1972 400

[66 convert]

1972 400 mopar purple shaft cam (size unsure)
1970 440 heads edelbrock performer intake new street demon 625 cfm carb.Car only 6to7hg vacuum at idle runs good till driven for 30 to 40 minutes then idle drops off and wants to stall but will start right back up just can't get it right any suggestions?

 

[mopar367]

Is the carb tuned properly? Use a vauccum gauge and adjust your timing and idle screws on carb to where the gauge produces the most vacuum.

 

[66 convert]

Will try again waiting for carb calibration kit going to try lighter metering rod springs do to the low vacuum at idle . thanks for the reply