new headers......
2dooreighty5
08-21-2009, 02:33 AM
i just got those headers on and the car is sounding great once i give it some gas but when its at idle its running rough.... timing is on but the motor is shaking alot..... my fring said it was because there was so much air leaving the motor... its a stock intake and carb on a 305.... should i replace the intake....
silicon212
08-21-2009, 12:22 PM
i just got those headers on and the car is sounding great once i give it some gas but when its at idle its running rough.... timing is on but the motor is shaking alot..... my fring said it was because there was so much air leaving the motor... its a stock intake and carb on a 305.... should i replace the intake....
You will have to rejet the carb. The headers will require a richer mixture. If you have access to a dwell meter and spend a little time researching something I've written here on how to adjust the M/C-IAB circuits, you can adjust the idle air bleed to richen it up a little in the idle circuit - don't mess with the idle mixture screws. Keep in mind this only affects idle and off-idle (low speed cruising etc), so you will still need to rejet.
You will have to rejet the carb. The headers will require a richer mixture. If you have access to a dwell meter and spend a little time researching something I've written here on how to adjust the M/C-IAB circuits, you can adjust the idle air bleed to richen it up a little in the idle circuit - don't mess with the idle mixture screws. Keep in mind this only affects idle and off-idle (low speed cruising etc), so you will still need to rejet.
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