The Holley #8007, 390 cfm 4 barrel is a member of the 4160 family, and was designed for street applications. [Although the fine print says it's only legal for off-road use in the state of california...] I used one on my 292 in a '68 C/10 for about 24 years. Stock build, only .030 over. After another rebuild in '02, we couldn't get the carb to seal. Rather than try to plane the base or graft on a new base plate, I decided to get an Edelbrock 1404 500 cfm and get a carb I could tune myself without adult supervision.
On the whole the 390 cfm p/n 8007 was a good carb for a stock or mildly built L6 with headers and aftermarket intake. It was even more fun when I put the 50cc accelerator pump on it.
Holley also makes a 4150,[p/n ..?] 390 cfm 4 barrel for the circle track crowd, perhaps this is the source of the confusion.
I/I #4101
'71 GMC Jimmy 350, sm465, np205,3.73 posi.
'68 C/10 Stepside 292 (.030 over) Offy Intake, 500 CFM AFB,Clif headers, sm465, 3.73 posi.
'67 K/10 454 project.
'72 K/5 rolling frame project.
| 
