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From: At my Bar drinking and wrenching in Lafayette Colorado
...or simply check the number cast into the carb in the location I stated. It identifies the carb just like Holley does with list numbers. From that, you can get every spec on the carb - much more detailed than the Holley list number spec sheet.
From: At my Bar drinking and wrenching in Lafayette Colorado
Boomer880 -
Are you going to check and post the number so I can tell you what your carb is..? Or were you simply checking to see if I had the expertise to ID the carb? The answer is, "yes."
From: At my Bar drinking and wrenching in Lafayette Colorado
Yup. Here is the Barry Grant Demon ID number on a carb I have in the shop right now:
Your #6 ID identifies the carb as follows:
Barry Grant Speed Demon 650 cfm, downleg booster
Part number: 1282010
Venturi size: 1.280
Idle Air Bleeds, Primary: .070
Idle Air Bleeds, Secondary: .063
High Speed Air Bleeds: .041
Booster leg: .140
Squirter size: 31
Butterfly size: 1-11/16
Pump Cam: #330 Pink
Primary Metering Block: A-12400
Secondary Metering Block: A-12401
Siphon Break: .028
E-Holes, all 3 positions: .031
PVCR size: .059
IFR: .033
Main Jets, Primary: 70
Main Jets, Secondary: 78
Power Valve: 6.5
That's what your "#6" ID code tells you.
Here is an ad for that carb back when they were still being sold - it gives you some general overview of how the carb was described when it was being sold. This ad describes the vacuum secondary version of your mechanical secondary carb, but the photo is of the mechanical carb:
From: At my Bar drinking and wrenching in Lafayette Colorado
As additional information, the # "6" carbs came with either annular or downleg boosters, which changes the cfm rating of the carb. The downleg booster carbs are 650 cfm, and the annular carbs are 575 cfm. Boomer880's carb has downleg boosters, so it's 650 cfm as outlined in my post above. The annular boosters look like this:
Note that someone has done some "rebuilding" work on Boomer's carb: They have installed Holley needle/seat assemblies with Holley adjusting hardware. The Demon carb kits come with the real Demon adjusters which look like the hardware shown on the carb above. If they screwed around with the hardware and installed the wrong parts, chances are good that other things on the carb have been messed with as well. For example, if they used a Holley throttle plate gasket, there are 2 holes that are in the wrong place for a Demon carb, and the carb will have idle issues. I'd tear that carb down and check every spec on it...
Lars
The guy building this car passed away at age 38 and it sat for some time. The engine is a crate 454, and the family said it was taken out to a 548ci. Not sure what I all have here, but I will work through it strategically. My hope is to have her starting in spring. It has a built 700-4R trans and a new rear. Car looks to be no-hit with a solid frame and birdcage. Should be interesting.
From: At my Bar drinking and wrenching in Lafayette Colorado
I'd sell that little 650 carb if I were you and use an 850 on that engine. The 650 would be good for a 302... The 750 Demon I show in my ID# photos above is going on a 350 in a Camaro, and it's just the right size.
Lars
From: At my Bar drinking and wrenching in Lafayette Colorado
Boomer -
The carb you have shown in your photos is one of the Speed Demon carbs built back when Barry Grant was still running the company. In spite of quality control problems with the Demon carbs at that time, once the carbs are properly set up, they are excellent carbs for a high performance street engine. They are desireable carbs by people who know what they are. That carb on a 4-speed 327 Vette or Camaro would be kick-***. Don't give it away for nothing...
Lars
