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what you guys think? I put that last pargraph myself ;) feel free to fix my mistakes or grammarical errors!

http://en.wikipedia.org/wiki/Manual_transmission_driving_technique#Starting_the_vehicle_without_an_electric_starter


To start the car smoothly with the clutch, depending on speed its best to start in the higher gear so that engine revs won't soar too high when coming back alive again. Fuel economy pros use this technique to turn off their engine then putting the shifter into Neutral when acceleration is not needed, and then when a lower speed has been reached (say 30 mph or 50km/h) then one would attempt to restart the car with the clutch in 5th gear, since this method is much less harsh than turning on the engine with the key. One would have the clutch disengaged (clutch pedal in) and then from Neutral slide it into 5th. Then as you let rengage the clutch (slowly releasing to the friction point) you will feel it gripping the engine. Immediately let off the clutch pedal till the engine starts firing its cylinders and then right away press the clutch again to avoid aftershock. If done correctly within the second, the clutch should absorb any NVH (noise, vibration, harshness) and engine revs should rise to about 1100 rpms. If engine fails to start try a lower gear, but remember the lower the gear, the more clutch you need to absorb the greater aftershock. Engine revs could be higher during a bump start like 1500 rpms or 2000 although you want to keep these revs as low as possible in order to reduce wear and tear on the engine (rev too low and the engine won't come back on, one must know which gear to start with so that NVH is controllable for all speeds... in this case its harder to control as your momentum decreases). As the revs fall and settle to idle, one should rev match into the appropiate gear and then accelerate their way to desired speed (usualy 40mph or 70km/h before areodynamic losses are prevalant) and then repeat for maximum fuel economy. I suggest refining this technique before attempting to use in real world driving situations as if fallen to the wrong hands can be deadly (like speeding). A master with this technique can recall the engine within half a second and start accelerating as soon as that second is done with no NVH to either the driver or the passengers. And the mileage increases are reported to beat EPA highway estimates in the CITY. If one hasn't noticed why not just coast in Neutral? Simply because as your momentum decreases, the same amount of fuel used to keep the engine running won't be worth it as opposed to coasting with the engine off and mileage is still increased even at very low speeds. There is no payback for fuel coasting with the engine off as opposed to coasting with the engine on in Neutral. In Neutral one has to be travelling at higher speeds to gain the mileage benifits of coasting (since when one is in gear, engine braking prevents the car from travelling far with just momentum), but with the engine off that rule is broken and mileage soars upward at any speeds. Its just a matter of learning how to turn on one's engine when they need it the most as well as maintaining safety, passenger comfort and not overdraining your 12 volt battery.

:D

Phil;
Nice article. :)

Hi Phil:

___A very nice description! Especially the part about 1,100 RPM’s … I wonder where I hear that before ;)

___Can you change the title to “Clutch start of a manual transmissions equipped automobile”? When I read the threads title, I thought it was going to describe driving a manual, not clutch or “Bump” starting a MT equipped automobile?

___Good Luck

___Wayne

Also like to add:

- when your engine is off you will not have the assisted power steering, so at lower speeds be sure to use both of your arms to steer.

- turn off any electrical loads while having the engine off, remember that the battery is very fragile and if you have a monitering tool (like scanguage) you can moniter the voltage. State of charge as follows:

12.9 = 100%
12.7 = 75%
12.4 = 50%
12.2 = going to be discharged soon

- when the car is off the voltage should be between 11 and 13 with 11 being dangerously low (remember decimals play a big role here) so be sure to top off your battery before shutting off the car for good.

- To improve coasting ability, I recommend pumping your tires to max sidewall pressure. Your aiming for high fuel economy right? You shouldn't worry about a plush ride at all, in fact you'll hardly notice if you plan to abuse this technique. What you will notice is that what you normally do to keep a constant speed will still be constant thanks to the added rolling ability

- And remember try not to burn too much clutch! Smoothness is key if you don't want things falling apart even though you are getting more than 40 mpg in the city. But improve upon your personal ability to recall the engine too because if you baby your clutch too slow the engine won't turn on. Smooth then fast is key because having your engine off for long periods of time will probably knock you into thinking that you can accelerate onward after you have reached a lower set speed. Just remember never to panic and give yourself a few seconds ahead of time to turn on your engine, as you get better those few seconds can be just one.

I'll add more if my mind allows it.

Hi Phil:

___Not bad! Do not forget to mention that at higher speeds, a FAS does not really increase steering wheel torque needed to make small or even a large correction. It is when you get down below maybe 15 mph that you start the brute strength scenario in most automobiles. The Accord is a bear at 5 mph or less but at highway speeds, you can hardly tell you lost power steering assist. With the EPS based automobiles, you can remove a fuse to disable power steering altogether which I did in the Insight. Its weight and tire friction were easily bearable at extremely slow speeds. I actually disliked the over-boosted EPS at slow speeds so I pulled the fuse and drove without EPS altogether for the last few months of my time with her ;)

___About the brakes during a FAS … 3 - 5 pumps and they are history in most automobiles.

___Voltage of the 12V … Tom has a huge stereo load as well as a 12V monitor in his HCH-I and IIRC, 11.2 V is when he said he was at drop dead and never re-start area? I have been down to the no start area under multiple FAS’ with the lights on during nighttime hours in the Accord but I do not have anyway of monitoring the 12V just yet. Watching the internal and external lights is about the best way to know when you are getting close if you are not setup to watch the actual V off the 12V in my experience. As it warms up, your 12V’s cap increases mightily (> 2X’s at 70 degrees F vs. 20 degrees F or below) and that might be something you want to mention as well?

___Good Luck

___Wayne

hm i was talking to my teacher and he said that anything below 8.5 volts is when the battery is useless. Anything above that you might have a chance of starting your car again.

Now that a question came to mind, can you bump start in reverse? Since my drive way slouches up and then kinda turns a bit (most messed up driveway i ever seen imo) I'd back into it so I can Face out but boy backing up is not worth all that clutch! So if I can bump start while rolling back I don't need to key on anymore!!!!!!!

More battery power for me! But before I do it, I'd like some opinion please ;)

I rarely if ever bump start going backwards.

I dont worry about my battery at all. None nada. Ive never worried about batterys. I always get 4 to 6 years out of my batterys. Living in Oklahoma may help, but didnt have any problems with them in Colorado either.

I did a fas about 5 miles when we left the grand canyon. It was night by then. Had the headlights on, radio cranked, lappy pluged into the inverter, scangauge reading in the high 90's for current mpg and it was in the high 30's F temp wise. It was only one out of maybe three hypermiling moves made while on that trip. Only batterys Ive ever had fail before there time are GM's delco junk and O'riley Auto parts in house line of batterys.

hm i was talking to my teacher and he said that anything below 8.5 volts is when the battery is useless. Anything above that you might have a chance of starting your car again.

Now that a question came to mind, can you bump start in reverse? Since my drive way slouches up and then kinda turns a bit (most messed up driveway i ever seen imo) I'd back into it so I can Face out but boy backing up is not worth all that clutch! So if I can bump start while rolling back I don't need to key on anymore!!!!!!!

More battery power for me! But before I do it, I'd like some opinion please ;)

Reverse is typically a very short gear. Bump starting would give the driveline quite a jolt. I don't remember ever doing it.

Reverse is typically a very short gear. Bump starting would give the driveline quite a jolt. I don't remember ever doing it.


you sir are correct, i'll just use my usual face out then key on method, although bump starting is so much smoother than a cold key start. Maybe I should learn how to back up a hilly driveway without using any clutch? Hm that jolt was painful as well I think I grinded it a bit, people accross the street was giving me the look again ;(

Phil,
Congrats on your hypermiler status. you have earned it!

I have clutch started in reverse before and it wasn't too bad. I started to let the clutch out to where I felt the beginning of resistance then very quickly let out just a tiny bit more and VERY quickly shove the clutch back in. I usually clutch start in a forward direction though.

Phil,
Congrats on your hypermiler status. you have earned it!
not good enough knowing that your car beats mine :D I think your car really sparked the, "if him, why not I?" kind of saying since your driving conditions and vehicle were very similar to mine. At that moment I began to allow myself to work for progress and competitiveness that no one else can touch unless they are as determined as you were. That spirit alone was enough to convince me to finally drop how I was learned to drive and began teaching myself new ways to let the road drive the car and not drive the car on the road.

Couldn't have done it without the help of the whole community of cleanmpg and the dudes at gassavers. What a beautiful community we are creating, one that we can take a wiff of big air and go, "Yum." :D

Interesting times ahead. :p and as for the reverse... maybe one more try.... and i'll edit this post to let you guys know if its really possible.