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Steve@Rennsport
Steve@Rennsport is offline
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Join Date: Jul 2001
Location: Portland Oregon
Posts: 7,007
Quote:
Originally Posted by Turbo Den View Post
1) cold temp is 2-4 C/ 36-39 F'
2) assuming my summer mixture is perfect, i assume cold weather makes the engine run lean. am I correct?
3) it will not go past 4k rpm. as i step WOT, rev builds slowly to 3500-4000rpm and stop going up.
As John suggested, carburetor icing is quite normal on these cars when operated in cold, moist weather. Its exacerbated by the lack of intake air pre-heat and cold manifolds (needed for summer operation). When the carbs do ice up, the main venturi becomes obstructed with ice that can severely restrict engine RPM.

Once its melted by engine heat, normal operation is resumed, BUT,....BUT if the intaker manifolds and carbs remain cold, the ice won't melt. I would suggest removing any insulators between the heads and manifolds, if they are present for a start.

Indeed, cold weather makes the car go leaner so a review of the jetting is in order.
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Steve Weiner
Rennsport Systems
Portland Oregon
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Old 12-08-2007, 04:57 PM
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