Pulse and Glide without the clutch... - Fuel Economy, Hypermiling, EcoModding News and Forum

ChopsQube · 07-12-2010, 11:12 PM

Something I started doing with this tank of gas is doing my P&G without using the clutch. It's easier and more convenient to me. I just push it out of gear as I ease off the gas, then once I drop to my minimum glide, I blip the throttle to rev-match and keep a little pressure on the stick and it simply pops back into 6th gear.

Do any of you do this too, or are you still using the clutch? Just curious.

dcb · 07-12-2010, 11:25 PM

I've been doing it without the clutch ever since my clutch broke

I will probably switch to EOC and bump starts after I replace the clutch.

bestclimb · 07-13-2010, 12:01 AM

I EOC and use the clutch to save wear on the starter.

Patrick · 07-13-2010, 12:18 AM

Quote:

Originally Posted by ChopsQube

Something I started doing with this tank of gas is doing my P&G without using the clutch. It's easier and more convenient to me. I just push it out of gear as I ease off the gas, then once I drop to my minimum glide, I blip the throttle to rev-match and keep a little pressure on the stick and it simply pops back into 6th gear.

Do any of you do this too, or are you still using the clutch? Just curious.

You're probably OK popping it out of gear without the clutch, but you might be burning up the synchros by not using the clutch going back into gear. If it were me, I'd use the clutch.

Old Mechanic · 07-13-2010, 07:19 AM

Clutch wear is minimal, while transmission rebuilds can get very expensive.

It might be OK to go to neutral at the beginning of the coast, but I would avoid trying the blipped throttle rev match when you reengage the powertrain. That would definitely require perfect rev matching to avoid synchro damage.

Especially for no mileage benefit.

regards
Mech

ChopsQube · 07-13-2010, 09:46 PM

Yeah, I must have had a lucky streak yesterday. I was able to rev-match perfectly every time and the shifter would drop right back in gear. Today on the other hand, I was either under-reving or over-reving almost every time, so I was just using the clutch to reengage, but still nudging it out of gear without the clutch. It was about a 50-50 shot today.

For now on, I'll be using the clutch to reengage.

99metro · 07-25-2010, 11:45 AM

My ex-step used to call that "feathering". If you do it right, you can shift into gears with just the force of one finger. Too many people "think" they can do it by jamming it in - big no-no.

There isn't an problem if you do it right, but takes a lot of practice to get the revs right for the speed and gear. Him and me are the only one's I've ever seen do it right.

SentraSE-R · 07-26-2010, 07:14 PM

Like the others said, no FE benefit from shifting w/o the clutch. But glad to see you're still experimenting with the mpg game, and handily beating the EPA estimates. You should be able to top 40 mpg easily on highway trips just by slowing down to 60 mph.

PaleMelanesian · 07-27-2010, 09:25 AM

It is a useful skill to have, just in case you have a clutch failure. Barring that, I see no reason to not use the great clutch that's right there.

Something else to consider: a starter is much easier to replace than a clutch. It might be worthwhile to sometimes use the starter instead of bump-starting. (I usually bump-start, still)