight. Plus, I drive a little more slowly and carefully when the car if full of stuff.

[Peakster]

I took the Intrepid out on the TC highway going west From Regina to Moose Jaw (very flat road) and this is the FE laydown:

Temperature 16*C, winds SE @ 20km/h
Each FE reading was done after 2 miles of driving at the stated speed

40 mph = 32.3 mpg
45 mph = 34.9 mpg
50 mph = 35.7 mpg
55 mph = 32.7 mpg
60 mph = 29.9 mpg
65 mph = 29.4 mpg
70 mph = 29.2 mpg

I find it interesting that a): the mileage gets worse below 50mph (maybe due to the torque converter not locking?) and b): the mileage seems to plateau with speeds over 60mph. Evidence of good aerodynamics? It's pretty sad that the V6, 3600 pound Intrepid gets just a few less mpg's less than the Geo @ 70 mph .

[ELF]

Your mpg below 50 is weird, my sable which is fairly close to your car in weight and engine size will get around 45mpg at 40mph. My tc will lock up right about 35/ 36 mph. you can see a big drop in rpm when it locks.

[Peakster]

Originally Posted by ELF

Your mpg below 50 is weird, my sable which is fairly close to your car in weight and engine size will get around 45mpg at 40mph. My tc will lock up right about 35/ 36 mph. you can see a big drop in rpm when it locks.

Yeah, I notice the RPM needle moves quite a bit when (I think) the TC locks up. It's almost like an extra gear. My question: what's the benefit of not having the TC lock up? Why don't automobile manufactures make it lock up all the time (except when the automatic transmission shifts gears)?

[trebuchet03]

Originally Posted by Peakster

Yeah, I notice the RPM needle moves quite a bit when (I think) the TC locks up. It's almost like an extra gear. My question: what's the benefit of not having the TC lock up? Why don't automobile manufactures make it lock up all the time (except when the automatic transmission shifts gears)?

Some mfr's have the tranny go into lockup early.... It requires a more beefy system, but they exist... I remember my '93 SW2 did it

As for why not? In slower city traffic, going into lockup and then unlocking and then locking up again isn't so great in the heat, wear and tear departments. But when the roads are more open, and you're not constantly taking your foot off the pedal (and unlocking), it's not a benefit at all Lockup on hills isn't so fun either -- especially when there's not enough throttle to change gears (finding holes in logic programming) Additionally, a locked TC won't give you any torque multiplication

When I was driving an auto -- I got up to my lockup speed as fast (reasonably) as I could and then let off in the throttle so it would finally go into lockup... It is like another gear (shift wise).