Well i have successfully transformed my 68 I6 into a V8. It was heck of a job but it was well worth it. The only thing I suggest is to have a v8 parts car. Its pretty much nuts, bolts, and lots of time if your doing it alone, which was my situation.

Anyways my actual question goes as follows. I now have a 351W. with a Holley 4V and and 4V offenhauser intake. Im not sure if there were ever any internals done to the engine. The 4 barrels do not work on the Carb. Also the choke is all screwy. So rather than attempt to rebuild it going to replace. What is the cfm rating I should be looking for optimal performance ?
Thanks

 

Congradulations!!

and I say go with a 600cfm, vac secondary.

 

Yep, for a stock 351 w/mild upgrades I'd do the 600 also.
[align=left] [/align]

 

Stock would be a 480 cfm carb.