what is happening when running lean (not a noob question)
02-24-2008, 06:18 PM
#11
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Join Date: Jul 2003
Posts: 6,449
Re: what is happening when running lean (not a noob question)
Originally Posted by t_cel_t
well its just that ive seen what happens to pistons when a motor goes lean and it like a hole is burned right through it. the hole is smooth almost like it is gradual.
but then ive seen pistons that were like totally cracked to hell with bent rods.
i just thought something else was happening
but then ive seen pistons that were like totally cracked to hell with bent rods.
i just thought something else was happening
02-25-2008, 04:45 PM
#14
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Join Date: Jun 2006
Posts: 1,618
Re: what is happening when running lean (not a noob question)
Originally Posted by brettsb16a2
A lean mixture can also just cause a misfire and no detonation in vacuum with a light load or no load
because i had to do that for a speed trap and i thought my ---- was going to blow.
full vacuum but like 21 afr.
02-25-2008, 07:19 PM
#15
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Location: NE-PA
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Re: what is happening when running lean (not a noob question)
Originally Posted by the 13th round
would this be what is happening when you are hauling *** then let off the gas?
because i had to do that for a speed trap and i thought my ---- was going to blow.
full vacuum but like 21 afr.
because i had to do that for a speed trap and i thought my ---- was going to blow.
full vacuum but like 21 afr.
02-26-2008, 01:18 AM
#16
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Join Date: May 2005
Posts: 0
Re: what is happening when running lean (not a noob question)
Originally Posted by 89shithatch
wrong mixture of air and fuel caused premature combustion. which is detonation. too much air and not nough fuel.
Pre-Ignition is NOT detonation. They are two entirely different phenomena.
Detonation is a second ignition after the spark plug has already initiated combustion.
Pre-Ignition is ignition before the spark plug has a chance to do it, which is WAY WAY more harmful than detonation. Pre-Ignition is a combustion event that totally works against piston travel, kind of like the worst case of advanced timing. It happens because when the piston is at BDC, the pressure in the cylinder is very low, thus any fuel inside is really easy to ignite, but has a slow flame propagation. Any hotspots in the cylinder could ignite the mixture.
02-26-2008, 10:42 PM
#18
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Join Date: Sep 2004
Posts: 1,588
Re: what is happening when running lean (not a noob question)
Originally Posted by the 13th round
that bad?
it's normal.
02-27-2008, 05:17 AM
#19
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Join Date: May 2005
Posts: 0
Re: what is happening when running lean (not a noob question)
Originally Posted by the 13th round
that bad?
No, think about it.
You need fuel to have any form of combustion. Without fuel, you can't have normal combustion, detonation, or pre-ignition.
Fuel cut is a rather harsh way to cut engine speed though. Ignition cut is way way softer.
