Tempest 455
Well-Known Member
Finally got a chance to work the bugs out of my carb on the Roadrunner I bought. Car is very nice and original but at some point, a Holley Street Avenger 670 was installed. No offense to anyone out there, but I hate these carbs. A correct carb will go on this winter. The car had all the typical problems with an out of the box Avenger. Flat spots, surging at idle, did not pull very well, exhaust burned eyes at idle, stumble when going around corners etc.
I have played w/ these enough to know the issues with them. Took the carb apart Sat morning and made some changes, which are as follows:
*Float level set correctly. Was way low on primary and sec.
*PV changed.
*Squirter size increased. Don't know where Holley is having these made now (China?) but there is no way the squirter marked #31 was a #31. I have a box of these and looked at them under magnification and again, it's marked wrong.
*Jetted up from 65 to 70 on primary.
*Changed secondary spring from black to yellow.
*Adjusted secondary idle speed on carb. This helps so primary is not too high and past transition.
*Re-set timing.
*Re-set idle mixture after all this.
My son and I took car for a drive. No flat spots, surging, burning eyes (from lean missfire) no stumbles etc. Car ran great and pulls very hard for a 3.23 geared 383. In fact I want to say it feels quicker than a much larger displacement stock Musclecar from another make I had years ago.
Sorry no burnout, but we did a blast up to 75 MPH. Will try and get a burnout next time. Just wanted to see how it ran w/ the changes.
[video=youtube;L2LQCR6tzrU]http://www.youtube.com/watch?v=L2LQCR6tzrU[/video]
I have played w/ these enough to know the issues with them. Took the carb apart Sat morning and made some changes, which are as follows:
*Float level set correctly. Was way low on primary and sec.
*PV changed.
*Squirter size increased. Don't know where Holley is having these made now (China?) but there is no way the squirter marked #31 was a #31. I have a box of these and looked at them under magnification and again, it's marked wrong.
*Jetted up from 65 to 70 on primary.
*Changed secondary spring from black to yellow.
*Adjusted secondary idle speed on carb. This helps so primary is not too high and past transition.
*Re-set timing.
*Re-set idle mixture after all this.
My son and I took car for a drive. No flat spots, surging, burning eyes (from lean missfire) no stumbles etc. Car ran great and pulls very hard for a 3.23 geared 383. In fact I want to say it feels quicker than a much larger displacement stock Musclecar from another make I had years ago.
Sorry no burnout, but we did a blast up to 75 MPH. Will try and get a burnout next time. Just wanted to see how it ran w/ the changes.
[video=youtube;L2LQCR6tzrU]http://www.youtube.com/watch?v=L2LQCR6tzrU[/video]
