AFR Safety & Spinning Tires

Testing and development of Megasquirt 3

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shaodome
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AFR Safety & Spinning Tires

Post by shaodome »

So while road tuning the other day an interesting problem came up. In 1st or 2nd gear the car makes enough power to roast the tires if the driver isn't careful or the road conditions are not perfect. As a result, the engine unloads, cylinder pressure drops and the AFR reads a little on the lean side. This ultimately triggers the AFR safety system.

In a racing situation, the tires spinning would eventually grab when the car's actual MPH catches up, or at least enough to throw the next gear. Right now the AFR system triggers and makes that not possible. The short term solution would be to add a minimum gear for the AFR Safety setup, but I'm curious to know what other's thoughts are on the matter.
jsmcortina
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Re: AFR Safety & Spinning Tires

Post by jsmcortina »

Don't you pedal it?

But also....
:msq:

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

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shaodome
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Re: AFR Safety & Spinning Tires

Post by shaodome »

Lol. Fair enough James.

I'm on my way to New York to do some tuning. I'll get the logs posted on Friday evening when I get back.
shaodome
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Re: AFR Safety & Spinning Tires

Post by shaodome »

This also makes me think of something else.....

With traction control activated and if spark is being cut, that too would Read as a false lean condition and activate the AFR safety, no?
jsmcortina
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Re: AFR Safety & Spinning Tires

Post by jsmcortina »

shaodome wrote:This also makes me think of something else.....

With traction control activated and if spark is being cut, that too would Read as a false lean condition and activate the AFR safety, no?
Possibly and worth investigating.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
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