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-   -   Pulse and Glide questions..Totally new to this (https://ecomodder.com/forum/showthread.php/pulse-glide-questions-totally-new-366.html)

Undie 12-20-2007 08:00 PM

Pulse and Glide questions..Totally new to this
 
Ok. I'm new here and this pulse and glide thing is very foreign to me, but I'd like to give it a try. I have a question,

When you shut off your motor do you bump start it or use the starter?

Are you not worried about excessive clutch wear? (or starter if you use that)

It is possible that this technique is just not for me because I have a lot of mechanical sympathy and am pretty much as interested in longevity of my car as I am with fuel economy. I put on a lot of km and I'd like my car to last a long time.
Thanks.

Peakster 12-20-2007 08:43 PM

When I did P&G, I always bump start the motor. I would let out the clutch just enough to lightly grab and start the engine. Give it a try sometime and see how you feel about it.

I gave up on P&G months ago because Winnipeg traffic is all accelerate like hell to get through the green light and slam on the brakes when it turns red. People get angry when there's even a slight amount of coasting on the streets. 35-mpg is the price I pay (Instead of 60+mpg P&Ging).

And yeah, my clutch is pretty worn. It doesn't grab until the final few millimeters of release.

MetroMPG 12-20-2007 10:03 PM

Peakster: that's what route selection is for ;)

Quote:

Originally Posted by Undie (Post 2692)
When you shut off your motor do you bump start it or use the starter?

Clutch start if I'm planning another pulse; key start if I'm coasting to a stop where I'm going to be waiting a while.

Quote:

Are you not worried about excessive clutch wear? (or starter if you use that)
Excessive, no. There's going to be some wear, but I figure it's less demanding on the clutch to spin up the motor compared to the wear from accelerating the car from a dead stop. Drivers who slip their clutches when downshifting are wearing them out faster than I am with P&G.

People with automatics are going to see more starter wear because they have no option.

A lot will depend on how good (technically) you are at it. Rough drivers are going to put more wear on the drivetrain in general.

When you get practiced at clutch starting, it's very smooth. I recently showed the technique to someone, and I had to say out loud when I was killing the motor & when I had clutch started it.

Another important tip: to restart, choose a higher gear for the bump than the one you'd normally be in for the current road speed. Then shift back down to drive. Makes it a lot smoother. And Peakster's right - you just lightly/partially engage the clutch to spin up the motor and immediately de-clutch again once it fires. Then select the proper gear as usual (rev matched engagement is best).

Quote:

It is possible that this technique is just not for me because I have a lot of mechanical sympathy
Understandable. I wouldn't recommend it to anyone who isn't 100% comfortable with the idea.

DifferentPointofView 12-20-2007 11:37 PM

^
I'm one of those people, one because I love my Jeep, and 2 because I'm still trying to undo the damage the old owners did to it. You don't EVER let the engine drive after 7500 miles without an oil change and no oil on the dipstick!!! They were such dumb retards. I also changed my fuel filter not too long ago and the fuel that came out was black. Spark plugs were recently changed cause the old ones had their electrodes worn so bad they were gapped over 2 times the factory gap, almost 3 times. I still need to replace some more needed maintenance, as well as an oil change needed in the next 300 or so miles. It may look like a sound vehicle, but when you buy a used J.E.E.P., Just Expect Every Problem ;)

Undie 12-21-2007 06:01 PM

Thanks for your answers.

'm pretty good at clutch starting, (I race motorcycles and you often have to do that if they have no starter)
I just know the more times you push the clutch in and out it has load on it and thats also put on bearings and they will just wear out faster. I can just see needing throw bearings or release bearings and having to replace them, which on a Subaru is expensive. So I was curious if this is something you factor in or even worry about.
I can see using this technique in a few places on the commute where I have a few long hills down and little short steeper hills upward on the way home. I usually take a different route home from work due to traffic being lighter. I tried it on the way home just guessing that I was supposed to clutch start and I can see that doing that regularly would probably pay off.

dissimilation 12-26-2007 04:20 PM

I just tried pulse and glide on my way to work this morning. I hadn't read this post or too much on the subject yet, but I guess I was doing it exactly right. I had the biggest grin on my face the first time I instinctually let off the clutch in fifth and the engine sparked back to life. The grin was from two things, one) how it came naturally to me without thinking and two) how smoothly it happened. I only did it on surface streets for the last mile to work, but jeez - I'm addicted. Can't wait to see what I can accomplish on my drive home tonight. I'm going to make a stop at gas stations before and after to find out.

One hang up in the process, I turn the ignition key to kill the motor - but then I have to turn it forward a click for my turn signals to work again and have it "cocked" for restarting. It's a bit awkward to reach for the key, is this where the Fuel Injector shut off switches I've heard about make the process more natural? What are the popular mods for improving the process?

(I'm using my 93 Civic DX HB, not the Metro Convertible at the moment)

metroschultz 12-29-2007 12:48 PM

I am also using key off/on again. i plan on putting a rocker switch on the dash near the wheel to kill the engine and the other half of the switch to restart w/ starter. currently this afternoon is for basic upkeep. New rear wheel bearings, and repair of the front spoiler. Note: don't let your friends borrow your car if they won't back into a parking space. S.

MetroMPG 12-29-2007 01:11 PM

I have my switch on the side of the gear shift knob. Since engine stop is usually accompanied by a shift to neutral for gliding, I figured it was better ergonomics.

metroschultz 12-30-2007 02:43 PM

Good point, I'll have to keep that in mind when i am designing and instaling mine. Second note: make sure the tech puts the dust cap back on your rear hubs after State Insp, Now I know why my new bearings failed so quickly, S,

Mike 01-08-2008 12:22 PM

Quote:

Originally Posted by MetroMPG (Post 2698)
When you get good at clutch starting, it's very smooth. I recently showed the technique to someone, and I had to say out loud when I was killing the motor & when I had clutch started it.

He speaks the truth.


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