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Re: piggy back chips??

Posted: September 2nd, 2008, 10:09 am
by wytbishop
Nd4SpdSe wrote:
wytbishop wrote:This will probably improve the car's performance at RPM's where the mixture is lean, but at RPM's where the mixture is already good, or a little rich, it can really mess up performance and will destroy your fuel economy overall.
No man, lean is better for performance
Allow me to clarify my position...when I say lean I mean to say "too lean". Just as when I say rich I mean "too rich". Optimal AFR is neither lean nor rich it is ...optimal. Factory fuel maps are typically on the lean side, particularly at idle. These spots in the range which are too lean will see an improvement in performance when a "Chip" is used. Spots in the map which are close to optimal or slightly rich will be made worse.

Re: piggy back chips??

Posted: September 2nd, 2008, 11:26 am
by Nd4SpdSe
wytbishop wrote:
Nd4SpdSe wrote:
wytbishop wrote:This will probably improve the car's performance at RPM's where the mixture is lean, but at RPM's where the mixture is already good, or a little rich, it can really mess up performance and will destroy your fuel economy overall.
No man, lean is better for performance
Allow me to clarify my position...when I say lean I mean to say "too lean". Just as when I say rich I mean "too rich". Optimal AFR is neither lean nor rich it is ...optimal. Factory fuel maps are typically on the lean side, particularly at idle. These spots in the range which are too lean will see an improvement in performance when a "Chip" is used. Spots in the map which are close to optimal or slightly rich will be made worse.
You sure? As far as I know cars from the factory run more towards rich. Running towards lean is risky since that can cause damage if it goes too low, even for a second. You will not see an improvement if you add more fuel when it's running lean, that will actually make it lose power. There are ideal ratios to run, those depends if your N/A or FI, but typically you want to run as lean as you can. Too lean and you either Ping or even worse, Detonate

Re: piggy back chips??

Posted: September 2nd, 2008, 2:26 pm
by wytbishop
I'm going by the experience I had and the information I gleaned while tuning my bike with the Power Commander. My bike's stock fuel map was slightly lean most of the way up the range, but quite lean at idle. It was richest at the point of peak HP. I was told by the tuner that this was generally the case.

On this I am certainly no expert.