ConcoursMustang Forums

Restoring - General discussions that span across many different groups of years and models => Drivetrain => Topic started by: AJ on January 14, 2025, 09:52:14 AM

Title: Old style Holley needle seat
Post by: AJ on January 14, 2025, 09:52:14 AM

Not sure Old Style is the appropriate terminology.  Did any 69 or 70 Holley 780 or 735 carbs come from factory with these

Title: Re: Old style Holley needle seat
Post by: Bob Gaines on January 14, 2025, 12:30:16 PM

No

Title: Re: Old style Holley needle seat
Post by: J_Speegle on January 14, 2025, 05:14:18 PM

Original style

(https://www.concoursmustang.com/forum/gallery/20/6-140125161351-208641253.jpeg)

Title: Re: Old style Holley needle seat
Post by: Bob Gaines on January 14, 2025, 05:18:43 PM

The needle seat adjuster was typically a silver nut and a silver set screw originally. Some restorers mistakenly make the set screw zinc gold.

Title: Re: Old style Holley needle seat
Post by: Dan Case on January 15, 2025, 08:34:53 AM

Looks like the aftermarket brass jam nut included in Borg-Warner brand rebuild kits. That means the valve was probably a Borg-Warner version item also.

My experience with the Borg-Warner kits is all bad. I never used one but I repaired Shelby and Boss Mustang carburetors somebody else put their kits in. The needle and seat threads were normally a little smaller than required to have a good fit. Users sometimes had slow fuel leaks at the jam nut and sometimes in efforts to stop the leakage somebody kept tightening the nut and ended up ripping some to a lot of the threads out of the fuel bowl.