BG Road Demon 625 CFM

[Nick_nl]

Hi Guys,

I was offered a used BG Road demon 625CFM.
The offered one does need a lot of work, the zinc is really weathered and the special fuel line is completely missing.
This has downlegs in the primary side and massive straight boosters in the secondary side combined with 1.69 throttle blades.
Does anyone have experience with this specific version, its not the modern thermoquad clone, but a 4150 vac secondary.
Large images below.
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Would this be a good upgrade to the current holley 1850?

Thanks,

Nick

[RFSPHPbb]

What is the reason for calling it an upgrade? might be a side-grade.

[Nick_nl]

Well the secondary metering block would be nice. Also the secondary boosters look like they are annular, so that might be nice.
And I like the look of a Demon carb

[GTO Geoff]

Use a Edelbrock 650 AVS & never look back...It has annular boosters in the primaries, where it is important....

[Nick_nl]

You really seem to like the edelbrock products. I have been testing a edelbrock 1406, but I wasn't able to get it to run right all the time. I've spent a fortune on needles and jets, still it was only ok, not great.
The current 1850 is much snappier.
Also I have been testing a Demon with 4 annular boosters, this wasn't great either.

[jmarkaudio]

GTO Geoff before I would use an Edelbrock I would use a Quadrajet... The Holley design is so easy to modify and tune compare to the Edelbrock is why a lot use them. And annulars can be added to most Holleys.