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Old 04-24-2009, 11:09 AM
kobrabytes kobrabytes is offline
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Cobra Make, Engine: KMP532, KC427FE, TWM
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Quote:
Originally Posted by fkemmerer View Post
Len,

Hi. I am on this forum as Rick indicated in his post. I'm curious why you went to alpha-N vs. sticking with speed-density and solving your problems another way. Alpha-N is great on the drag strip where you run the motor at 2 setting - idle and WOT but its usually not the best choice (or necessary) for the street.

- Fred
HI Fred,

In speed density the map sensor doesn't deal well with the low vacuum that I get off the TWM set up, around 6lbs at idle. The idle in SD mode was very eradic, the cursor never sat in a single cell. We even tried buffering the vacuum to no avail. Even with the throttle fully closed the computer would tell me that I was at 60% and always dump in fuel, lots of back fire on deceleration. Plugs continuously fouled. Here in SLC we are at a base altitude of 4500ft, I do drives up to and over 10k ft. Each trip was a guarantee to Checker that I'd be by for new plugs.

FAST says not to use speed density with less than 10 lbs of vacuum.

Currently I have the car running much better in Alpha N than it ever did in SD mode. No backfire and the idle is rock solid. Plugs stopped fouling.

I don't understand what you mean about two step? Idle is tuned really nicely on the first row. I have 15 other rows to define cruse and power...
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