I think two 650 double pumpers would definitely be too much for most SBC engines, unless the engine was a large cubic inch engine, with a lot of HP. But twin 600cfm 1850's with vacuum secondaries wont be too much at all. I think for most people's tunnel ram equipped cars that see mostly street use, the 600cfm 1850's are the best choice whether it's a well built SBC, or BBC. On my BBC in my Falcon they worked great once I changed the jetting large enough to get them richened up. I went from the stock 64 jets to 78 jets, and not only did it make huge HP change, but the engine ran 20 degrees cooler! It was that lean with the stock jets! And at the strip it would lift the front wheels at launch after I upsized the jets. Before I upsized the engine would surge if I was cruising at a steady speed like a blower motor. It was gasping for more fuel, and I didn't know it. A buddy asked what jets I was running, and was very shocked when he heard they were stock. It also ran pretty warm, so a big win going to larger jets.
My buddy's 32 ford 406 SBC with a 8 71 blower on it has 2 80592 blower carbs on it ,runs great 4:10 rear gear Tk 500 5 speed gets in the 20 mpg on the freeway
Most here might know this already. If you use a flexible fuel line, makes it so much easier to access jets.
I have a set of quick jet change fuel bowls by Holley.... Those are pretty handy items to have during tuning sessions at the drags....
This ? https://www.holley.com/products/fuel_systems/carburetor_components/parts/34-25 Didn’t know Thanks
That be them.... I have the complete set of 3.... 2 for double pumpers and one for the rear on a vacuum secondary carb.... Check those out on Summit auto parts....
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