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Old 04-20-2007, 08:45 PM   #31
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I will pulse and glide if I don't have anyone behind me, but it is too crazy of a way to drive if a person is behind you.
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2008 EPA adjusted:


Distance traveled by bicycle in 2007= 1,830ish miles
Average commute speed=25mph (yes, that's in a car)
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Old 04-20-2007, 08:45 PM   #32
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I will pulse and glide if I don't have anyone behind me, but it is too crazy of a way to drive if a person is behind you.
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2008 EPA adjusted:


Distance traveled by bicycle in 2007= 1,830ish miles
Average commute speed=25mph (yes, that's in a car)
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Old 04-21-2007, 06:07 AM   #33
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Quote:
Originally Posted by diamondlarry View Post
Metro, about what rpm's are you running when pulsing like this? If I'm figuring correctly(15 mph to 40ish mph), this would be a 3rd-4th gear pulse for me.
I usually max in the high 2000 RPM range in the burn.
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Old 04-21-2007, 06:17 AM   #34
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Quote:
Originally Posted by Peakster View Post
I shut off the engine at 50km/h, bump start in 5th gear @ 35km/h. I go into 3rd gear, accelerate from 35km/h - 40km/h, shift into 4th and accelerate from 40km/h to 50km/h.
What's your max RPM in 3rd or 4th at those speeds? I wonder if you're holding it a little too low.

I'm in 3rd gear up to 60-63 km/h. With the taller tranny and tires, my RPM is 25% lower than yours, which tells me you should be at 45-47 km/h before you shift out of 3rd if you were copying my approach.

And don't be afraid to use plenty of throttle in the burn - 1/2 of max TPS is no problem.

AH! Just thought of something else: this may be ScanGauge related. Doesn't your SG stop recording speed/distance data when you key off? And take a while to reboot when you key on again? If so your apparently lower MPG may just be a calculation error. That was the main reason I installed a kill switch - to keep the 12v always on to the SG.
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Old 04-21-2007, 01:31 PM   #35
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Quote:
Originally Posted by MetroMPG View Post
What's your max RPM in 3rd or 4th at those speeds? I wonder if you're holding it a little too low.
5th gear @ 50km/h is around 1500 rpm
4th gear @ 50km/h is around 1800 rpm
3rd gear @ 50km/h is around 2500 rpm

I usually don't pay attention to RPM, I just shift whenever the engine sounds buzzy. I've always thought that MPG is pretty much always better in higher gear rather than lower (eg. flooring the car and lugging it in 5th @ 50km/h returns ~28mpg while at the same speed in 4th, flooring it only returns ~22mpg)

Quote:
And don't be afraid to use plenty of throttle in the burn - 1/2 of max TPS is no problem.
I usually press 1/2 of the way down to the floor on the accelerator, or just enough for the engine not to lug in gear.

Quote:
AH! Just thought of something else: this may be ScanGauge related. Doesn't your SG stop recording speed/distance data when you key off? And take a while to reboot when you key on again? If so your apparently lower MPG may just be a calculation error. That was the main reason I installed a kill switch - to keep the 12v always on to the SG.
My SG does turn off during the P&G (or there's a medium pause before it calculates MPG again when the ice is off), but for the past several months the 'gallons used' indicator on the SG has been very accurate. So whenever calculate my MPG between fills (such as my sig) I take the miles traveled from the dashboard odometer (as the SG 'miles traveled' is always wrong whenever I CODFISH within the tank) and divide it by the 'gallons used' on the SG.

Perhaps a kill switch is in order. How does a person rig one up?
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Old 04-21-2007, 03:13 PM   #36
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Yup, my advice then is 2 part:

1) accelerate to a higher speed before shifting during P&G runs than you have been

2) the MPG calcs you're seeing are the reason you think P&G isn't working for you. The SG may well be calculating fuel used closely, but it's not recording distance traveled for a portion of your glide (until it reboots), and that's where the error is.

Do a search for kill switches. I did mine on the coil pickup wire (on the distributor); other Metroids have used the fuel injector signal wire (TBI = only 1 wire). I'd be inclined to do the TBI wire switch. Trying to remember who did theirs this way, but I can't at the moment.

Also, you want a momentary off switch, not an on/off switch. IE you press and hold until the engine quits, then release and you're ready to restart whenever.
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Old 04-21-2007, 03:24 PM   #37
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Quote:
Originally Posted by diamondlarry View Post
Metro, about what rpm's are you running when pulsing like this? If I'm figuring correctly(15 mph to 40ish mph), this would be a 3rd-4th gear pulse for me.
Whoops - just realized I didn't answer the second part.

15-40ish range is 2nd & 3rd gear for me - but remember, I've got the longer legs.
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Old 04-21-2007, 08:27 PM   #38
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Actually, I could almost do the 15-40 mph burn in 4th only.

Quote:
Do a search for kill switches. I did mine on the coil pickup wire (on the distributor); other Metroids have used the fuel injector signal wire (TBI = only 1 wire). I'd be inclined to do the TBI wire switch. Trying to remember who did theirs this way, but I can't at the moment.
Was it me you were thinking of?
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Old 04-22-2007, 05:10 AM   #39
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I was thinking of someone with a Suzukiclone who posted a picture.. May have been jwxr7... Or Skewbe.
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Old 04-22-2007, 10:35 AM   #40
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Is it normal for the ICE to idle higher when the car is in motion?
At least on my PT Cruiser, part of it has do with the power steering set-up. There is a sensor that detects PS load on the engine. It automatically adds fuel to increase engine RPM when the PS pump is engaged... Maybe its the same?
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