Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

Idle and Perf Issues

<< < (2/5) > >>

77cruiser:
Just for yucks try about 20 initial.

RMA:
I did try up to about 16 degrees, (eyeball it Pointer stops at 14).  Idle got worse.  I could try again with a dial back light.

Cliff Ruggles:
Your main problem is the cam selection.  Not enough compression for that much duration even in the big 455 engine.

It's going to want a LOT of idle fuel, bypass air and initial timing to be happy. 

The exact same engine build at 10.5 to 1 compression would be making a LOT more vacuum and pretty happy with that cam, but even then it wouldn't be making a lot of vacuum at idle speed and still require some help from the carbs idle system to be ideal......

RMA:
Thank you for the feedback.  Any suggestions  on initial timing?   Also, any ideas why the secondaries will not kick in?  I have full travel on the throttle linkage.  Thanks

RMA:
Bumped the initial timing to 20 she seems happier.  Mixture screws out about 6 turns in park Idle is 750 and drive around 600 which is an improvement.  Check on vacuum tomorrow.  Hoping for better weather and take a drive.   I appreciate all the feedback!  Thank you.

Navigation

[0] Message Index

[#] Next page

[*] Previous page

Go to full version