Go Back   EcoModder Forum > EcoModding > Hypermiling / EcoDriver's Ed
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 09-18-2013, 10:41 PM   #11 (permalink)
Master EcoModder
 
Join Date: Apr 2013
Location: World
Posts: 385
Thanks: 82
Thanked 82 Times in 67 Posts
Quote:
Originally Posted by RobertISaar View Post
since it's relevant... thought i've had about bump-starting lately is putting the throttle on the floor(or at least, opened significantly) before letting the clutch out to prevent the instant engine braking that would happen with a closed throttle plate when going from 0RPM to whatever the engine would spin up to when in gear.

seems like it would be less strenuous on both the clutch and engine.
Maybe. Once the engine stops spinning though, the inlet manifold very quickly fills with air at atmospheric pressure. Every time you start the engine, it is, initially at least, in an equivalent state to wide open throttle.

It's (throttle open) easy enough to try anyway.

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 09-19-2013, 03:15 PM   #12 (permalink)
Master Novice
 
elhigh's Avatar
 
Join Date: Jan 2008
Location: SE USA - East Tennessee
Posts: 2,314

Josie - '87 Toyota Pickup
90 day: 29.5 mpg (US)

Felicia - '09 Toyota Prius Base
90 day: 49.62 mpg (US)
Thanks: 427
Thanked 616 Times in 450 Posts
Fuel cutoff solenoid prevents pulling unnecessary fuel through the lines during key-off engine revs. I don't know how old your carbureted car would have to be to lack a cutoff solenoid; I think Toyotas had it in the 70s.

But it makes a huge difference to let it run down to idle and run there for a second or two before keying off. Turning off while still at high revs pulls too much fuel through unburned, and it almost guarantees a nasty backfire at the next key-on. And if you look back through my history, you can see where a backfire blew my (admittedly cheap) muffler wide open. So I spare a few milliliters of fuel to prevent that. It's worth it.
__________________




Lead or follow. Either is fine.
  Reply With Quote
Old 09-19-2013, 07:02 PM   #13 (permalink)
Master EcoModder
 
Join Date: Apr 2013
Location: World
Posts: 385
Thanks: 82
Thanked 82 Times in 67 Posts
Causing the backfire was sport in my (misspent) youth. Some of the responses of bystanders were amusing until I considered that, given returned vets and gun massacres, they could have been genuinely in fear for their lives.
  Reply With Quote
Old 09-19-2013, 07:37 PM   #14 (permalink)
Not Doug
 
Xist's Avatar
 
Join Date: Jun 2012
Location: Show Low, AZ
Posts: 12,186

Chorizo - '00 Honda Civic HX, baby! :D
90 day: 35.35 mpg (US)

Mid-Life Crisis Fighter - '99 Honda Accord LX
90 day: 34.2 mpg (US)

Gramps - '04 Toyota Camry LE
90 day: 35.39 mpg (US)

Don't hit me bro - '05 Toyota Camry LE
90 day: 29.44 mpg (US)
Thanks: 7,225
Thanked 2,217 Times in 1,708 Posts
Quote:
Originally Posted by Occasionally6 View Post
Causing the backfire was sport in my (misspent) youth. Some of the responses of bystanders were amusing until I considered that, given returned vets and gun massacres, they could have been genuinely in fear for their lives.
In Phoenix, when the walk sign comes on at intersection, there is some clicking sound which, to me, sounds like a machine gun.

I first heard it at the VA.
  Reply With Quote
Old 09-20-2013, 05:30 PM   #15 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,571
Thanks: 0
Thanked 1,627 Times in 1,452 Posts
Some folks believe that bump-starting an engine with carburettor is safer than doing the same in one with EFI.
  Reply With Quote
Old 09-20-2013, 08:36 PM   #16 (permalink)
Exceptional Member
 
YukonCornelius's Avatar
 
Join Date: Jan 2011
Location: Pennsylvania
Posts: 166

Crapolier - '98 Chevrolet Cavalier base
90 day: 34.81 mpg (US)

05 CTS-V - '05 cadillac cts-v
90 day: 33.01 mpg (US)

95 Accord - '95 Honda Accord
90 day: 38.06 mpg (US)

11 CTS-V - '11 Cadillac CTS-V
Thanks: 27
Thanked 15 Times in 14 Posts
With my cts-v I have do a quick up down with the clutch pedal to get the smoothest kick start. A bump start should do no wear. Your using the clutch to rotate the engine internals, normally your using the clutch to move an entire vehicle.
__________________




Don't know why it says 00, it's a 95
374,000 miles and tired.

Last edited by YukonCornelius; 09-20-2013 at 08:42 PM..
  Reply With Quote
The Following User Says Thank You to YukonCornelius For This Useful Post:
elhigh (09-23-2013)
Old 09-21-2013, 06:07 AM   #17 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,571
Thanks: 0
Thanked 1,627 Times in 1,452 Posts
Quote:
Originally Posted by Lbar View Post
With my cts-v I have do a quick up down with the clutch pedal to get the smoothest kick start.
By "kick start" you mean starting with the vehicle still in motion after an EOC?
  Reply With Quote
Old 09-21-2013, 01:55 PM   #18 (permalink)
Exceptional Member
 
YukonCornelius's Avatar
 
Join Date: Jan 2011
Location: Pennsylvania
Posts: 166

Crapolier - '98 Chevrolet Cavalier base
90 day: 34.81 mpg (US)

05 CTS-V - '05 cadillac cts-v
90 day: 33.01 mpg (US)

95 Accord - '95 Honda Accord
90 day: 38.06 mpg (US)

11 CTS-V - '11 Cadillac CTS-V
Thanks: 27
Thanked 15 Times in 14 Posts
Quote:
Originally Posted by cRiPpLe_rOoStEr View Post
By "kick start" you mean starting with the vehicle still in motion after an EOC?

Si senior. I should have said bump start, the motion I use with my leg would probably look like I was kick starting something.
__________________




Don't know why it says 00, it's a 95
374,000 miles and tired.
  Reply With Quote
Old 09-24-2013, 06:36 AM   #19 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,571
Thanks: 0
Thanked 1,627 Times in 1,452 Posts
Kick-start in this case actually makes sense

BTW once I've considered to work around a boat-like supplementary pull-string starting setup for an old Pontiac Trans Sport which was having constant starter failures.
  Reply With Quote
Old 09-24-2013, 12:57 PM   #20 (permalink)
Master EcoModder
 
Join Date: Jul 2008
Location: NY state
Posts: 501

XJ Cherokee - '00 Jeep Cherokee Sport
90 day: 12.96 mpg (US)

FoFO - '11 Ford Focus SE
90 day: 36.78 mpg (US)
Thanks: 1
Thanked 51 Times in 38 Posts
Quote:
Originally Posted by Occasionally6 View Post
Causing the backfire was sport in my (misspent) youth. Some of the responses of bystanders were amusing until I considered that, given returned vets and gun massacres, they could have been genuinely in fear for their lives.
When I was in college, someone was driving an old truck through the campus and let off the gas to slow down to let people cross. When the driver got back on the gas it backfired 4 or 5 times.

Probably 10 kids dropped to the ground.

  Reply With Quote
Reply  Post New Thread






Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com